Graft pcb-tools-extension master onto gerbonara main

11 files changed, 2964 insertions, 0 deletions

diff --git a/gerberex/__init__.py b/gerberex/__init__.py
new file mode 100644
index 0000000..f379c1c
--- /dev/null
+++ b/gerberex/__init__.py
@@ -0,0 +1,15 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+"""
+Gerber Tools Extension
+======================
+**Gerber Tools Extenstion**
+gerber-tools-extension is a extention package for gerber-tools.
+This package provide panelizing of PCB fucntion.
+"""
+
+from gerberex.common import read, loads, rectangle
+from gerberex.composition import GerberComposition, DrillComposition
+from gerberex.dxf import DxfFile
diff --git a/gerberex/am_expression.py b/gerberex/am_expression.py
new file mode 100644
index 0000000..f43ba2e
--- /dev/null
+++ b/gerberex/am_expression.py
@@ -0,0 +1,184 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+from gerber.utils import *
+from gerber.am_eval import OpCode
+from gerber.am_statements import *
+
+class AMExpression(object):
+    CONSTANT = 1
+    VARIABLE = 2
+    OPERATOR = 3
+
+    def __init__(self, kind):
+        self.kind = kind
+
+    @property
+    def value(self):
+        return self
+
+    def optimize(self):
+        pass
+    
+    def to_inch(self):
+        return AMOperatorExpression(AMOperatorExpression.DIV, self, 
+                                    AMConstantExpression(MILLIMETERS_PER_INCH))
+
+    def to_metric(self):
+        return AMOperatorExpression(AMOperatorExpression.MUL, self,
+                                    AMConstantExpression(MILLIMETERS_PER_INCH))
+
+    def to_gerber(self, settings=None):
+        pass
+
+    def to_instructions(self):
+        pass
+    
+class AMConstantExpression(AMExpression):
+    def __init__(self, value):
+        super(AMConstantExpression, self).__init__(AMExpression.CONSTANT)
+        self._value = value
+
+    @property
+    def value(self):
+        return self._value
+
+    def optimize(self):
+        return self
+    
+    def to_gerber(self, settings=None):
+        if isinstance(self._value, str):
+            return self._value
+        gerber = '%.6g' % self._value
+        return '%.6f' % self._value if 'e' in gerber else gerber
+
+    def to_instructions(self):
+        return [(OpCode.PUSH, self._value)]
+    
+class AMVariableExpression(AMExpression):
+    def __init__(self, number):
+        super(AMVariableExpression, self).__init__(AMExpression.VARIABLE)
+        self.number = number
+
+    def optimize(self):
+        return self
+    
+    def to_gerber(self, settings=None):
+        return '$%d' % self.number
+    
+    def to_instructions(self):
+        return (OpCode.LOAD, self.number)
+
+class AMOperatorExpression(AMExpression):
+    ADD = '+'
+    SUB = '-'
+    MUL = 'X'
+    DIV = '/'
+
+    def __init__(self, op, lvalue, rvalue):
+        super(AMOperatorExpression, self).__init__(AMExpression.OPERATOR)
+        self.op = op
+        self.lvalue = lvalue
+        self.rvalue = rvalue
+    
+    def optimize(self):
+        self.lvalue = self.lvalue.optimize()
+        self.rvalue = self.rvalue.optimize()
+
+        if isinstance(self.lvalue, AMConstantExpression) and isinstance(self.rvalue, AMConstantExpression):
+            lvalue = float(self.lvalue.value)
+            rvalue = float(self.rvalue.value)
+            value = lvalue + rvalue if self.op == self.ADD else \
+                lvalue - rvalue if self.op == self.SUB else \
+                lvalue * rvalue if self.op == self.MUL else \
+                lvalue / rvalue if self.op == self.DIV else None
+            return AMConstantExpression(value)
+        elif self.op == self.ADD:
+            if self.rvalue.value == 0:
+                return self.lvalue
+            elif self.lvalue.value == 0:
+                return self.rvalue
+        elif self.op == self.SUB:
+            if self.rvalue.value == 0:
+                return self.lvalue
+            elif self.lvalue.value == 0 and isinstance(self.rvalue, AMConstantExpression):
+                return AMConstantExpression(-self.rvalue.value)
+        elif self.op == self.MUL:
+            if self.rvalue.value == 1:
+                return self.lvalue
+            elif self.lvalue.value == 1:
+                return self.rvalue
+            elif self.lvalue == 0 or self.rvalue == 0:
+                return AMConstantExpression(0)
+        elif self.op == self.DIV:
+            if self.rvalue.value == 1:
+                return self.lvalue
+            elif self.lvalue.value == 0:
+                return AMConstantExpression(0)
+        
+        return self
+        
+    def to_gerber(self, settings=None):
+        return '(%s)%s(%s)' % (self.lvalue.to_gerber(settings), self.op, self.rvalue.to_gerber(settings))
+
+    def to_instructions(self):
+        for i in self.lvalue.to_instructions():
+            yield i
+        for i in self.rvalue.to_instructions():
+            yield i
+        op = OpCode.ADD if self.op == self.ADD else\
+             OpCode.SUB if self.op == self.SUB else\
+             OpCode.MUL if self.op == self.MUL else\
+             OpCode.DIV
+        yield (op, None)
+
+def eval_macro(instructions):
+    stack = []
+
+    def pop():
+        return stack.pop()
+
+    def push(op):
+        stack.append(op)
+
+    def top():
+        return stack[-1]
+
+    def empty():
+        return len(stack) == 0
+
+    for opcode, argument in instructions:
+        if opcode == OpCode.PUSH:
+            push(AMConstantExpression(argument))
+
+        elif opcode == OpCode.LOAD:
+            push(AMVariableExpression(argument))
+
+        elif opcode == OpCode.STORE:
+            yield (-argument, [pop()])
+
+        elif opcode == OpCode.ADD:
+            op1 = pop()
+            op2 = pop()
+            push(AMOperatorExpression(AMOperatorExpression.ADD, op2, op1))
+
+        elif opcode == OpCode.SUB:
+            op1 = pop()
+            op2 = pop()
+            push(AMOperatorExpression(AMOperatorExpression.SUB, op2, op1))
+
+        elif opcode == OpCode.MUL:
+            op1 = pop()
+            op2 = pop()
+            push(AMOperatorExpression(AMOperatorExpression.MUL, op2, op1))
+
+        elif opcode == OpCode.DIV:
+            op1 = pop()
+            op2 = pop()
+            push(AMOperatorExpression(AMOperatorExpression.DIV, op2, op1))
+
+        elif opcode == OpCode.PRIM:
+            yield (argument, stack)
+            stack = []
diff --git a/gerberex/am_primitive.py b/gerberex/am_primitive.py
new file mode 100644
index 0000000..a3ad824
--- /dev/null
+++ b/gerberex/am_primitive.py
@@ -0,0 +1,448 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+from gerber.utils import *
+from gerber.am_statements import *
+from gerber.am_eval import OpCode
+
+from gerberex.am_expression import eval_macro, AMConstantExpression, AMOperatorExpression
+
+class AMPrimitiveDef(AMPrimitive):
+    def __init__(self, code, exposure=None, rotation=None):
+        super(AMPrimitiveDef, self).__init__(code, exposure)
+        if not rotation:
+            rotation = AMConstantExpression(0)
+        self.rotation = rotation
+
+    def rotate(self, angle, center=None):
+        self.rotation = AMOperatorExpression(AMOperatorExpression.ADD, 
+                                             self.rotation, 
+                                             AMConstantExpression(float(angle)))
+        self.rotation = self.rotation.optimize()
+
+    def to_inch(self):
+        pass
+    
+    def to_metric(self):
+        pass
+
+    def to_gerber(self, settings=None):
+        pass
+
+    def to_instructions(self):
+        pass
+
+class AMCommentPrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        return cls(code, modifiers[0])
+    
+    def __init__(self, code, comment):
+        super(AMCommentPrimitiveDef, self).__init__(code)
+        self.comment = comment
+    
+    def to_gerber(self, settings=None):
+        return '%d %s*' % (self.code, self.comment.to_gerber())
+    
+    def to_instructions(self):
+        return [(OpCode.PUSH, self.comment), (OpCode.PRIM, self.code)]
+
+class AMCirclePrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        exposure = 'on' if modifiers[0].value == 1 else 'off'
+        diameter = modifiers[1]
+        center_x = modifiers[2]
+        center_y = modifiers[3]
+        rotation = modifiers[4] if len(modifiers)>4 else AMConstantExpression(float(0))
+        return cls(code, exposure, diameter, center_x, center_y, rotation)
+
+    def __init__(self, code, exposure, diameter, center_x, center_y, rotation):
+        super(AMCirclePrimitiveDef, self).__init__(code, exposure, rotation)
+        self.diameter = diameter
+        self.center_x = center_x
+        self.center_y = center_y
+
+    def to_inch(self):
+        self.diameter = self.diameter.to_inch().optimize()
+        self.center_x = self.center_x.to_inch().optimize()
+        self.center_y = self.center_y.to_inch().optimize()
+    
+    def to_metric(self):
+        self.diameter = self.diameter.to_metric().optimize()
+        self.center_x = self.center_x.to_metric().optimize()
+        self.center_y = self.center_y.to_metric().optimize()
+
+    def to_gerber(self, settings=None):
+        data = dict(code = self.code,
+                    exposure = 1 if self.exposure == 'on' else 0,
+                    diameter = self.diameter.to_gerber(settings),
+                    x = self.center_x.to_gerber(settings),
+                    y = self.center_y.to_gerber(settings),
+                    rotation = self.rotation.to_gerber(settings))
+        return '{code},{exposure},{diameter},{x},{y},{rotation}*'.format(**data)
+        
+    def to_instructions(self):
+        yield (OpCode.PUSH, 1 if self.exposure == 'on' else 0)
+        for modifier in [self.diameter, self.center_x, self.center_y, self.rotation]:
+            for i in modifier.to_instructions():
+                yield i
+        yield (OpCode.PRIM, self.code)
+
+class AMVectorLinePrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        code = code
+        exposure = 'on' if modifiers[0].value == 1 else 'off'
+        width = modifiers[1]
+        start_x = modifiers[2]
+        start_y = modifiers[3]
+        end_x = modifiers[4]
+        end_y = modifiers[5]
+        rotation = modifiers[6]
+        return cls(code, exposure, width, start_x, start_y, end_x, end_y, rotation)
+
+    def __init__(self, code, exposure, width, start_x, start_y, end_x, end_y, rotation):
+        super(AMVectorLinePrimitiveDef, self).__init__(code, exposure, rotation)
+        self.width = width
+        self.start_x = start_x
+        self.start_y = start_y
+        self.end_x = end_x
+        self.end_y = end_y
+
+    def to_inch(self):
+        self.width = self.width.to_inch().optimize()
+        self.start_x = self.start_x.to_inch().optimize()
+        self.start_y = self.start_y.to_inch().optimize()
+        self.end_x = self.end_x.to_inch().optimize()
+        self.end_y = self.end_y.to_inch().optimize()
+    
+    def to_metric(self):
+        self.width = self.width.to_metric().optimize()
+        self.start_x = self.start_x.to_metric().optimize()
+        self.start_y = self.start_y.to_metric().optimize()
+        self.end_x = self.end_x.to_metric().optimize()
+        self.end_y = self.end_y.to_metric().optimize()
+
+    def to_gerber(self, settings=None):
+        data = dict(code = self.code,
+                    exposure = 1 if self.exposure == 'on' else 0,
+                    width = self.width.to_gerber(settings),
+                    start_x = self.start_x.to_gerber(settings),
+                    start_y = self.start_y.to_gerber(settings),
+                    end_x = self.end_x.to_gerber(settings),
+                    end_y = self.end_y.to_gerber(settings),
+                    rotation = self.rotation.to_gerber(settings))
+        return '{code},{exposure},{width},{start_x},{start_y},{end_x},{end_y},{rotation}*'.format(**data)
+        
+    def to_instructions(self):
+        yield (OpCode.PUSH, 1 if self.exposure == 'on' else 0)
+        modifiers = [self.width, self.start_x, self.start_y, self.end_x, self.end_y, self.rotation]
+        for modifier in modifiers:
+            for i in modifier.to_instructions():
+                yield i
+        yield (OpCode.PRIM, self.code)
+
+class AMCenterLinePrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        code = code
+        exposure = 'on' if modifiers[0].value == 1 else 'off'
+        width = modifiers[1]
+        height = modifiers[2]
+        x = modifiers[3]
+        y = modifiers[4]
+        rotation = modifiers[5]
+        return cls(code, exposure, width, height, x, y, rotation)
+
+    def __init__(self, code, exposure, width, height, x, y, rotation):
+        super(AMCenterLinePrimitiveDef, self).__init__(code, exposure, rotation)
+        self.width = width
+        self.height = height
+        self.x = x
+        self.y = y
+
+    def to_inch(self):
+        self.width = self.width.to_inch().optimize()
+        self.height = self.height.to_inch().optimize()
+        self.x = self.x.to_inch().optimize()
+        self.y = self.y.to_inch().optimize()
+    
+    def to_metric(self):
+        self.width = self.width.to_metric().optimize()
+        self.height = self.height.to_metric().optimize()
+        self.x = self.x.to_metric().optimize()
+        self.y = self.y.to_metric().optimize()
+
+    def to_gerber(self, settings=None):
+        data = dict(code = self.code,
+                    exposure = 1 if self.exposure == 'on' else 0,
+                    width = self.width.to_gerber(settings),
+                    height = self.height.to_gerber(settings),
+                    x = self.x.to_gerber(settings),
+                    y = self.y.to_gerber(settings),
+                    rotation = self.rotation.to_gerber(settings))
+        return '{code},{exposure},{width},{height},{x},{y},{rotation}*'.format(**data)
+        
+    def to_instructions(self):
+        yield (OpCode.PUSH, 1 if self.exposure == 'on' else 0)
+        modifiers = [self.width, self.height, self.x, self.y, self.rotation]
