Add support for arcs in regions.

This fixes the circular cutout issue described in #32.  Regions were previously stored as a collection of points, now they are stored as a collection of line and arc primitives.

4 files changed, 70 insertions, 49 deletions

diff --git a/gerber/primitives.py b/gerber/primitives.py
index bdd49f7..e207fa8 100644
--- a/gerber/primitives.py
+++ b/gerber/primitives.py
@@ -61,7 +61,10 @@ class Primitive(object):
                 else:

                     try:

                         if len(value) > 1:

-                            if isinstance(value[0], tuple):

+                            if hasattr(value[0], 'to_inch'):

+                                for v in value:

+                                    v.to_inch()

+                            elif isinstance(value[0], tuple):

                                 setattr(self, attr, [tuple(map(inch, point)) for point in value])

                             else:

                                 setattr(self, attr, tuple(map(inch, value)))

@@ -79,7 +82,10 @@ class Primitive(object):
                 else:

                     try:

                         if len(value) > 1:

-                            if isinstance(value[0], tuple):

+                            if hasattr(value[0], 'to_metric'):

+                                for v in value:

+                                    v.to_metric()

+                            elif isinstance(value[0], tuple):

                                 setattr(self, attr, [tuple(map(metric, point)) for point in value])

                             else:

                                 setattr(self, attr, tuple(map(metric, value)))

@@ -582,23 +588,25 @@ class Polygon(Primitive):
 class Region(Primitive):

     """

     """

-    def __init__(self, points, **kwargs):

+    def __init__(self, primitives, **kwargs):

         super(Region, self).__init__(**kwargs)

-        self.points = points

-        self._to_convert = ['points']

+        self.primitives = primitives

+        self._to_convert = ['primitives']

 

     @property

     def bounding_box(self):

-        x_list, y_list = zip(*self.points)

-        min_x = min(x_list)

-        max_x = max(x_list)

-        min_y = min(y_list)

-        max_y = max(y_list)

+        xlims, ylims = zip(*[p.bounding_box for p in self.primitives])

+        minx, maxx = zip(*xlims)

+        miny, maxy = zip(*ylims)

+        min_x = min(minx)

+        max_x = max(maxx)

+        min_y = min(miny)

+        max_y = max(maxy)

         return ((min_x, max_x), (min_y, max_y))

 

     def offset(self, x_offset=0, y_offset=0):

-        self.points = [tuple(map(add, point, (x_offset, y_offset)))

-                       for point in self.points]

+        for p in self.primitives:

+            p.offset(x_offset, y_offset)

 

 

 class RoundButterfly(Primitive):

diff --git a/gerber/render/cairo_backend.py b/gerber/render/cairo_backend.py
index 0ae5d40..a97e552 100644
--- a/gerber/render/cairo_backend.py
+++ b/gerber/render/cairo_backend.py
@@ -89,13 +89,25 @@ class GerberCairoContext(GerberContext):
         self.ctx.move_to(*end)  # ...lame

 

     def _render_region(self, region, color):

-        points = [tuple(map(mul, point, self.scale)) for point in region.points]

         self.ctx.set_source_rgba(*color, alpha=self.alpha)

-        self.ctx.set_operator(cairo.OPERATOR_OVER if (region.level_polarity == "dark" and not self.invert) else cairo.OPERATOR_CLEAR)        

+        self.ctx.set_operator(cairo.OPERATOR_OVER if (region.level_polarity == "dark" and not self.invert) else cairo.OPERATOR_CLEAR)

         self.ctx.set_line_width(0)

-        self.ctx.move_to(*points[0])

-        for point in points[1:]:

-            self.ctx.line_to(*point)

+        self.ctx.set_line_cap(cairo.LINE_CAP_ROUND)

+        self.ctx.move_to(*tuple(map(mul, region.primitives[0].start, self.scale)))

+        for p in region.primitives:

+            if isinstance(p, Line):

+                self.ctx.line_to(*tuple(map(mul, p.end, self.scale)))

+            else:

+                center = map(mul, p.center, self.scale)

+                start = map(mul, p.start, self.scale)

+                end = map(mul, p.end, self.scale)

+                radius = self.scale[0] * p.radius

+                angle1 = p.start_angle

+                angle2 = p.end_angle

+                if p.direction == 'counterclockwise':

+                    self.ctx.arc(*center, radius=radius, angle1=angle1, angle2=angle2)

+                else:

+                    self.ctx.arc_negative(*center, radius=radius, angle1=angle1, angle2=angle2)

         self.ctx.fill()

 

     def _render_circle(self, circle, color):

diff --git a/gerber/rs274x.py b/gerber/rs274x.py
index b4963d1..1df3646 100644
--- a/gerber/rs274x.py
+++ b/gerber/rs274x.py
@@ -468,22 +468,29 @@ class GerberParser(object):
             stmt.op = self.op
 
         if self.op == "D01":
-            if self.region_mode == 'on':
-                if self.current_region is None:
-                    self.current_region = [(self.x, self.y), ]
-                self.current_region.append((x, y,))
-            else:
-                start = (self.x, self.y)
-                end = (x, y)
+            start = (self.x, self.y)
+            end = (x, y)
 