+        for modifier in modifiers:
+            for i in modifier.to_instructions():
+                yield i
+        yield (OpCode.PRIM, self.code)
+
+class AMOutlinePrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        num_points = int(modifiers[1].value + 1)
+        code = code
+        exposure = 'on' if modifiers[0].value == 1 else 'off'
+        addrs = modifiers[2:num_points * 2 + 2]
+        rotation = modifiers[2 + num_points * 2]
+        return cls(code, exposure, addrs, rotation)
+
+    def __init__(self, code, exposure, addrs, rotation):
+        super(AMOutlinePrimitiveDef, self).__init__(code, exposure, rotation)
+        self.addrs = addrs
+
+    def to_inch(self):
+        self.addrs = [i.to_inch().optimize() for i in self.addrs]
+    
+    def to_metric(self):
+        self.addrs = [i.to_metric().optimize() for i in self.addrs]
+ 
+    def to_gerber(self, settings=None):
+        def strs():
+            yield '%d,%d,%d' % (self.code, 
+                                1 if self.exposure == 'on' else 0,
+                                len(self.addrs) / 2 - 1)
+            for i in self.addrs:
+                yield i.to_gerber(settings)
+            yield self.rotation.to_gerber(settings)
+
+        return '%s*' % ','.join(strs())
+        
+    def to_instructions(self):
+        yield (OpCode.PUSH, 1 if self.exposure == 'on' else 0)
+        yield (OpCode.PUSH, int(len(self.addrs) / 2 - 1))
+        for modifier in self.addrs:
+            for i in modifier.to_instructions():
+                yield i
+        for i in self.rotation.to_instructions():
+            yield i
+        yield (OpCode.PRIM, self.code)
+
+class AMPolygonPrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        code = code
+        exposure = 'on' if modifiers[0].value == 1 else 'off'
+        vertices = modifiers[1]
+        x = modifiers[2]
+        y = modifiers[3]
+        diameter = modifiers[4]
+        rotation = modifiers[5]
+        return cls(code, exposure, vertices, x, y, diameter, rotation)
+
+    def __init__(self, code, exposure, vertices, x, y, diameter, rotation):
+        super(AMPolygonPrimitiveDef, self).__init__(code, exposure, rotation)
+        self.vertices = vertices
+        self.x = x
+        self.y = y
+        self.diameter = diameter
+
+    def to_inch(self):
+        self.x = self.x.to_inch().optimize()
+        self.y = self.y.to_inch().optimize()
+        self.diameter = self.diameter.to_inch().optimize()
+    
+    def to_metric(self):
+        self.x = self.x.to_metric().optimize()
+        self.y = self.y.to_metric().optimize()
+        self.diameter = self.diameter.to_metric().optimize()
+
+    def to_gerber(self, settings=None):
+        data = dict(code = self.code,
+                    exposure = 1 if self.exposure == 'on' else 0,
+                    vertices = self.vertices.to_gerber(settings),
+                    x = self.x.to_gerber(settings),
+                    y = self.y.to_gerber(settings),
+                    diameter = self.diameter.to_gerber(settings),
+                    rotation = self.rotation.to_gerber(settings))
+        return '{code},{exposure},{vertices},{x},{y},{diameter},{rotation}*'.format(**data)
+        
+    def to_instructions(self):
+        yield (OpCode.PUSH, 1 if self.exposure == 'on' else 0)
+        modifiers = [self.vertices, self.x, self.y, self.diameter, self.rotation]
+        for modifier in modifiers:
+            for i in modifier.to_instructions():
+                yield i
+        yield (OpCode.PRIM, self.code)
+
+class AMMoirePrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        code = code
+        exposure = 'on'
+        x = modifiers[0]
+        y = modifiers[1]
+        diameter = modifiers[2]
+        ring_thickness = modifiers[3]
+        gap = modifiers[4]
+        max_rings = modifiers[5]
+        crosshair_thickness = modifiers[6]
+        crosshair_length = modifiers[7]
+        rotation = modifiers[8]
+        return cls(code, exposure, x, y, diameter, ring_thickness, gap,
+                   max_rings, crosshair_thickness, crosshair_length, rotation)
+
+    def __init__(self, code, exposure, x, y, diameter, ring_thickness, gap, max_rings, crosshair_thickness, crosshair_length, rotation):
+        super(AMMoirePrimitiveDef, self).__init__(code, exposure, rotation)
+        self.x = x
+        self.y = y
+        self.diameter = diameter
+        self.ring_thickness = ring_thickness
+        self.gap = gap
+        self.max_rings = max_rings
+        self.crosshair_thickness = crosshair_thickness
+        self.crosshair_length = crosshair_length
+
+    def to_inch(self):
+        self.x = self.x.to_inch().optimize()
+        self.y = self.y.to_inch().optimize()
+        self.diameter = self.diameter.to_inch().optimize()
+        self.ring_thickness = self.ring_thickness.to_inch().optimize()
+        self.gap = self.gap.to_inch().optimize()
+        self.crosshair_thickness = self.crosshair_thickness.to_inch().optimize()
+        self.crosshair_length = self.crosshair_length.to_inch().optimize()
+    
+    def to_metric(self):
+        self.x = self.x.to_metric().optimize()
+        self.y = self.y.to_metric().optimize()
+        self.diameter = self.diameter.to_metric().optimize()
+        self.ring_thickness = self.ring_thickness.to_metric().optimize()
+        self.gap = self.gap.to_metric().optimize()
+        self.crosshair_thickness = self.crosshair_thickness.to_metric().optimize()
+        self.crosshair_length = self.crosshair_length.to_metric().optimize()
+
+    def to_gerber(self, settings=None):
+        data = dict(code = self.code,
+                    x = self.x.to_gerber(settings),
+                    y = self.y.to_gerber(settings),
+                    diameter = self.diameter.to_gerber(settings),
+                    ring_thickness = self.ring_thickness.to_gerber(settings),
+                    gap = self.gap.to_gerber(settings),
+                    max_rings = self.max_rings.to_gerber(settings),
+                    crosshair_thickness = self.crosshair_thickness.to_gerber(settings),
+                    crosshair_length = self.crosshair_length.to_gerber(settings),
+                    rotation = self.rotation.to_gerber(settings))
+        return '{code},{x},{y},{diameter},{ring_thickness},{gap},{max_rings},'\
+               '{crosshair_thickness},{crosshair_length},{rotation}*'.format(**data)
+        
+    def to_instructions(self):
+        modifiers = [self.x, self.y, self.diameter, 
+                     self.ring_thickness, self.gap, self.max_rings,
+                     self.crosshair_thickness, self.crosshair_length,
+                     self.rotation]
+        for modifier in modifiers:
+            for i in modifier.to_instructions():
+                yield i
+        yield (OpCode.PRIM, self.code)
+
+class AMThermalPrimitiveDef(AMPrimitiveDef):
+    @classmethod
+    def from_modifiers(cls, code, modifiers):
+        code = code
+        exposure = 'on'
+        x = modifiers[0]
+        y = modifiers[1]
+        outer_diameter = modifiers[2]
+        inner_diameter = modifiers[3]
+        gap = modifiers[4]
+        rotation = modifiers[5]
+        return cls(code, exposure, x, y, outer_diameter, inner_diameter, gap, rotation)
+
+    def __init__(self, code, exposure, x, y, outer_diameter, inner_diameter, gap, rotation):
+        super(AMThermalPrimitiveDef, self).__init__(code, exposure, rotation)
+        self.x = x
+        self.y = y
+        self.outer_diameter = outer_diameter
+        self.inner_diameter = inner_diameter
+        self.gap = gap
+
+    def to_inch(self):
+        self.x = self.x.to_inch().optimize()
+        self.y = self.y.to_inch().optimize()
+        self.outer_diameter = self.outer_diameter.to_inch().optimize()
+        self.inner_diameter = self.inner_diameter.to_inch().optimize()
+        self.gap = self.gap.to_inch().optimize()
+    
+    def to_metric(self):
+        self.x = self.x.to_metric().optimize()
+        self.y = self.y.to_metric().optimize()
+        self.outer_diameter = self.outer_diameter.to_metric().optimize()
+        self.inner_diameter = self.inner_diameter.to_metric().optimize()
+        self.gap = self.gap.to_metric().optimize()
+
+    def to_gerber(self, settings=None):
+        data = dict(code = self.code,
+                    x = self.x.to_gerber(settings),
+                    y = self.y.to_gerber(settings),
+                    outer_diameter = self.outer_diameter.to_gerber(settings),
+                    inner_diameter = self.inner_diameter.to_gerber(settings),
+                    gap = self.gap.to_gerber(settings),
+                    rotation = self.rotation.to_gerber(settings))
+        return '{code},{x},{y},{outer_diameter},{inner_diameter},'\
+               '{gap},{rotation}*'.format(**data)
+        
+    def to_instructions(self):
+        modifiers = [self.x, self.y, self.outer_diameter,
+                     self.inner_diameter, self.gap, self.rotation]
+        for modifier in modifiers:
+            for i in modifier.to_instructions():
+                yield i
+        yield (OpCode.PRIM, self.code)
+
+class AMVariableDef(object):
+    def __init__(self, number, value):
+        self.number = number
+        self.value = value
+
+    def to_inch(self):
+        return self
+    
+    def to_metric(self):
+        return self
+
+    def to_gerber(self, settings=None):
+        return '$%d=%s*' % (self.number, self.value.to_gerber(settings))
+
+    def to_instructions(self):
+        for i in self.value.to_instructions():
+            yield i
+        yield (OpCode.STORE, self.number)
+
+    def rotate(self, angle, center=None):
+        pass
+
+def to_primitive_defs(instructions):
+    classes = {
+        0: AMCommentPrimitiveDef,
+        1: AMCirclePrimitiveDef,
+        2: AMVectorLinePrimitiveDef,
+        20: AMVectorLinePrimitiveDef,
+        21: AMCenterLinePrimitiveDef,
+        4: AMOutlinePrimitiveDef,
+        5: AMPolygonPrimitiveDef,
+        6: AMMoirePrimitiveDef,
+        7: AMThermalPrimitiveDef,
+    }
+    for code, modifiers in eval_macro(instructions):
+        if code < 0:
+            yield AMVariableDef(-code, modifiers[0])
+        else:
+            primitive = classes[code]
+            yield primitive.from_modifiers(code, modifiers)
diff --git a/gerberex/common.py b/gerberex/common.py
new file mode 100644
index 0000000..6e8a832
--- /dev/null
+++ b/gerberex/common.py
@@ -0,0 +1,40 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+import os
+from gerber.common import loads as loads_org
+from gerber.exceptions import ParseError
+from gerber.utils import detect_file_format
+import gerber.rs274x
+import gerber.ipc356
+import gerberex.rs274x
+import gerberex.excellon
+import gerberex.dxf
+
+def read(filename, format=None):
+    with open(filename, 'rU') as f:
+        data = f.read()
+    return loads(data, filename, format=format)
+
+
+def loads(data, filename=None, format=None):
+    if os.path.splitext(filename if filename else '')[1].lower() == '.dxf':
+        return gerberex.dxf.loads(data, filename)
+
+    fmt = detect_file_format(data)
+    if fmt == 'rs274x':
+        file = gerberex.rs274x.loads(data, filename=filename)
+        return gerberex.rs274x.GerberFile.from_gerber_file(file)
+    elif fmt == 'excellon':
+        return gerberex.excellon.loads(data, filename=filename, format=format)
+    elif fmt == 'ipc_d_356':
+        return ipc356.loads(data, filename=filename)
+    else:
+        raise ParseError('Unable to detect file format')
+
+
+def rectangle(width, height, left=0, bottom=0, units='metric', draw_mode=None, filename=None):
+    return gerberex.dxf.DxfFile.rectangle(
+        width, height, left, bottom, units, draw_mode, filename)
diff --git a/gerberex/composition.py b/gerberex/composition.py
new file mode 100644
index 0000000..b5dffb1
--- /dev/null
+++ b/gerberex/composition.py
@@ -0,0 +1,192 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+import os
+from functools import reduce
+from gerber.cam import FileSettings
+from gerber.gerber_statements import EofStmt
+from gerber.excellon_statements import *
+from gerber.excellon import DrillSlot, DrillHit
+import gerberex.rs274x
+import gerberex.excellon
+import gerberex.dxf
+
+class Composition(object):
+    def __init__(self, settings = None, comments = None):
+        self.settings = settings
+        self.comments = comments if comments != None else []
+
+class GerberComposition(Composition):
+    APERTURE_ID_BIAS = 10
+
+    def __init__(self, settings=None, comments=None):
+        super(GerberComposition, self).__init__(settings, comments)
+        self.aperture_macros = {}
+        self.apertures = []
+        self.drawings = []
+
+    def merge(self, file):
+        if isinstance(file, gerberex.rs274x.GerberFile):
+            self._merge_gerber(file)
+        elif isinstance(file, gerberex.dxf.DxfFile):
+            self._merge_dxf(file)
+        else:
+            raise Exception('unsupported file type')
+
+    def dump(self, path):
+        def statements():
+            for k in self.aperture_macros:
+                yield self.aperture_macros[k]
+            for s in self.apertures:
+                yield s
+            for s in self.drawings:
+                yield s
+            yield EofStmt()
+        self.settings.notation = 'absolute'
+        self.settings.zeros = 'trailing'
+        with open(path, 'w') as f:
+            gerberex.rs274x.write_gerber_header(f, self.settings)
+            for statement in statements():
+                f.write(statement.to_gerber(self.settings) + '\n')
+
+    def _merge_gerber(self, file):
+        aperture_macro_map = {}
+        aperture_map = {}
+
+        if self.settings:
+            if self.settings.units == 'metric':
+                file.to_metric()
+            else:
+                file.to_inch()
+
+        for macro in file.aperture_macros:
+            statement = file.aperture_macros[macro]
+            name = statement.name
+            newname = self._register_aperture_macro(statement)