-                if self.interpolation == 'linear':
+            if self.interpolation == 'linear':
+                if self.region_mode == 'off':
                     self.primitives.append(Line(start, end, self.apertures[self.aperture], level_polarity=self.level_polarity, units=self.settings.units))
                 else:
-                    i = 0 if stmt.i is None else stmt.i
-                    j = 0 if stmt.j is None else stmt.j
-                    center = (start[0] + i, start[1] + j)
+                    if self.current_region is None:
+                        self.current_region = [Line(start, end, self.apertures[self.aperture], level_polarity=self.level_polarity, units=self.settings.units),]
+                    else:    
+                        self.current_region.append(Line(start, end, self.apertures[self.aperture], level_polarity=self.level_polarity, units=self.settings.units))
+            else:
+                i = 0 if stmt.i is None else stmt.i
+                j = 0 if stmt.j is None else stmt.j
+                center = (start[0] + i, start[1] + j)
+                if self.region_mode == 'off':
                     self.primitives.append(Arc(start, end, center, self.direction, self.apertures[self.aperture], level_polarity=self.level_polarity, units=self.settings.units))
-
+                else:
+                    if self.current_region is None:
+                        self.current_region = [Arc(start, end, center, self.direction, self.apertures[self.aperture], level_polarity=self.level_polarity, units=self.settings.units),]
+                    else:
+                        self.current_region.append(Arc(start, end, center, self.direction, self.apertures[self.aperture], level_polarity=self.level_polarity, units=self.settings.units))
+                                
         elif self.op == "D02":
             pass
 
diff --git a/gerber/tests/test_primitives.py b/gerber/tests/test_primitives.py
index 67c7822..f8a32da 100644
--- a/gerber/tests/test_primitives.py
+++ b/gerber/tests/test_primitives.py
@@ -4,6 +4,7 @@
 # Author: Hamilton Kibbe <ham@hamiltonkib.be>
 from ..primitives import *
 from .tests import *
+from operator import add
 
 
 def test_primitive_smoketest():
@@ -766,38 +767,31 @@ def test_polygon_offset():
 def test_region_ctor():
     """ Test Region creation
     """
+    apt = Circle((0,0), 0)
+    lines = (Line((0,0), (1,0), apt), Line((1,0), (1,1), apt), Line((1,1), (0,1), apt), Line((0,1), (0,0), apt))
     points = ((0, 0), (1,0), (1,1), (0,1))
-    r = Region(points)
-    for i, point in enumerate(points):
-        assert_array_almost_equal(r.points[i], point)
+    r = Region(lines)
+    for i, p in enumerate(lines):
+        assert_equal(r.primitives[i], p)
 
 def test_region_bounds():
     """ Test region bounding box calculation
     """
-    points = ((0, 0), (1,0), (1,1), (0,1))
-    r = Region(points)
+    apt = Circle((0,0), 0)
+    lines = (Line((0,0), (1,0), apt), Line((1,0), (1,1), apt), Line((1,1), (0,1), apt), Line((0,1), (0,0), apt))
+    r = Region(lines)
     xbounds, ybounds = r.bounding_box
     assert_array_almost_equal(xbounds, (0, 1))
     assert_array_almost_equal(ybounds, (0, 1))
 
-def test_region_conversion():
-    points = ((2.54, 25.4), (254.0,2540.0), (25400.0,254000.0), (2.54,25.4))
-    r = Region(points, units='metric')
-    r.to_inch()
-    assert_equal(set(r.points), {(0.1, 1.0), (10.0, 100.0), (1000.0, 10000.0)})
-
-    points = ((0.1, 1.0), (10.0, 100.0), (1000.0, 10000.0), (0.1, 1.0))
-    r = Region(points, units='inch')
-    r.to_metric()
-    assert_equal(set(r.points), {(2.54, 25.4), (254.0, 2540.0), (25400.0, 254000.0)})
 
 def test_region_offset():
-    points = ((0, 0), (1,0), (1,1), (0,1))
-    r = Region(points)
-    r.offset(1, 0)
-    assert_equal(set(r.points), {(1, 0), (2, 0), (2,1), (1, 1)})
+    apt = Circle((0,0), 0)
+    lines = (Line((0,0), (1,0), apt), Line((1,0), (1,1), apt), Line((1,1), (0,1), apt), Line((0,1), (0,0), apt))
+    r = Region(lines)
+    xlim, ylim = r.bounding_box
     r.offset(0, 1)
-    assert_equal(set(r.points), {(1, 1), (2, 1), (2,2), (1, 2)})
+    assert_array_almost_equal((xlim, tuple([y+1 for y in ylim])), r.bounding_box)
 
 def test_round_butterfly_ctor():
     """ Test round butterfly creation