+            aperture_macro_map[name] = newname
+
+        for statement in file.aperture_defs:
+            if statement.param == 'AD':
+                if statement.shape in aperture_macro_map:
+                    statement.shape = aperture_macro_map[statement.shape]
+                dnum = statement.d
+                newdnum = self._register_aperture(statement)
+                aperture_map[dnum] = newdnum
+
+        for statement in file.main_statements:
+            if statement.type == 'APERTURE':
+                statement.d = aperture_map[statement.d]
+            self.drawings.append(statement)
+        
+        if not self.settings:
+            self.settings = file.context
+
+    def _merge_dxf(self, file):
+        if self.settings:
+            if self.settings.units == 'metric':
+                file.to_metric()
+            else:
+                file.to_inch()
+
+        file.dcode = self._register_aperture(file.aperture)
+        self.drawings.append(file.statements)
+
+        if not self.settings:
+            self.settings = file.settings
+
+
+    def _register_aperture_macro(self, statement):
+        name = statement.name
+        newname = name
+        offset = 0
+        while newname in self.aperture_macros:
+            offset += 1
+            newname = '%s_%d' % (name, offset)
+        statement.name = newname
+        self.aperture_macros[newname] = statement
+        return newname
+
+    def _register_aperture(self, statement):
+        statement.d = len(self.apertures) + self.APERTURE_ID_BIAS
+        self.apertures.append(statement)
+        return statement.d
+
+class DrillComposition(Composition):
+    def __init__(self, settings=None, comments=None):
+        super(DrillComposition, self).__init__(settings, comments)
+        self.tools = []
+        self.hits = []
+        self.dxf_statements = []
+    
+    def merge(self, file):
+        if isinstance(file, gerberex.excellon.ExcellonFileEx):
+            self._merge_excellon(file)
+        elif isinstance(file, gerberex.DxfFile):
+            self._merge_dxf(file)
+        else:
+            raise Exception('unsupported file type')
+
+    def dump(self, path):
+        def statements():
+            for t in self.tools:
+                yield ToolSelectionStmt(t.number).to_excellon(self.settings)
+                for h in self.hits:
+                    if h.tool.number == t.number:
+                        yield h.to_excellon(self.settings)
+                for num, statement in self.dxf_statements:
+                    if num == t.number:
+                        yield statement.to_excellon(self.settings)
+            yield EndOfProgramStmt().to_excellon()
+
+        self.settings.notation = 'absolute'
+        self.settings.zeros = 'trailing'
+        with open(path, 'w') as f:
+            gerberex.excellon.write_excellon_header(f, self.settings, self.tools)
+            for statement in statements():
+                f.write(statement + '\n')
+
+    def _merge_excellon(self, file):
+        tool_map = {}
+
+        if not self.settings:
+            self.settings = file.settings
+        else:
+            if self.settings.units == 'metric':
+                file.to_metric()
+            else:
+                file.to_inch()
+
+        for tool in iter(file.tools.values()):
+            num = tool.number
+            tool_map[num] = self._register_tool(tool)
+        
+        for hit in file.hits:
+            hit.tool = tool_map[hit.tool.number]
+            self.hits.append(hit)
+    
+    def _merge_dxf(self, file):
+        if not self.settings:
+            self.settings = file.settings
+        else:
+            if self.settings.units == 'metric':
+                file.to_metric()
+            else:
+                file.to_inch()
+
+        tool = self._register_tool(ExcellonTool(self.settings, number=1, diameter=file.width))
+        self.dxf_statements.append((tool.number, file.statements))
+
+    def _register_tool(self, tool):
+        for existing in self.tools:
+            if existing.equivalent(tool):
+                return existing
+        new_tool = ExcellonTool.from_tool(tool)
+        new_tool.settings = self.settings
+        def toolnums():
+            for tool in self.tools:
+                yield tool.number
+        max_num = reduce(lambda x, y: x if x > y else y, toolnums(), 0)
+        new_tool.number = max_num + 1
+        self.tools.append(new_tool)
+        return new_tool
diff --git a/gerberex/dxf.py b/gerberex/dxf.py
new file mode 100644
index 0000000..2341092
--- /dev/null
+++ b/gerberex/dxf.py
@@ -0,0 +1,796 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+import io, sys
+from math import pi, cos, sin, tan, atan, atan2, acos, asin, sqrt
+import dxfgrabber
+from gerber.cam import CamFile, FileSettings
+from gerber.utils import inch, metric, write_gerber_value, rotate_point
+from gerber.gerber_statements import ADParamStmt
+from gerber.excellon_statements import ExcellonTool
+from gerber.excellon_statements import CoordinateStmt
+from gerberex.utility import is_equal_point, is_equal_value
+from gerberex.dxf_path import generate_paths, judge_containment
+from gerberex.excellon import write_excellon_header
+from gerberex.rs274x import write_gerber_header
+
+ACCEPTABLE_ERROR = 0.001
+
+def _normalize_angle(start_angle, end_angle):
+    angle = end_angle - start_angle
+    if angle > 0:
+        start = start_angle % 360
+    else:
+        angle = -angle
+        start = end_angle % 360
+    angle = min(angle, 360)
+    start = start - 360 if  start > 180 else start
+
+    regions = []
+    while angle > 0:
+        end = start + angle
+        if  end <= 180:
+            regions.append((start * pi / 180, end * pi / 180))
+            angle = 0
+        else:
+            regions.append((start * pi / 180, pi))
+            angle = end - 180
+            start = -180
+    return regions
+
+def _intersections_of_line_and_circle(start, end, center, radius, error_range):
+    x1 = start[0] - center[0]
+    y1 = start[1] - center[1]
+    x2 = end[0] - center[0]
+    y2 = end[1] - center[1]
+
+    dx = x2 - x1
+    dy = y2 - y1
+    dr = sqrt(dx * dx + dy * dy)
+    D = x1 * y2 - x2 * y1
+
+    distance = abs(dy * x1 - dx * y1) / dr
+
+    D2 = D * D
+    dr2 = dr * dr
+    r2 = radius * radius
+    delta = r2 * dr2 - D2
+    if distance > radius - error_range and distance < radius + error_range:
+        delta = 0
+    if delta < 0:
+        return None
+
+    sqrt_D = sqrt(delta)
+    E_x = -dx * sqrt_D if dy < 0 else dx * sqrt_D
+    E_y = abs(dy) * sqrt_D
+
+    p1_x = (D * dy + E_x) / dr2
+    p2_x = (D * dy - E_x) / dr2
+    p1_y = (-D * dx + E_y) / dr2
+    p2_y = (-D * dx - E_y) / dr2
+
+    p1_angle = atan2(p1_y, p1_x)
+    p2_angle = atan2(p2_y, p2_x)
+    if dx == 0: 
+        p1_t = (p1_y - y1) / dy
+        p2_t = (p2_y - y1) / dy
+    else:
+        p1_t = (p1_x - x1) / dx
+        p2_t = (p2_x - x1) / dx
+
+    if delta == 0:
+        return (
+            (p1_x + center[0], p1_y + center[1]),
+            None,
+            p1_angle, None,
+            p1_t, None
+        )
+    else:
+        return (
+            (p1_x + center[0], p1_y + center[1]),
+            (p2_x + center[0], p2_y + center[1]),
+            p1_angle, p2_angle,
+            p1_t, p2_t
+        )
+
+class DxfStatement(object):
+    def __init__(self, entity):
+        self.entity = entity
+        self.start = None
+        self.end = None
+        self.is_closed = False
+
+    def to_inch(self):
+        pass
+    
+    def to_metric(self):
+        pass
+
+    def is_equal_to(self, target, error_range=0):
+        return False
+
+    def reverse(self):
+        raise Exception('Not implemented')
+
+    def offset(self, offset_x, offset_y):
+        raise Exception('Not supported')
+    
+    def rotate(self, angle, center=(0, 0)):
+        raise Exception('Not supported')
+
+
+class DxfLineStatement(DxfStatement):
+    @classmethod
+    def from_entity(cls, entity):
+        start = (entity.start[0], entity.start[1])
+        end = (entity.end[0], entity.end[1])
+        return cls(entity, start, end)
+
+    @property
+    def bounding_box(self):
+        return (min(self.start[0], self.end[0]),
+                min(self.start[1], self.end[1]),
+                max(self.start[0], self.end[0]),
+                max(self.start[1], self.end[1]))
+
+    def __init__(self, entity, start, end):
+        super(DxfLineStatement, self).__init__(entity)
+        self.start = start
+        self.end = end
+
+    def to_inch(self):
+        self.start = (
+            inch(self.start[0]), inch(self.start[1]))
+        self.end = (
+            inch(self.end[0]), inch(self.end[1]))
+
+    def to_metric(self):
+        self.start = (
+            metric(self.start[0]), metric(self.start[1]))
+        self.end = (
+            metric(self.end[0]), metric(self.end[1]))
+
+    def is_equal_to(self, target, error_range=0):
+        if not isinstance(target, DxfLineStatement):
+            return False
+        return (is_equal_point(self.start, target.start, error_range) and \
+                is_equal_point(self.end, target.end, error_range)) or \
+               (is_equal_point(self.start, target.end, error_range) and \
+                is_equal_point(self.end, target.start, error_range))
+
+    def reverse(self):
+        pt = self.start
+        self.start = self.end
+        self.end = pt
+
+    def dots(self, pitch, width, offset=0):
+        x0, y0 = self.start
+        x1, y1 = self.end
+        y1 = self.end[1]
+        xp = x1 - x0
+        yp = y1 - y0
+        l = sqrt(xp * xp + yp * yp)
+        xd = xp * pitch / l
+        yd = yp * pitch / l
+        x0 += xp * offset / l
+        y0 += yp * offset / l
+
+        if offset > l +  width / 2:
+            return (None, offset - l)
+        else:
+            d = offset;
+            while d < l + width / 2:
+                yield ((x0, y0), d - l)
+                x0 += xd
+                y0 += yd
+                d += pitch
+
+    def offset(self, offset_x, offset_y):
+        self.start = (self.start[0] + offset_x, self.start[1] + offset_y)
+        self.end = (self.end[0] + offset_x, self.end[1] + offset_y)
+
+    def rotate(self, angle, center=(0, 0)):
+        self.start = rotate_point(self.start, angle, center)
+        self.end = rotate_point(self.end, angle, center)
+    
+    def intersections_with_halfline(self, point_from, point_to, error_range):
+        denominator = (self.end[0] - self.start[0]) * (point_to[1] - point_from[1]) - \
+                      (self.end[1] - self.start[1]) * (point_to[0] - point_from[0])
+        de = error_range * error_range
+        if denominator >= -de and denominator <= de:
+            return []
+        from_dx = point_from[0] - self.start[0]
+        from_dy = point_from[1] - self.start[1]
+        r = ((point_to[1] - point_from[1]) * from_dx - 
+             (point_to[0] - point_from[0]) * from_dy) / denominator
+        s = ((self.end[1] - self.start[1]) * from_dx -
+             (self.end[0] - self.start[0]) * from_dy) / denominator
+        dx = (self.end[0] - self.start[0])
+        dy = (self.end[1] - self.start[1])
+        le = error_range / sqrt(dx * dx + dy * dy)
+        if s < 0 or r < -le or r > 1 + le:
+            return []
+        
+        pt = (self.start[0] + (self.end[0] - self.start[0]) * r,
+              self.start[1] + (self.end[1] - self.start[1]) * r)
+        if is_equal_point(pt, self.start, error_range):
+            return []
+        else:
+            return [pt]
+
+    def intersections_with_arc(self, center, radius, angle_regions, error_range):
+        intersection = \
+            _intersections_of_line_and_circle(self.start, self.end, center, radius, error_range)
+        if intersection is None:
+            return []
+        else:
+            p1, p2, p1_angle, p2_angle, p1_t, p2_t = intersection
+
+        pts = []
+        if p1_t >= 0 and p1_t <= 1:
+            for region in angle_regions:
+                if p1_angle >= region[0] and p1_angle <= region[1]:
+                    pts.append(p1)
+                    break
+        if p2 is not None and p2_t >= 0 and p2_t <= 1:
+            for region in angle_regions:
+                if p2_angle >= region[0] and p2_angle <= region[1]:
+                    pts.append(p2)
+                    break
+
+        return pts
+
+class DxfArcStatement(DxfStatement):
+    def __init__(self, entity):
+        super(DxfArcStatement, self).__init__(entity)
+        if entity.dxftype == 'CIRCLE':
+            self.radius = self.entity.radius
+            self.center = (self.entity.center[0], self.entity.center[1])
+            self.start = (self.center[0] + self.radius, self.center[1])
+            self.end = self.start
+            self.start_angle = 0
+            self.end_angle = 360
+            self.is_closed = True
+        elif entity.dxftype == 'ARC':
+            self.start_angle = self.entity.start_angle
+            self.end_angle = self.entity.end_angle
+            self.radius = self.entity.radius
+            self.center = (self.entity.center[0], self.entity.center[1])
+            self.start = (
+                self.center[0] + self.radius * cos(self.start_angle / 180. * pi),
+                self.center[1] + self.radius * sin(self.start_angle / 180. * pi),
+            )
+            self.end = (
+                self.center[0] + self.radius * cos(self.end_angle / 180. * pi),
+                self.center[1] + self.radius * sin(self.end_angle / 180. * pi),
+            )
+            angle = self.end_angle - self.start_angle
+            self.is_closed = angle >= 360 or angle <= -360
+        else:
+            raise Exception('invalid DXF type was specified')
+        self.angle_regions = _normalize_angle(self.start_angle, self.end_angle)
+
+    @property
+    def bounding_box(self):
+        return (self.center[0] - self.radius, self.center[1] - self.radius,
+                self.center[0] + self.radius, self.center[1] + self.radius)
+
+    def to_inch(self):
+        self.radius = inch(self.radius)
+        self.center = (inch(self.center[0]), inch(self.center[1]))
+        self.start = (inch(self.start[0]), inch(self.start[1]))
+        self.end = (inch(self.end[0]), inch(self.end[1]))
+
+    def to_metric(self):
+        self.radius = metric(self.radius)
+        self.center = (metric(self.center[0]), metric(self.center[1]))
+        self.start = (metric(self.start[0]), metric(self.start[1]))
+        self.end = (metric(self.end[0]), metric(self.end[1]))
+
+    def is_equal_to(self, target, error_range=0):
+        if not isinstance(target, DxfArcStatement):
+            return False
+        aerror_range = error_range / pi * self.radius * 180
+        return is_equal_point(self.center, target.center, error_range) and \
+               is_equal_value(self.radius, target.radius, error_range) and \
+               ((is_equal_value(self.start_angle, target.start_angle, aerror_range) and 
+                 is_equal_value(self.end_angle, target.end_angle, aerror_range)) or
+                (is_equal_value(self.start_angle, target.end_angle, aerror_range) and
+                 is_equal_value(self.end_angle, target.end_angle, aerror_range)))
+
+    def reverse(self):
+        tmp = self.start_angle
+        self.start_angle = self.end_angle
+        self.end_angle = tmp
+        tmp = self.start
+        self.start = self.end
+        self.end = tmp
+
+    def dots(self, pitch, width, offset=0):
+        angle = self.end_angle - self.start_angle
+        afactor = 1 if angle > 0 else -1
+        aangle = angle * afactor
+        L = 2 * pi * self.radius
+        l = L * aangle / 360
+        pangle = pitch / L * 360
+        wangle = width / L * 360
+        oangle = offset / L * 360
+
+        if offset > l + width / 2:
+            yield (None, offset - l)
+        else:
+            da = oangle
+            while da < aangle + wangle / 2:
+                cangle = self.start_angle + da * afactor
+                x = self.radius * cos(cangle / 180 * pi) + self.center[0]
+                y = self.radius * sin(cangle / 180 * pi) + self.center[1]
+                remain = (da - aangle) / 360 * L
+                yield((x, y), remain)
+                da += pangle
+
+    def offset(self, offset_x, offset_y):
+        self.center = (self.center[0] + offset_x, self.center[1] + offset_y)
+        self.start = (self.start[0] + offset_x, self.start[1] + offset_y)
+        self.end = (self.end[0] + offset_x, self.end[1] + offset_y)
+
+    def rotate(self, angle, center=(0, 0)):
+        self.start_angle += angle
+        self.end_angle += angle
+        self.center = rotate_point(self.center, angle, center)
+        self.start = rotate_point(self.start, angle, center)
+        self.end = rotate_point(self.end, angle, center)
+        self.angle_regions = _normalize_angle(self.start_angle, self.end_angle)
+
+    def intersections_with_halfline(self, point_from, point_to, error_range):
+        intersection = \
+            _intersections_of_line_and_circle(
+                point_from, point_to, self.center, self.radius, error_range)
+        if intersection is None:
+            return []
+        else:
+            p1, p2, p1_angle, p2_angle, p1_t, p2_t = intersection
+        
+        if is_equal_point(p1, self.start, error_range):
+            p1 = None
+        elif p2 is not None and is_equal_point(p2, self.start, error_range):
+            p2 = None
+
+        def is_contained(angle, region, error):
+            if angle >= region[0] - error and angle <= region[1] + error:
+                return True
+            if angle < 0 and region[1] > 0:
+                angle = angle + 2 * pi
+            elif angle > 0 and region[0] < 0:
+                angle = angle - 2 * pi
+            return  angle >= region[0] - error and angle <= region[1] + error
+            
+        aerror = error_range * self.radius
+        pts = []
+        if p1 is not None and p1_t >= 0 and not is_equal_point(p1, self.start, error_range):
+            for region in self.angle_regions:
+                if is_contained(p1_angle, region, aerror):
+                    pts.append(p1)
+                    break
+        if p2 is not None and p2_t >= 0 and not is_equal_point(p2, self.start, error_range):
+            for region in self.angle_regions:
+                if is_contained(p2_angle, region, aerror):
+                    pts.append(p2)
+                    break
+
+        return pts
+
+    def intersections_with_arc(self, center, radius, angle_regions, error_range):
+        x1 = center[0] - self.center[0]
+        y1 = center[1] - self.center[1]
+        r1 = self.radius
+        r2 = radius
+        cd_sq = x1 * x1 + y1 * y1
+        cd = sqrt(cd_sq)
+        rd = abs(r1 - r2)
+
+        if (cd >= 0 and cd <= rd) or cd >= r1 + r2:
+            return []
+        
+        A = (cd_sq + r1 * r1 - r2 * r2) / 2
+        scale = sqrt(cd_sq * r1 * r1 - A * A) / cd_sq
+        xl = A * x1 / cd_sq
+        xr = y1 * scale
+        yl = A * y1 / cd_sq
+        yr = x1 * scale
+
+        pt1_x = xl + xr
+        pt1_y = yl - yr
+        pt2_x = xl - xr
+        pt2_y = yl + yr
+        pt1_angle1 = atan2(pt1_y, pt1_x)
+        pt1_angle2 = atan2(pt1_y - y1, pt1_x - x1)
+        pt2_angle1 = atan2(pt2_y, pt2_x)
+        pt2_angle2 = atan2(pt2_y - y1, pt2_x - x1)
+
+        aerror = error_range * self.radius
+        pts=[]
+        for region in self.angle_regions:
+            if pt1_angle1 >= region[0] and pt1_angle1 <= region[1]:
+                for region in angle_regions:
+                    if pt1_angle2 >= region[0] - aerror and pt1_angle2 <= region[1] + aerror:
+                        pts.append((pt1_x + self.center[0], pt1_y + self.center[1]))
+                        break
+                break
+        for region in self.angle_regions:
+            if pt2_angle1 >= region[0] and pt2_angle1 <= region[1]:
+                for region in angle_regions:
+                    if pt2_angle2 >= region[0] - aerror and pt2_angle2 <= region[1] + aerror:
+                        pts.append((pt2_x + self.center[0], pt2_y + self.center[1]))
+                        break
+                break
+        return pts
+
+class DxfPolylineStatement(DxfStatement):
+    def __init__(self, entity):
+        super(DxfPolylineStatement, self).__init__(entity)
+        self.start = (self.entity.points[0][0], self.entity.points[0][1])
+        self.is_closed = self.entity.is_closed
+        if self.is_closed:
+            self.end = self.start
+        else:
+            self.end = (self.entity.points[-1][0], self.entity.points[-1][1])
+
+    def disassemble(self):
+        class Item:
+            pass
+
+        def ptseq():
+            for i in range(1, len(self.entity.points)):
+                yield i
+            if self.entity.is_closed:
+                yield 0
+
+        x0 = self.entity.points[0][0]
+        y0 = self.entity.points[0][1]
+        b = self.entity.bulge[0]
+        for idx in ptseq():
+            pt = self.entity.points[idx]
+            x1 = pt[0]
+            y1 = pt[1]
+            if b == 0:
+                item = Item()
+                item.dxftype = 'LINE'
+                item.start = (x0, y0)
+                item.end = (x1, y1)
+                item.is_closed = False
+                yield DxfLineStatement.from_entity(item)
+            else:
+                ang = 4 * atan(b)
+                xm = x0 + x1
+                ym = y0 + y1
+                t = 1 / tan(ang / 2)
+                xc = (xm - t * (y1 - y0)) / 2
+                yc = (ym + t * (x1 - x0)) / 2
+                r = sqrt((x0 - xc)*(x0 - xc) + (y0 - yc)*(y0 - yc))
+                rx0 = x0 - xc
+                ry0 = y0 - yc
+                rc = max(min(rx0 / r, 1.0), -1.0)
+                start_angle = acos(rc) if ry0 > 0 else 2 * pi - acos(rc)
+                start_angle *= 180 / pi
+                end_angle = start_angle + ang * 180 / pi
+
+                item = Item()
+                item.dxftype = 'ARC'
+                item.start = (x0, y0)
+                item.end = (x1, y1)
+                item.start_angle = start_angle
+                item.end_angle = end_angle
+                item.radius = r
+                item.center = (xc, yc)
+                item.is_closed = end_angle - start_angle >= 360
+                yield DxfArcStatement(item)
+
+            x0 = x1
+            y0 = y1
+            b = self.entity.bulge[idx]
+
+    def to_inch(self):
+        self.start = (inch(self.start[0]), inch(self.start[1]))
+        self.end = (inch(self.end[0]), inch(self.end[1]))
+        for idx in range(0, len(self.entity.points)):
+            self.entity.points[idx] = (
+                inch(self.entity.points[idx][0]), inch(self.entity.points[idx][1]))
+
+    def to_metric(self):
+        self.start = (metric(self.start[0]), metric(self.start[1]))
+        self.end = (metric(self.end[0]), metric(self.end[1]))
+        for idx in range(0, len(self.entity.points)):
+            self.entity.points[idx] = (
+                metric(self.entity.points[idx][0]), metric(self.entity.points[idx][1]))
+    
+    def offset(self, offset_x, offset_y):
+        for idx in range(len(self.entity.points)):
+            self.entity.points[idx] = (
+                self.entity.points[idx][0] + offset_x, self.entity.points[idx][1] + offset_y)
+
+    def rotate(self, angle, center=(0, 0)):
+        for idx in range(len(self.entity.points)):
+            self.entity.points[idx] = rotate_point(self.entity.points[idx], angle, center)
+
+class DxfStatements(object):
+    def __init__(self, statements, units, dcode=10, draw_mode=None, fill_mode=None):
+        if draw_mode is None:
+            draw_mode = DxfFile.DM_LINE
+        if fill_mode is None:
+            fill_mode = DxfFile.FM_TURN_OVER
+        self._units = units
+        self.dcode = dcode
+        self.draw_mode = draw_mode
+        self.fill_mode = fill_mode
+        self.pitch = inch(1) if self._units == 'inch' else 1
+        self.width = 0
+        self.error_range = inch(ACCEPTABLE_ERROR) if self._units == 'inch' else ACCEPTABLE_ERROR
+        self.statements = list(filter(
+            lambda i: not (isinstance(i, DxfLineStatement) and \
+                          is_equal_point(i.start, i.end, self.error_range)),
+            statements
+        ))
+        self.close_paths, self.open_paths = generate_paths(self.statements, self.error_range)
+        self.sorted_close_paths = []
+        self.polarity = True # True means dark, False means clear
+
+    @property
+    def units(self):
+        return _units
+
+    def _polarity_command(self, polarity=None):
+        if polarity is None:
+            polarity = self.polarity
+        return '%LPD*%' if polarity else '%LPC*%'
+
+    def _prepare_sorted_close_paths(self):
+        if self.sorted_close_paths:
+            return
+        for i in range(0, len(self.close_paths)):
+            for j in range(i + 1, len(self.close_paths)):
+                containee, container = judge_containment(
+                    self.close_paths[i], self.close_paths[j], self.error_range)
+                if containee is not None:
+                    containee.containers.append(container)
+        self.sorted_close_paths = sorted(self.close_paths, key=lambda path: len(path.containers))
+
+    def to_gerber(self, settings=FileSettings()):
+        def gerbers():
+            yield 'G75*'
+            yield self._polarity_command()
+            yield 'D{0}*'.format(self.dcode)
+            if self.draw_mode == DxfFile.DM_FILL:
+                yield 'G36*'
+                if self.fill_mode == DxfFile.FM_TURN_OVER:
+                    self._prepare_sorted_close_paths()
+                    polarity = self.polarity
+                    level = 0
+                    for path in self.sorted_close_paths:
+                        if len(path.containers) > level:
+                            level = len(path.containers)
+                            polarity = not polarity
+                            yield 'G37*'
+                            yield self._polarity_command(polarity)
+                            yield 'G36*'
+                        yield path.to_gerber(settings)
+                else:
+                    for path in self.close_paths:
+                        yield path.to_gerber(settings)
+                yield 'G37*'
+            else:
+                pitch = self.pitch if self.draw_mode == DxfFile.DM_MOUSE_BITES else 0
+                for path in self.open_paths:
+                    yield path.to_gerber(settings, pitch=pitch, width=self.width)
+                for path in self.close_paths:
+                    yield path.to_gerber(settings, pitch=pitch, width=self.width)
+
+        return '\n'.join(gerbers())
+
+    def to_excellon(self, settings=FileSettings()):
+        if self.draw_mode == DxfFile.DM_FILL:
+            return
+        def drills():
+            pitch = self.pitch if self.draw_mode == DxfFile.DM_MOUSE_BITES else 0
+            for path in self.open_paths:
+                yield path.to_excellon(settings, pitch=pitch, width=self.width)
+            for path in self.close_paths:
+                yield path.to_excellon(settings, pitch=pitch, width=self.width)
+        return '\n'.join(drills())
+
+    def to_inch(self):
+        if self._units == 'metric':
+            self._units = 'inch'
+            self.pitch = inch(self.pitch)
+            self.width = inch(self.width)
+            self.error_range = inch(self.error_range)
+            for path in self.open_paths:
+                path.to_inch()
+            for path in self.close_paths:
+                path.to_inch()
+
+    def to_metric(self):
+        if self._units == 'inch':
+            self._units = 'metric'
+            self.pitch = metric(self.pitch)
+            self.width = metric(self.width)
+            self.error_range = metric(self.error_range)
+            for path in self.open_paths:
+                path.to_metric()
+            for path in self.close_paths:
+                path.to_metric()
+    
+    def offset(self, offset_x, offset_y):
+        for path in self.open_paths:
+            path.offset(offset_x, offset_y)
+        for path in self.close_paths:
+            path.offset(offset_x, offset_y)
+
+    def rotate(self, angle, center=(0, 0)):
+        for path in self.open_paths:
+            path.rotate(angle, center)
+        for path in self.close_paths:
+            path.rotate(angle, center)
+
+class DxfFile(CamFile):
+    DM_LINE = 0
+    DM_FILL = 1
+    DM_MOUSE_BITES = 2
+
+    FM_SIMPLE = 0
+    FM_TURN_OVER = 1
+
+    FT_RX274X = 0
+    FT_EXCELLON = 1
+
+    @classmethod
+    def from_dxf(cls, dxf, settings=None, draw_mode=None, filename=None):
+        fsettings = settings if settings else \
+            FileSettings(zero_suppression='leading')
+
+        if dxf.header['$INSUNITS'] == 1:
+            fsettings.units = 'inch'
+            if not settings:
+                fsettings.format = (2, 5)
+        else:
+            fsettings.units = 'metric'
+            if not settings:
+                fsettings.format = (3, 4)
+
+        statements = []
+        for entity in dxf.entities:
+            if entity.dxftype == 'LWPOLYLINE':
+                statements.append(DxfPolylineStatement(entity))
+            elif entity.dxftype == 'LINE':
+                statements.append(DxfLineStatement.from_entity(entity))
+            elif entity.dxftype == 'CIRCLE':
+                statements.append(DxfArcStatement(entity))
+            elif entity.dxftype == 'ARC':
+                statements.append(DxfArcStatement(entity))
+        
+        return cls(statements, fsettings, draw_mode, filename)
+    
+    @classmethod
+    def rectangle(cls, width, height, left=0, bottom=0, units='metric', draw_mode=None, filename=None):
+        if units == 'metric':
+            settings = FileSettings(units=units, zero_suppression='leading', format=(3,4))
+        else:
+            settings = FileSettings(units=units, zero_suppression='leading', format=(2,5))
+        statements = [
+            DxfLineStatement(None, (left, bottom), (left + width, bottom)),
+            DxfLineStatement(None, (left + width, bottom), (left + width, bottom + height)),
+            DxfLineStatement(None, (left + width, bottom + height), (left, bottom + height)),
+            DxfLineStatement(None, (left, bottom + height), (left, bottom)),
+        ]
+        return cls(statements, settings, draw_mode, filename)
+
+    def __init__(self, statements, settings=None, draw_mode=None, filename=None):
+        if not settings:
+            settings = FileSettings(units='metric', format=(3,4), zero_suppression='leading')
+        if draw_mode == None:
+            draw_mode = self.DM_LINE
+
+        super(DxfFile, self).__init__(settings=settings, filename=filename)
+        self._draw_mode = draw_mode
+        self._fill_mode = self.FM_TURN_OVER
+        
+        self.aperture = ADParamStmt.circle(dcode=10, diameter=0.0)
+        if settings.units == 'inch':
+            self.aperture.to_inch()
+        else:
+            self.aperture.to_metric()
+        self.statements = DxfStatements(
+            statements, self.units, dcode=self.aperture.d, draw_mode=self.draw_mode, fill_mode=self.filename)
+
+    @property
+    def dcode(self):
+        return self.aperture.dcode
+
+    @dcode.setter
+    def dcode(self, value):
+        self.aperture.d = value
+        self.statements.dcode = value
+
+    @property
+    def width(self):
+        return self.aperture.modifiers[0][0]
+
+    @width.setter
+    def width(self, value):
+        self.aperture.modifiers = ([float(value),],)
+        self.statements.width = value
+
+    @property
+    def draw_mode(self):
+        return self._draw_mode
+    
+    @draw_mode.setter
+    def draw_mode(self, value):
+        self._draw_mode = value
+        self.statements.draw_mode = value
+
+    @property
+    def fill_mode(self):
+        return self._fill_mode
+    
+    @fill_mode.setter
+    def fill_mode(self, value):
+        self._fill_mode = value
+        self.statements.fill_mode = value
+
+    @property
+    def pitch(self):
+        return self.statements.pitch
+    
+    @pitch.setter
+    def pitch(self, value):
+        self.statements.pitch = value
+    
+    def write(self, filename=None, filetype=FT_RX274X):
+        self.settings.notation = 'absolute'
+        self.settings.zeros = 'trailing'
+        filename = filename if filename is not None else self.filename
+        with open(filename, 'w') as f:
+            if filetype == self.FT_RX274X:
+                write_gerber_header(f, self.settings)
+                f.write(self.aperture.to_gerber(self.settings) + '\n')
+                f.write(self.statements.to_gerber(self.settings) + '\n')
+                f.write('M02*\n')
+            else:
+                tools = [ExcellonTool(self.settings, number=1, diameter=self.width)]
+                write_excellon_header(f, self.settings, tools)
+                f.write('T01\n')
+                f.write(self.statements.to_excellon(self.settings) + '\n')
+                f.write('M30\n')
+
+
+    def to_inch(self):
+        if self.units == 'metric':
+            self.aperture.to_inch()
+            self.statements.to_inch()
+            self.pitch = inch(self.pitch)
+            self.units = 'inch'
+
+    def to_metric(self):
+        if self.units == 'inch':
+            self.aperture.to_metric()
+            self.statements.to_metric()
+            self.pitch = metric(self.pitch)
+            self.units = 'metric'
+
+    def offset(self, offset_x, offset_y):
+        self.statements.offset(offset_x, offset_y)
+    
+    def rotate(self, angle, center=(0, 0)):
+        self.statements.rotate(angle, center)
+
+    def negate_polarity(self):
+        self.statements.polarity = not self.statements.polarity
+
+def loads(data, filename=None):
+    if sys.version_info.major == 2:
+        data = unicode(data)
+    stream = io.StringIO(data)
+    dxf = dxfgrabber.read(stream)
+    return DxfFile.from_dxf(dxf)
diff --git a/gerberex/dxf_path.py b/gerberex/dxf_path.py
new file mode 100644
index 0000000..960b054
--- /dev/null
+++ b/gerberex/dxf_path.py
@@ -0,0 +1,412 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+from gerber.utils import inch, metric, write_gerber_value
+from gerber.cam import FileSettings
+from gerberex.utility import is_equal_point, is_equal_value, normalize_vec2d, dot_vec2d
+from gerberex.excellon import CoordinateStmtEx
+
+class DxfPath(object):
+    def __init__(self, statements, error_range=0):
+        self.statements = statements
+        self.error_range = error_range
+        self.bounding_box = statements[0].bounding_box
+        self.containers = []
+        for statement in statements[1:]:
+            self._merge_bounding_box(statement.bounding_box)
+    
+    @property
+    def start(self):
+        return self.statements[0].start
+    
+    @property
+    def end(self):
+        return self.statements[-1].end
+
+    @property
+    def is_closed(self):
+        if len(self.statements) == 1:
+            return self.statements[0].is_closed
+        else:
+            return is_equal_point(self.start, self.end, self.error_range)
+    
+    def is_equal_to(self, target, error_range=0):
+        if not isinstance(target, DxfPath):
+            return False
+        if len(self.statements) != len(target.statements):
+            return False
+        if is_equal_point(self.start, target.start, error_range) and \
+           is_equal_point(self.end, target.end, error_range):
+            for i in range(0, len(self.statements)):
+               if not self.statements[i].is_equal_to(target.statements[i], error_range):
+                   return False
+            return True
+        elif is_equal_point(self.start, target.end, error_range) and \
+             is_equal_point(self.end, target.start, error_range):
+            for i in range(0, len(self.statements)):
+               if not self.statements[i].is_equal_to(target.statements[-1 - i], error_range):
+                   return False
+            return True
+        return False
+    
+    def contain(self, target, error_range=0):
+        for statement in self.statements:
+            if statement.is_equal_to(target, error_range):
+                return True
+        else:
+            return False
+
+    def to_inch(self):
+        self.error_range = inch(self.error_range)
+        for statement in self.statements:
+            statement.to_inch()
+
+    def to_metric(self):
+        self.error_range = metric(self.error_range)
+        for statement in self.statements:
+            statement.to_metric()
+
+    def offset(self, offset_x, offset_y):
+        for statement in self.statements:
+            statement.offset(offset_x, offset_y)
+
+    def rotate(self, angle, center=(0, 0)):
+        for statement in self.statements:
+            statement.rotate(angle, center)
+
+    def reverse(self):
+        rlist = []
+        for statement in reversed(self.statements):
+            statement.reverse()
+            rlist.append(statement)
+        self.statements = rlist
+    
+    def merge(self, element, error_range=0):
+        if self.is_closed or element.is_closed:
+            return False
+        if not error_range:
+            error_range = self.error_range
+        if is_equal_point(self.end, element.start, error_range):
+            return self._append_at_end(element, error_range)
+        elif is_equal_point(self.end, element.end, error_range):
+            element.reverse()
+            return self._append_at_end(element, error_range)
+        elif is_equal_point(self.start, element.end, error_range):
+            return self._insert_on_top(element, error_range)
+        elif is_equal_point(self.start, element.start, error_range):
+            element.reverse()
+            return self._insert_on_top(element, error_range)
+        else:
+            return False
+    
+    def _append_at_end(self, element, error_range=0):
+        if isinstance(element, DxfPath):
+            if self.is_equal_to(element, error_range):
+                return False
+            for i in range(0, min(len(self.statements), len(element.statements))):
+                if not self.statements[-1 - i].is_equal_to(element.statements[i]):
+                    break
+            for j in range(0, min(len(self.statements), len(element.statements))):
+                if not self.statements[j].is_equal_to(element.statements[-1 - j]):
+                    break
+            if i + j >= len(element.statements):
+                return False
+            mergee = list(element.statements)
+            if i > 0:
+                del mergee[0:i]
+                del self.statements[-i]
+            if j > 0:
+                del mergee[-j]
+                del self.statements[0:j]
+            for statement in mergee:
+                self._merge_bounding_box(statement.bounding_box)
+            self.statements.extend(mergee)
+            return True
+        else:
+            if self.statements[-1].is_equal_to(element, error_range) or \
+               self.statements[0].is_equal_to(element, error_range):
+                return False
+            self._merge_bounding_box(element.bounding_box)
+            self.statements.appen(element)
+            return True
+
+    def _insert_on_top(self, element, error_range=0):
+        if isinstance(element, DxfPath):
+            if self.is_equal_to(element, error_range):
+                return False
+            for i in range(0, min(len(self.statements), len(element.statements))):
+                if not self.statements[-1 - i].is_equal_to(element.statements[i]):
+                    break
+            for j in range(0, min(len(self.statements), len(element.statements))):
+                if not self.statements[j].is_equal_to(element.statements[-1 - j]):
+                    break
+            if i + j >= len(element.statements):
+                return False
+            mergee = list(element.statements)
+            if i > 0:
+                del mergee[0:i]
+                del self.statements[-i]
+            if j > 0:
+                del mergee[-j]
+                del self.statements[0:j]
+            self.statements[0:0] = mergee
+            return True
+        else:
+            if self.statements[-1].is_equal_to(element, error_range) or \
+               self.statements[0].is_equal_to(element, error_range):
+                return False
+            self.statements.insert(0, element)
+            return True
+
+    def _merge_bounding_box(self, box):
+        self.bounding_box = (min(self.bounding_box[0], box[0]),
+                             min(self.bounding_box[1], box[1]),
+                             max(self.bounding_box[2], box[2]),
+                             max(self.bounding_box[3], box[3]))
+
+    def may_be_in_collision(self, path):
+        if self.bounding_box[0] >= path.bounding_box[2] or \
+           self.bounding_box[1] >= path.bounding_box[3] or \
+           self.bounding_box[2] <= path.bounding_box[0] or \
+           self.bounding_box[3] <= path.bounding_box[1]:
+            return False
+        else:
+            return True
+
+    def to_gerber(self, settings=FileSettings(), pitch=0, width=0):
+        from gerberex.dxf import DxfArcStatement
+        if pitch == 0:
+            x0, y0 = self.statements[0].start
+            gerber = 'G01*\nX{0}Y{1}D02*\nG75*'.format(
+                write_gerber_value(x0, settings.format,
+                                   settings.zero_suppression),
+                write_gerber_value(y0, settings.format,
+                                   settings.zero_suppression),
+            )
+
+            for statement in self.statements:
+                x0, y0 = statement.start
+                x1, y1 = statement.end
+                if isinstance(statement, DxfArcStatement):
+                    xc, yc = statement.center
+                    gerber += '\nG{0}*\nX{1}Y{2}I{3}J{4}D01*'.format(
+                        '03' if statement.end_angle > statement.start_angle else '02',
+                        write_gerber_value(x1, settings.format,
+                                           settings.zero_suppression),
+                        write_gerber_value(y1, settings.format,
+                                           settings.zero_suppression),
+                        write_gerber_value(xc - x0, settings.format,
+                                           settings.zero_suppression),
+                        write_gerber_value(yc - y0, settings.format,
+                                           settings.zero_suppression)
+                    )
+                else:
+                    gerber += '\nG01*\nX{0}Y{1}D01*'.format(
+                        write_gerber_value(x1, settings.format,
+                                           settings.zero_suppression),
+                        write_gerber_value(y1, settings.format,
+                                           settings.zero_suppression),
+                    )
+        else:
+            def ploter(x, y):
+                return 'X{0}Y{1}D03*\n'.format(
+                    write_gerber_value(x, settings.format,
+                                       settings.zero_suppression),
+                    write_gerber_value(y, settings.format,
+                                          settings.zero_suppression),
+                )
+            gerber = self._plot_dots(pitch, width, ploter)
+
+        return gerber
+
+    def to_excellon(self, settings=FileSettings(), pitch=0, width=0):
+        from gerberex.dxf import DxfArcStatement
+        if pitch == 0:
+            x0, y0 = self.statements[0].start
+            excellon = 'G00{0}\nM15\n'.format(
+                CoordinateStmtEx(x=x0, y=y0).to_excellon(settings))
+
+            for statement in self.statements:
+                x0, y0 = statement.start
+                x1, y1 = statement.end
+                if isinstance(statement, DxfArcStatement):
+                    i = statement.center[0] - x0
+                    j = statement.center[1] - y0
+                    excellon += '{0}{1}\n'.format(
+                        'G03' if statement.end_angle > statement.start_angle else 'G02',
+                        CoordinateStmtEx(x=x1, y=y1, i=i, j=j).to_excellon(settings))
+                else:
+                    excellon += 'G01{0}\n'.format(
+                        CoordinateStmtEx(x=x1, y=y1).to_excellon(settings))
+            
+            excellon += 'M16\nG05\n'
+        else:
+            def ploter(x, y):
+                return CoordinateStmtEx(x=x, y=y).to_excellon(settings) + '\n'
+            excellon = self._plot_dots(pitch, width, ploter)
+
+        return excellon
+
+    def _plot_dots(self, pitch, width, ploter):
+        out = ''
+        offset = 0
+        for idx in range(0, len(self.statements)):
+            statement = self.statements[idx]
+            if offset < 0:
+                offset += pitch
+            for dot, offset in statement.dots(pitch, width, offset):
+                if dot is None:
+                    break
+                if offset > 0 and (statement.is_closed or idx != len(self.statements) - 1):
+                    break
+                #if idx == len(self.statements) - 1 and statement.is_closed and offset > -pitch:
+                #    break
+                out += ploter(dot[0], dot[1])
+        return out
+
+    def intersections_with_halfline(self, point_from, point_to, error_range=0):
+        def calculator(statement):
+            return statement.intersections_with_halfline(point_from, point_to, error_range)
+        def validator(pt, statement, idx):
+            if is_equal_point(pt, statement.end, error_range) and \
+                not self._judge_cross(point_from, point_to, idx, error_range):
+                    return False
+            return True
+        return self._collect_intersections(calculator, validator, error_range)
+
+    def intersections_with_arc(self, center, radius, angle_regions, error_range=0):
+        def calculator(statement):
+            return statement.intersections_with_arc(center, radius, angle_regions, error_range)
+        return self._collect_intersections(calculator, None, error_range)
+
+    def _collect_intersections(self, calculator, validator, error_range):
+        allpts = []
+        last = allpts
+        for i in range(0, len(self.statements)):
+            statement = self.statements[i]
+            cur = calculator(statement)
+            if cur:
+                for pt in cur:
+                    for dest in allpts:
+                        if is_equal_point(pt, dest, error_range):
+                            break
+                    else:
+                        if validator is not None and not validator(pt, statement, i):
+                            continue
+                        allpts.append(pt)
+            last = cur
+        return allpts
+    
+    def _judge_cross(self, from_pt, to_pt, index, error_range):
+        standard = normalize_vec2d((to_pt[0] - from_pt[0], to_pt[1] - from_pt[1]))
+        normal = (standard[1], -standard[0])
+        def statements():
+            for i in range(index, len(self.statements)):
+                yield self.statements[i]
+            for i in range(0, index):
+                yield self.statements[i]
+        dot_standard = None
+        for statement in statements():
+            tstart = statement.start
+            tend = statement.end
+            target = normalize_vec2d((tend[0] - tstart[0], tend[1] - tstart[1]))
+            dot= dot_vec2d(normal, target)
+            if dot_standard is None:
+                dot_standard = dot
+                continue
+            if is_equal_point(standard, target, error_range):
+                continue
+            return (dot_standard > 0 and dot > 0) or (dot_standard < 0 and dot < 0)
+        raise Exception('inconsistensy is detected while cross judgement between paths')
+            
+def generate_paths(statements, error_range=0):
+    from gerberex.dxf import DxfPolylineStatement
+
+    paths = []
+    for statement in filter(lambda s: isinstance(s, DxfPolylineStatement), statements):
+        units = [unit for unit in statement.disassemble()]
+        paths.append(DxfPath(units, error_range))
+
+    unique_statements = []
+    redundant = 0
+    for statement in filter(lambda s: not isinstance(s, DxfPolylineStatement), statements):
+        for path in paths:
+            if path.contain(statement):
+                redundant += 1
+                break
+        else:
+            for target in unique_statements:
+                if statement.is_equal_to(target, error_range):
+                    redundant += 1
+                    break
+            else:
+                unique_statements.append(statement)
+
+    paths.extend([DxfPath([s], error_range) for s in unique_statements])
+
+    prev_paths_num = 0
+    while prev_paths_num != len(paths):
+        working = []
+        for i in range(len(paths)):
+            mergee = paths[i]
+            for j in range(i + 1, len(paths)):
+                target = paths[j]
+                if target.merge(mergee, error_range):
+                    break
+            else:
+                working.append(mergee)
+        prev_paths_num = len(paths)
+        paths = working
+    
+    closed_path = list(filter(lambda p: p.is_closed, paths))
+    open_path = list(filter(lambda p: not p.is_closed, paths))
+    return (closed_path, open_path)
+
+def judge_containment(path1, path2, error_range=0):
+    from gerberex.dxf import DxfArcStatement, DxfLineStatement
+
+    nocontainment = (None, None)
+    if not path1.may_be_in_collision(path2):
+        return nocontainment
+    
+    def is_in_line_segment(point_from, point_to, point):
+        dx = point_to[0] - point_from[0]
+        ratio = (point[0] - point_from[0]) / dx if dx != 0 else \
+                (point[1] - point_from[1]) / (point_to[1] - point_from[1])
+        return ratio >= 0 and ratio <= 1
+
+    def contain_in_path(statement, path):
+        if isinstance(statement, DxfLineStatement):
+            segment = (statement.start, statement.end)
+        elif isinstance(statement, DxfArcStatement):
+            if statement.start == statement.end:
+                segment = (statement.start, statement.center)
+            else:
+                segment = (statement.start, statement.end)
+        else:
+            raise Exception('invalid dxf statement type')
+        pts = path.intersections_with_halfline(segment[0], segment[1], error_range)
+        if len(pts) % 2 == 0:
+            return False
+        for pt in pts:
+            if is_in_line_segment(segment[0], segment[1], pt):
+                return False
+        if isinstance(statement, DxfArcStatement):
+            pts = path.intersections_with_arc(
+                statement.center, statement.radius, statement.angle_regions, error_range)
+            if len(pts) > 0:
+                return False
+        return True
+    
+    if contain_in_path(path1.statements[0], path2):
+        containment = [path1, path2]
+    elif contain_in_path(path2.statements[0], path1):
+        containment = [path2, path1]
+    else:
+        return nocontainment
+    for i in range(1, len(containment[0].statements)):
+        if not contain_in_path(containment[0].statements[i], containment[1]):
+            return nocontainment
+    return containment
diff --git a/gerberex/excellon.py b/gerberex/excellon.py
new file mode 100644
index 0000000..f7787d3
--- /dev/null
+++ b/gerberex/excellon.py
@@ -0,0 +1,404 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+import operator
+
+import gerber.excellon
+from gerber.excellon import ExcellonParser, detect_excellon_format, ExcellonFile, DrillHit, DrillSlot
+from gerber.excellon_statements import ExcellonStatement, UnitStmt, CoordinateStmt, UnknownStmt, \
+                                       SlotStmt, DrillModeStmt, RouteModeStmt, LinearModeStmt, \
+                                       ToolSelectionStmt, ZAxisRoutPositionStmt, \
+                                       RetractWithClampingStmt, RetractWithoutClampingStmt, \
+                                       EndOfProgramStmt
+from gerber.cam import FileSettings
+from gerber.utils import inch, metric, write_gerber_value, parse_gerber_value
+from gerberex.utility import rotate
+
+def loads(data, filename=None, settings=None, tools=None, format=None):
+    if not settings:
+        settings = FileSettings(**detect_excellon_format(data))
+        if format:
+            settings.format = format
+    gerber.excellon.CoordinateStmt = CoordinateStmtEx
+    gerber.excellon.UnitStmt = UnitStmtEx
+    file = ExcellonParser(settings, tools).parse_raw(data, filename)
+    return ExcellonFileEx.from_file(file)
+
+def write_excellon_header(file, settings, tools):
+    file.write('M48\nFMAT,2\nICI,OFF\n%s\n' %
+               UnitStmtEx(settings.units, settings.zeros, settings.format).to_excellon(settings))
+    for tool in tools:
+        file.write(tool.to_excellon(settings) + '\n')
+    file.write('%%\nG90\n%s\n' % ('M72' if settings.units == 'inch' else 'M71'))
+
+class ExcellonFileEx(ExcellonFile):
+    @classmethod
+    def from_file(cls, file):
+        def correct_statements():
+            for stmt in file.statements:
+                if isinstance(stmt, UnknownStmt):
+                    line = stmt.stmt.strip()
+                    if line[:3] == 'G02':
+                        yield CircularCWModeStmt()
+                        if len(line) > 3:
+                            yield CoordinateStmtEx.from_excellon(line[3:], file.settings)
+                    elif line[:3] == 'G03':
+                        yield CircularCCWModeStmt()
+                        if len(line) > 3:
+                            yield CoordinateStmtEx.from_excellon(line[3:], file.settings)
+                    elif line[0] == 'X' or line[0] == 'Y' or line[0] == 'A' or line[0] == 'I':
+                        yield CoordinateStmtEx.from_excellon(line, file.settings)
+                    else:
+                        yield stmt
+                else:
+                    yield stmt
+
+        def generate_hits(statements):
+            class CoordinateCtx:
+                def __init__(self, notation):
+                    self.notation = notation
+                    self.x = 0.
+                    self.y = 0.
+                    self.radius = None
+                    self.center_offset = None
+                
+                def update(self, x=None, y=None, radius=None, center_offset=None):
+                    if self.notation == 'absolute':
+                        if x is not None:
+                            self.x = x
+                        if y is not None:
+                            self.y = y
+                    else:
+                        if x is not None:
+                            self.x += x
+                        if y is not None:
+                            self.y += y
+                    if radius is not None:
+                        self.radius = radius
+                    if center_offset is not None:
+                        self.center_offset = center_offset
+                
+                def node(self, mode, center_offset):
+                    radius, offset = None, None
+                    if mode == DrillRout.MODE_CIRCULER_CW or mode == DrillRout.MODE_CIRCULER_CCW:
+                        if center_offset is None:
+                            radius = self.radius
+                            offset = self.center_offset
+                        else:
+                            radius = None
+                            offset = center_offset
+                    return DrillRout.Node(mode, self.x, self.y, radius, offset)
+
+            STAT_DRILL = 0
+            STAT_ROUT_UP = 1
+            STAT_ROUT_DOWN = 2
+
+            status = STAT_DRILL
+            current_tool = None
+            rout_mode = None
+            coordinate_ctx = CoordinateCtx(file.notation)
+            rout_nodes = []
+
+            last_position = (0., 0.)
+            last_radius = None
+            last_center_offset = None
+
+            def make_rout(status, nodes):
+                if status != STAT_ROUT_DOWN or len(nodes) == 0 or current_tool is None:
+                    return None
+                return DrillRout(current_tool, nodes)
+
+            for stmt in statements:
+                if isinstance(stmt, ToolSelectionStmt):
+                    current_tool = file.tools[stmt.tool]
+                elif isinstance(stmt, DrillModeStmt):
+                    rout = make_rout(status, rout_nodes)
+                    rout_nodes = []
+                    if rout is not None:
+                        yield rout
+                    status = STAT_DRILL
+                    rout_mode = None
+                elif isinstance(stmt, RouteModeStmt):
+                    if status == STAT_DRILL:
+                        status = STAT_ROUT_UP
+                        rout_mode = DrillRout.MODE_ROUT
+                    else:
+                        rout_mode = DrillRout.MODE_LINEAR
+
+                elif isinstance(stmt, LinearModeStmt):
+                    rout_mode = DrillRout.MODE_LINEAR
+                elif isinstance(stmt, CircularCWModeStmt):
+                    rout_mode = DrillRout.MODE_CIRCULER_CW
+                elif isinstance(stmt, CircularCCWModeStmt):
+                    rout_mode = DrillRout.MODE_CIRCULER_CCW
+                elif isinstance(stmt, ZAxisRoutPositionStmt) and status == STAT_ROUT_UP:
+                    status = STAT_ROUT_DOWN
+                elif isinstance(stmt, RetractWithClampingStmt) or isinstance(stmt, RetractWithoutClampingStmt):
+                    rout = make_rout(status, rout_nodes)
+                    rout_nodes = []
+                    if rout is not None:
+                        yield rout
+                    status = STAT_ROUT_UP
+                elif isinstance(stmt, SlotStmt):
+                    coordinate_ctx.update(stmt.x_start, stmt.y_start)
+                    x_start = coordinate_ctx.x
+                    y_start = coordinate_ctx.y
+                    coordinate_ctx.update(stmt.x_end, stmt.y_end)
+                    x_end = coordinate_ctx.x
+                    y_end = coordinate_ctx.y
+                    yield DrillSlotEx(current_tool, (x_start, y_start), 
+                                      (x_end, y_end), DrillSlotEx.TYPE_G85)
+                elif isinstance(stmt, CoordinateStmtEx):
+                    center_offset = (stmt.i, stmt.j) \
+                                    if stmt.i is not None and stmt.j is not None else None
+                    coordinate_ctx.update(stmt.x, stmt.y, stmt.radius, center_offset)
+                    if stmt.x is not None or stmt.y is not None:
+                        if status == STAT_DRILL:
+                            yield DrillHitEx(current_tool, (coordinate_ctx.x, coordinate_ctx.y))
+                        elif status == STAT_ROUT_UP:
+                            rout_nodes = [coordinate_ctx.node(DrillRout.MODE_ROUT, None)]
+                        elif status == STAT_ROUT_DOWN:
+                            rout_nodes.append(coordinate_ctx.node(rout_mode, center_offset))
+
+        statements = [s for s in correct_statements()]
+        hits = [h for h in generate_hits(statements)]
+        return cls(statements, file.tools, hits, file.settings, file.filename)
+    
+    @property
+    def primitives(self):
+        return []
+
+    def __init__(self, statements, tools, hits, settings, filename=None):
+        super(ExcellonFileEx, self).__init__(statements, tools, hits, settings, filename)
+
+    def rotate(self, angle, center=(0,0)):
+        if angle % 360 == 0:
+            return
+        for hit in self.hits:
+            hit.rotate(angle, center)
+    
+    def to_inch(self):
+        if self.units == 'metric':
+            for stmt in self.statements:
+                stmt.to_inch()
+            for tool in self.tools:
+                self.tools[tool].to_inch()
+            for hit in self.hits:
+                hit.to_inch()
+            self.units = 'inch'
+
+    def to_metric(self):
+        if self.units == 'inch':
+            for stmt in self.statements:
+                stmt.to_metric()
+            for tool in self.tools:
+                self.tools[tool].to_metric()
+            for hit in self.hits:
+                hit.to_metric()
+            self.units = 'metric'
+    
+    def write(self, filename=None):
+        self.notation = 'absolute'
+        self.zeros = 'trailing'
+        filename = filename if filename is not None else self.filename
+        with open(filename, 'w') as f:
+            write_excellon_header(f, self.settings, [self.tools[t] for t in self.tools])
+            for tool in iter(self.tools.values()):
+                f.write(ToolSelectionStmt(
+                    tool.number).to_excellon(self.settings) + '\n')
+                for hit in self.hits:
+                    if hit.tool.number == tool.number:
+                        f.write(hit.to_excellon(self.settings) + '\n')
+            f.write(EndOfProgramStmt().to_excellon() + '\n')
+
+class DrillHitEx(DrillHit):
+    def to_inch(self):
+        self.position = tuple(map(inch, self.position))
+
+    def to_metric(self):
+        self.position = tuple(map(metric, self.position))
+
+    def rotate(self, angle, center=(0, 0)):
+        self.position = rotate(*self.position, angle, center)
+
+    def to_excellon(self, settings):
+        return CoordinateStmtEx(*self.position).to_excellon(settings)
+
+class DrillSlotEx(DrillSlot):
+    def to_inch(self):
+        self.start = tuple(map(inch, self.start))
+        self.end = tuple(map(inch, self.end))
+
+    def to_metric(self):
+        self.start = tuple(map(metric, self.start))
+        self.end = tuple(map(metric, self.end))
+
+    def rotate(self, angle, center=(0,0)):
+        self.start = rotate(*self.start, angle, center)
+        self.end = rotate(*self.end, angle, center)
+
+    def to_excellon(self, settings):
+        return SlotStmt(*self.start, *self.end).to_excellon(settings)
+
+class DrillRout(object):
+    MODE_ROUT = 'G00'
+    MODE_LINEAR = 'G01'
+    MODE_CIRCULER_CW = 'G02'
+    MODE_CIRCULER_CCW = 'G03'
+
+    class Node(object):
+        def __init__(self, mode, x, y, radius=None, center_offset=None):
+            self.mode = mode
+            self.position = (x, y)
+            self.radius = radius
+            self.center_offset = center_offset
+
+        def to_excellon(self, settings):
+            center_offset = self.center_offset \
+                            if self.center_offset is not None else (None, None)
+            return self.mode + CoordinateStmtEx(
+                *self.position, self.radius, *center_offset).to_excellon(settings)
+
+    def __init__(self, tool, nodes):
+        self.tool = tool
+        self.nodes = nodes
+        self.nodes[0].mode = self.MODE_ROUT
+
+    def to_excellon(self, settings):
+        excellon = self.nodes[0].to_excellon(settings) + '\nM15\n'
+        for node in self.nodes[1:]:
+            excellon += node.to_excellon(settings) + '\n'
+        excellon += 'M16\nG05'
+        return excellon
+
+    def to_inch(self):
+        for node in self.nodes:
+            node.position = tuple(map(inch, node.position))
+            node.radius = inch(
+                node.radius) if node.radius is not None else None
+            if node.center_offset is not None:
+                node.center_offset = tuple(map(inch, node.center_offset))
+
+    def to_metric(self):
+        for node in self.nodes:
+            node.position = tuple(map(metric, node.position))
+            node.radius = metric(
+                node.radius) if node.radius is not None else None
+            if node.center_offset is not None:
+                node.center_offset = tuple(map(metric, node.center_offset))
+
+    def offset(self, x_offset=0, y_offset=0):
+        for node in self.nodes:
+            node.position = tuple(map(operator.add, node.position, (x_offset, y_offset)))
+
+    def rotate(self, angle, center=(0, 0)):
+        for node in self.nodes:
+            node.position = rotate(*node.position, angle, center)
+            if node.center_offset is not None:
+                node.center_offset = rotate(*node.center_offset, angle, (0., 0.))
+
+class UnitStmtEx(UnitStmt):
+    @classmethod
+    def from_statement(cls, stmt):
+        return cls(units=stmt.units, zeros=stmt.zeros, format=stmt.format, id=stmt.id)
+
+    def __init__(self, units='inch', zeros='leading', format=None, **kwargs):
+        super(UnitStmtEx, self).__init__(units, zeros, format, **kwargs)
+    
+    def to_excellon(self, settings=None):
+        format = settings.format if settings else self.format
+        stmt = None
+        if self.units == 'inch' and format == (2, 4):
+            stmt = 'INCH,%s' % ('LZ' if self.zeros == 'leading' else 'TZ')
+        else:
+            stmt = '%s,%s,%s.%s' % ('INCH' if self.units == 'inch' else 'METRIC',
+                              'LZ' if self.zeros == 'leading' else 'TZ',
+                              '0' * format[0], '0' * format[1])
+        return stmt
+
+class CircularCWModeStmt(ExcellonStatement):
+
+    def __init__(self, **kwargs):
+        super(CircularCWModeStmt, self).__init__(**kwargs)
+
+    def to_excellon(self, settings=None):
+        return 'G02'
+
+class CircularCCWModeStmt(ExcellonStatement):
+
+    def __init__(self, **kwargs):
+        super(CircularCCWModeStmt, self).__init__(**kwargs)
+
+    def to_excellon(self, settings=None):
+        return 'G02'
+
+class CoordinateStmtEx(CoordinateStmt):
+    @classmethod
+    def from_statement(cls, stmt):
+        newStmt = cls(x=stmt.x, y=stmt.y)
+        newStmt.radius = stmt.radius if isinstance(stmt, CoordinateStmtEx) else None
+        return newStmt
+
+    @classmethod
+    def from_excellon(cls, line, settings, **kwargs):
+        stmt = None
+        if 'A' in line:
+            parts = line.split('A')
+            stmt = cls.from_statement(CoordinateStmt.from_excellon(parts[0], settings)) \
+                   if parts[0] != '' else cls()
+            stmt.radius = parse_gerber_value(
+                parts[1], settings.format, settings.zero_suppression)
+        elif 'I' in line:
+            jparts = line.split('J')
+            iparts = jparts[0].split('I')
+            stmt = cls.from_statement(CoordinateStmt.from_excellon(iparts[0], settings)) \
+                   if iparts[0] != '' else cls()
+            stmt.i = parse_gerber_value(
+                iparts[1], settings.format, settings.zero_suppression)
+            stmt.j = parse_gerber_value(
+                jparts[1], settings.format, settings.zero_suppression)
+        else:
+            stmt = cls.from_statement(CoordinateStmt.from_excellon(line, settings))
+            
+        return stmt
+
+    def __init__(self, x=None, y=None, radius=None, i=None, j=None, **kwargs):
+        super(CoordinateStmtEx, self).__init__(x, y, **kwargs)
+        self.radius = radius
+        self.i = i
+        self.j = j
+    
+    def to_excellon(self, settings):
+        stmt = ''
+        if self.x is not None:
+            stmt += 'X%s' % write_gerber_value(self.x, settings.format,
+                                               settings.zero_suppression)
+        if self.y is not None:
+            stmt += 'Y%s' % write_gerber_value(self.y, settings.format,
+                                               settings.zero_suppression)
+        if self.radius is not None:
+            stmt += 'A%s' % write_gerber_value(self.radius, settings.format,
+                                               settings.zero_suppression)
+        elif self.i is not None and self.j is not None:
+            stmt += 'I%sJ%s' % (write_gerber_value(self.i, settings.format,
+                                                   settings.zero_suppression),
+                                write_gerber_value(self.j, settings.format,
+                                                   settings.zero_suppression))
+        return stmt
+
+    def __str__(self):
+        coord_str = ''
+        if self.x is not None:
+            coord_str += 'X: %g ' % self.x
+        if self.y is not None:
+            coord_str += 'Y: %g ' % self.y
+        if self.radius is not None:
+            coord_str += 'A: %g ' % self.radius
+        if self.i is not None:
+            coord_str += 'I: %g ' % self.i
+        if self.j is not None:
+            coord_str += 'J: %g ' % self.j
+
+        return '<Coordinate Statement: %s>' % (coord_str)
diff --git a/gerberex/gerber_statements.py b/gerberex/gerber_statements.py
new file mode 100644
index 0000000..c2eb565
--- /dev/null
+++ b/gerberex/gerber_statements.py
@@ -0,0 +1,115 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+from gerber.gerber_statements import AMParamStmt, ADParamStmt
+from gerber.utils import inch, metric
+from gerberex.am_primitive import to_primitive_defs
+
+class AMParamStmtEx(AMParamStmt):
+    @classmethod
+    def from_stmt(cls, stmt):
+        return cls(stmt.param, stmt.name, stmt.macro, stmt.units)
+
+    @classmethod
+    def circle(cls, name, units):
+        return cls('AM', name, '1,1,$1,0,0,0*1,0,$2,0,0,0', units)
+
+    @classmethod
+    def rectangle(cls, name, units):
+        return cls('AM', name, '21,1,$1,$2,0,0,0*1,0,$3,0,0,0', units)
+    
+    @classmethod
+    def landscape_obround(cls, name, units):
+        return cls(
+            'AM', name,
+            '$4=$1-$2*'
+            '$5=$1-$4*'
+            '21,1,$5,$2,0,0,0*'
+            '1,1,$4,$4/2,0,0*'
+            '1,1,$4,-$4/2,0,0*'
+            '1,0,$3,0,0,0', units)
+
+    @classmethod
+    def portrate_obround(cls, name, units):
+        return cls(
+            'AM', name,
+            '$4=$2-$1*'
+            '$5=$2-$4*'
+            '21,1,$1,$5,0,0,0*'
+            '1,1,$4,0,$4/2,0*'
+            '1,1,$4,0,-$4/2,0*'
+            '1,0,$3,0,0,0', units)
+    
+    @classmethod
+    def polygon(cls, name, units):
+        return cls('AM', name, '5,1,$2,0,0,$1,$3*1,0,$4,0,0,0', units)
+
+    def __init__(self, param, name, macro, units):
+        super(AMParamStmtEx, self).__init__(param, name, macro)
+        self.units = units
+        self.primitive_defs = list(to_primitive_defs(self.instructions))
+    
+    def to_inch(self):
+        if self.units == 'metric':
+            self.units = 'inch'
+            for p in self.primitive_defs:
+                p.to_inch()
+
+    def to_metric(self):
+        if self.units == 'inch':
+            self.units = 'metric'
+            for p in self.primitive_defs:
+                p.to_metric()
+
+    def to_gerber(self, settings = None):
+        def plist():
+            for p in self.primitive_defs:
+                yield p.to_gerber(settings)
+        return "%%AM%s*\n%s%%" % (self.name, '\n'.join(plist()))
+
+    def rotate(self, angle, center=None):
+        for primitive_def in self.primitive_defs:
+            primitive_def.rotate(angle, center)
+
+class ADParamStmtEx(ADParamStmt):
+    GEOMETRIES = {
+        'C': [0,1],
+        'R': [0,1,2],
+        'O': [0,1,2],
+        'P': [0,3],
+    }
+
+    @classmethod
+    def from_stmt(cls, stmt):
+        modstr = ','.join([
+            'X'.join(['{0}'.format(x) for x in modifier])
+        for modifier in stmt.modifiers])
+        return cls(stmt.param, stmt.d, stmt.shape, modstr, stmt.units)
+
+    def __init__(self, param, d, shape, modifiers, units):
+        super(ADParamStmtEx, self).__init__(param, d, shape, modifiers)
+        self.units = units
+
+    def to_inch(self):
+        if self.units == 'inch':
+            return
+        self.units = 'inch'
+        if self.shape in self.GEOMETRIES:
+            indices = self.GEOMETRIES[self.shape]
+            self.modifiers = [tuple([
+                inch(self.modifiers[0][i]) if i in indices else self.modifiers[0][i] \
+                    for i in range(len(self.modifiers[0]))
+            ])]
+
+    def to_metric(self):
+        if self.units == 'metric':
+            return
+        self.units = 'metric'
+        if self.shape in self.GEOMETRIES:
+            indices = self.GEOMETRIES[self.shape]
+            self.modifiers = [tuple([
+                metric(self.modifiers[0][i]) if i in indices else self.modifiers[0][i] \
+                    for i in range(len(self.modifiers[0]))
+            ])]
diff --git a/gerberex/rs274x.py b/gerberex/rs274x.py
new file mode 100644
index 0000000..3a3a712
--- /dev/null
+++ b/gerberex/rs274x.py
@@ -0,0 +1,331 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+from gerber.cam import FileSettings
+import gerber.rs274x
+from gerber.gerber_statements import *
+from gerberex.gerber_statements import AMParamStmt, AMParamStmtEx, ADParamStmtEx
+from gerberex.utility import rotate
+import re
+
+def loads(data, filename=None):
+    cls = gerber.rs274x.GerberParser
+    cls.SF = \
+        r"(?P<param>SF)(A(?P<a>{decimal}))?(B(?P<b>{decimal}))?".format(decimal=cls.DECIMAL)
+    cls.PARAMS = (cls.FS, cls.MO, cls.LP, cls.AD_CIRCLE, 
+                  cls.AD_RECT, cls.AD_OBROUND, cls.AD_POLY,
+                  cls.AD_MACRO, cls.AM, cls.AS, cls.IF, cls.IN, 
+                  cls.IP, cls.IR, cls.MI, cls.OF, cls.SF, cls.LN)
+    cls.PARAM_STMT = [re.compile(r"%?{0}\*%?".format(p)) for p in cls.PARAMS]
+    return cls().parse_raw(data, filename)
+
+def write_gerber_header(file, settings):
+    file.write('%s\n%s\n%%IPPOS*%%\n' % (
+               MOParamStmt('MO', settings.units).to_gerber(settings),
+               FSParamStmt('FS', settings.zero_suppression, 
+                           settings.notation, settings.format).to_gerber(settings)))
+
+class GerberFile(gerber.rs274x.GerberFile):
+    @classmethod
+    def from_gerber_file(cls, gerber_file):
+        if not isinstance(gerber_file, gerber.rs274x.GerberFile):
+            raise Exception('only gerber.rs274x.GerberFile object is specified')
+        
+        return cls(gerber_file.statements, gerber_file.settings, gerber_file.primitives,\
+                   gerber_file.apertures, gerber_file.filename)
+
+    def __init__(self, statements, settings, primitives, apertures, filename=None):
+        super(GerberFile, self).__init__(statements, settings, primitives, apertures, filename)
+        self.context = GerberContext.from_settings(self.settings)
+        self.aperture_macros = {}
+        self.aperture_defs = []
+        self.main_statements = []
+        for stmt in self.statements:
+            type, stmts = self.context.normalize_statement(stmt)
+            if type == self.context.TYPE_AM:
+                for mdef in stmts:
+                    self.aperture_macros[mdef.name] = mdef
+            elif type == self.context.TYPE_AD:
+                self.aperture_defs.extend(stmts)
+            elif type == self.context.TYPE_MAIN:
+                self.main_statements.extend(stmts)
+        if self.context.angle != 0:
+            self.rotate(self.context.angle)
+        if self.context.is_negative:
+            self.nagate_polarity()
+        self.context.notation = 'absolute'
+        self.context.zeros = 'trailing'
+
+    def write(self, filename=None):
+        self.context.notation = 'absolute'
+        self.context.zeros = 'trailing'
+        self.context.format = self.format
+        self.units = self.units
+        filename=filename if filename is not None else self.filename
+        with open(filename, 'w') as f:
+            write_gerber_header(f, self.context)
+            for macro in self.aperture_macros:
+                f.write(self.aperture_macros[macro].to_gerber(self.context) + '\n')
+            for aperture in self.aperture_defs:
+                f.write(aperture.to_gerber(self.context) + '\n')
+            for statement in self.main_statements:
+                f.write(statement.to_gerber(self.context) + '\n')
+            f.write('M02*\n')
+
+    def to_inch(self):
+        if self.units == 'metric':
+            for macro in self.aperture_macros:
+                self.aperture_macros[macro].to_inch()
+            for aperture in self.aperture_defs:
+                aperture.to_inch()
+            for statement in self.statements:
+                statement.to_inch()
+            self.units = 'inch'
+            self.context.units = 'inch'
+
+    def to_metric(self):
+        if self.units == 'inch':
+            for macro in self.aperture_macros:
+                self.aperture_macros[macro].to_metric()
+            for aperture in self.aperture_defs:
+                aperture.to_metric()
+            for statement in self.statements:
+                statement.to_metric()
+            self.units='metric'
+            self.context.units='metric'
+
+    def offset(self, x_offset=0, y_offset=0):
+        for statement in self.main_statements:
+            if isinstance(statement, CoordStmt):
+                if statement.x is not None:
+                    statement.x += x_offset
+                if statement.y is not None:
+                    statement.y += y_offset
+        for primitive in self.primitives:
+            primitive.offset(x_offset, y_offset)
+
+    def rotate(self, angle, center=(0,0)):
+        if angle % 360 == 0:
+            return
+        self._generalize_aperture()
+        last_x = 0
+        last_y = 0
+        last_rx = 0
+        last_ry = 0
+        for name in self.aperture_macros:
+            self.aperture_macros[name].rotate(angle, center)
+        for statement in self.main_statements:
+            if isinstance(statement, CoordStmt) and statement.x != None and statement.y != None:
+                if statement.i != None and statement.j != None:
+                    cx = last_x + statement.i
+                    cy = last_y + statement.j
+                    cx, cy = rotate(cx, cy, angle, center)
+                    statement.i = cx - last_rx
+                    statement.j = cy - last_ry
+                last_x = statement.x
+                last_y = statement.y
+                last_rx, last_ry = rotate(statement.x, statement.y, angle, center)
+                statement.x = last_rx
+                statement.y = last_ry
+    
+    def nagate_polarity(self):
+        for statement in self.main_statements:
+            if isinstance(statement, LPParamStmt):
+                statement.lp = 'dark' if statement.lp == 'clear' else 'clear'
+    
+    def _generalize_aperture(self):
+        RECTANGLE = 0
+        LANDSCAPE_OBROUND = 1
+        PORTRATE_OBROUND = 2
+        POLYGON = 3
+        macro_defs = [
+            ('MACR', AMParamStmtEx.rectangle),
+            ('MACLO', AMParamStmtEx.landscape_obround),
+            ('MACPO', AMParamStmtEx.portrate_obround),
+            ('MACP', AMParamStmtEx.polygon)
+        ]
+
+        need_to_change = False
+        for statement in self.aperture_defs:
+            if isinstance(statement, ADParamStmt) and statement.shape in ['R', 'O', 'P']:
+                need_to_change = True
+        
+        if need_to_change:
+            for idx in range(0, len(macro_defs)):
+                macro_def = macro_defs[idx]
+                name = macro_def[0]
+                num = 1
+                while name in self.aperture_macros:
+                    name = '%s_%d' % (macro_def[0], num)
+                    num += 1
+                self.aperture_macros[name] = macro_def[1](name, self.units)
+                macro_defs[idx] = (name, macro_def[1])
+            for statement in self.aperture_defs:
+                if isinstance(statement, ADParamStmt):
+                    if statement.shape == 'R':
+                        statement.shape = macro_defs[RECTANGLE][0]
+                    elif statement.shape == 'O':
+                        x = statement.modifiers[0][0] \
+                            if len(statement.modifiers[0]) > 0 else 0
+                        y = statement.modifiers[0][1] \
+                            if len(statement.modifiers[0]) > 1 else 0
+                        statement.shape = macro_defs[LANDSCAPE_OBROUND][0] \
+                                          if x > y else macro_defs[PORTRATE_OBROUND][0] 
+                    elif statement.shape == 'P':
+                        statement.shape = macro_defs[POLYGON][0]
+
+class GerberContext(FileSettings):
+    TYPE_NONE = 'none'
+    TYPE_AM = 'am'
+    TYPE_AD = 'ad'
+    TYPE_MAIN = 'main'
+    IP_LINEAR = 'lenear'
+    IP_ARC = 'arc'
+    DIR_CLOCKWISE = 'cw'
+    DIR_COUNTERCLOCKWISE = 'ccw'
+
+    ignored_stmt = ('FSParamStmt', 'MOParamStmt', 'ASParamStmt',
+                    'INParamStmt', 'IPParamStmt', 'IRParamStmt',
+                    'MIParamStmt', 'OFParamStmt', 'SFParamStmt',
+                    'LNParamStmt', 'CommentStmt', 'EofStmt',)
+
+    @classmethod
+    def from_settings(cls, settings):
+        return cls(settings.notation, settings.units, settings.zero_suppression,
+                   settings.format, settings.zeros, settings.angle_units)
+
+    def __init__(self, notation='absolute', units='inch',
+                 zero_suppression=None, format=(2, 5), zeros=None,
+                 angle_units='degrees',
+                 name=None,
+                 mirror=(False, False), offset=(0., 0.), scale=(1., 1.),
+                 angle=0., axis='xy'):
+        super(GerberContext, self).__init__(notation, units, zero_suppression, 
+                                      format, zeros, angle_units)
+        self.name = name
+        self.mirror = mirror
+        self.offset = offset
+        self.scale = scale
+        self.angle = angle
+        self.axis = axis
+
+        self.matrix = (1, 0, 
+                       1, 0,
+                       1, 1)
+
+        self.is_negative = False
+        self.is_first_coordinate = True
+        self.no_polarity = True
+        self.in_single_quadrant_mode = False
+        self.op = None
+        self.interpolation = self.IP_LINEAR
+        self.direction = self.DIR_CLOCKWISE
+        self.x = 0.
+        self.y = 0.
+
+    def normalize_statement(self, stmt):
+        additional_stmts = None
+        if isinstance(stmt, INParamStmt):
+            self.name = stmt.name
+        elif isinstance(stmt, MIParamStmt):
+            self.mirror = (stmt.a, stmt.b)
+            self._update_matrix()
+        elif isinstance(stmt, OFParamStmt):
+            self.offset = (stmt.a, stmt.b)
+            self._update_matrix()
+        elif isinstance(stmt, SFParamStmt):
+            self.scale = (stmt.a, stmt.b)
+            self._update_matrix()
+        elif isinstance(stmt, ASParamStmt):
+            self.axis = 'yx' if stmt.mode == 'AYBX' else 'xy'
+            self._update_matrix()
+        elif isinstance(stmt, IRParamStmt):
+            self.angle = stmt.angle
+        elif isinstance(stmt, AMParamStmt) and not isinstance(stmt, AMParamStmtEx):
+            stmt = AMParamStmtEx.from_stmt(stmt)
+            return (self.TYPE_AM, [stmt])
+        elif isinstance(stmt, ADParamStmt) and not isinstance(stmt, AMParamStmtEx):
+            stmt = ADParamStmtEx.from_stmt(stmt)
+            return (self.TYPE_AD, [stmt])
+        elif isinstance(stmt, QuadrantModeStmt):
+            self.in_single_quadrant_mode = stmt.mode == 'single-quadrant'
+            stmt.mode = 'multi-quadrant'
+        elif isinstance(stmt, IPParamStmt):
+            self.is_negative = stmt.ip == 'negative'
+        elif isinstance(stmt, LPParamStmt):
+            self.no_polarity = False
+        elif isinstance(stmt, CoordStmt):
+            self._normalize_coordinate(stmt)
+            if self.is_first_coordinate:
+                self.is_first_coordinate = False
+                if self.no_polarity:
+                    additional_stmts = [LPParamStmt('LP', 'dark'), stmt]
+
+        if type(stmt).__name__ in self.ignored_stmt:
+            return (self.TYPE_NONE, None)
+        elif additional_stmts is not None:
+            return (self.TYPE_MAIN, additional_stmts)
+        else:
+            return (self.TYPE_MAIN, [stmt])
+
+    def _update_matrix(self):
+        if self.axis == 'xy':
+            mx = -1 if self.mirror[0] else 1
+            my = -1 if self.mirror[1] else 1
+            self.matrix = (
+                self.scale[0] * mx, self.offset[0],
+                self.scale[1] * my, self.offset[1],
+                self.scale[0] * mx, self.scale[1] * my)
+        else:
+            mx = -1 if self.mirror[1] else 1
+            my = -1 if self.mirror[0] else 1
+            self.matrix = (
+                self.scale[1] * mx, self.offset[1],
+                self.scale[0] * my, self.offset[0],
+                self.scale[1] * mx, self.scale[0] * my)
+
+    def _normalize_coordinate(self, stmt):
+        if stmt.function == 'G01' or stmt.function == 'G1':
+            self.interpolation = self.IP_LINEAR
+        elif stmt.function == 'G02' or stmt.function == 'G2':
+            self.interpolation = self.IP_ARC
+            self.direction = self.DIR_CLOCKWISE
+            if self.mirror[0] != self.mirror[1]:
+                stmt.function = 'G03'
+        elif stmt.function == 'G03' or stmt.function == 'G3':
+            self.interpolation = self.IP_ARC
+            self.direction = self.DIR_COUNTERCLOCKWISE
+            if self.mirror[0] != self.mirror[1]:
+                stmt.function = 'G02'
+        if stmt.only_function:
+            return
+
+        last_x = self.x
+        last_y = self.y
+        if self.notation == 'absolute':
+            x = stmt.x if stmt.x is not None else self.x
+            y = stmt.y if stmt.y is not None else self.y
+        else:
+            x = self.x + stmt.x if stmt.x is not None else 0
+            y = self.y + stmt.y if stmt.y is not None else 0
+        self.x, self.y = x, y
+        self.op = stmt.op if stmt.op is not None else self.op
+
+        stmt.op = self.op
+        stmt.x = self.matrix[0] * x + self.matrix[1]
+        stmt.y = self.matrix[2] * y + self.matrix[3]
+        if stmt.op == 'D01' and self.interpolation == self.IP_ARC:
+            qx, qy = 1, 1
+            if self.in_single_quadrant_mode:
+                if self.direction == self.DIR_CLOCKWISE:
+                    qx = 1 if y > last_y else -1
+                    qy = 1 if x < last_x else -1
+                else:
+                    qx = 1 if y < last_y else -1
+                    qy = 1 if x > last_x else -1
+                if last_x == x and last_y == y:
+                    qx, qy = 0, 0
+            stmt.i = qx * self.matrix[4] * stmt.i if stmt.i is not None else 0
+            stmt.j = qy * self.matrix[5] * stmt.j if stmt.j is not None else 0
diff --git a/gerberex/utility.py b/gerberex/utility.py
new file mode 100644
index 0000000..37de5e8
--- /dev/null
+++ b/gerberex/utility.py
@@ -0,0 +1,27 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2019 Hiroshi Murayama <opiopan@gmail.com>
+
+from math import cos, sin, pi, sqrt
+
+def rotate(x, y, angle, center):
+    x0 = x - center[0]
+    y0 = y - center[1]
+    angle = angle * pi / 180.0
+    return (cos(angle) * x0 - sin(angle) * y0 + center[0],
+            sin(angle) * x0 + cos(angle) * y0 + center[1])
+
+def is_equal_value(a, b, error_range=0):
+    return (a - b) * (a - b) <= error_range * error_range
+
+def is_equal_point(a, b, error_range=0):
+    return is_equal_value(a[0], b[0], error_range) and \
+        is_equal_value(a[1], b[1], error_range)
+
+def normalize_vec2d(vec):
+    length = sqrt(vec[0] * vec[0] + vec[1] * vec[1])
+    return (vec[0] / length, vec[1] / length)
+
+def dot_vec2d(vec1, vec2):
+    return vec1[0] * vec2[0] + vec1[1] * vec2[1]
\ No newline at end of file