Add many render tests based on the Umaco gerger specification. Fix multiple rendering bugs, especially related to holes in flashed apertures

42 files changed, 699 insertions, 48 deletions

diff --git a/gerber/cam.py b/gerber/cam.py
index 28918cb..f64aa34 100644
--- a/gerber/cam.py
+++ b/gerber/cam.py
@@ -260,7 +260,7 @@ class CamFile(object):
             If provided, save the rendered image to `filename`
         """
 
-        ctx.set_bounds(self.bounds)
+        ctx.set_bounds(self.bounding_box)
         ctx._paint_background()
 
         if invert:
diff --git a/gerber/gerber_statements.py b/gerber/gerber_statements.py
index 52e7ac3..3212c1c 100644
--- a/gerber/gerber_statements.py
+++ b/gerber/gerber_statements.py
@@ -279,9 +279,9 @@ class ADParamStmt(ParamStmt):
         return cls('AD', dcode, 'R', ([width, height],))
     
     @classmethod
-    def circle(cls, dcode, diameter):
+    def circle(cls, dcode, diameter, hole_diameter):
         '''Create a circular aperture definition statement'''
-        return cls('AD', dcode, 'C', ([diameter],))
+        return cls('AD', dcode, 'C', ([diameter, hole_diameter],))
     
     @classmethod
     def obround(cls, dcode, width, height):
diff --git a/gerber/primitives.py b/gerber/primitives.py
index 90b6fb9..b8ee344 100644
--- a/gerber/primitives.py
+++ b/gerber/primitives.py
@@ -370,12 +370,13 @@ class Arc(Primitive):
 class Circle(Primitive):

     """

     """

-    def __init__(self, position, diameter, **kwargs):

+    def __init__(self, position, diameter, hole_diameter = 0, **kwargs):

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

         validate_coordinates(position)

         self.position = position

         self.diameter = diameter

-        self._to_convert = ['position', 'diameter']

+        self.hole_diameter = hole_diameter

+        self._to_convert = ['position', 'diameter', 'hole_diameter']

 

     @property 

     def flashed(self):

@@ -384,6 +385,10 @@ class Circle(Primitive):
     @property

     def radius(self):

         return self.diameter / 2.

+    

+    @property

+    def hole_radius(self):

+        return self.hole_diameter / 2.

 

     @property

     def bounding_box(self):

@@ -402,7 +407,7 @@ class Circle(Primitive):
         if not isinstance(other, Circle):

             return False

         

-        if self.diameter != other.diameter:

+        if self.diameter != other.diameter or self.hole_diameter != other.hole_diameter:

             return False

         

         equiv_position = tuple(map(add, other.position, offset))

@@ -456,13 +461,14 @@ class Rectangle(Primitive):
     Only aperture macro generated Rectangle objects can be rotated. If you aren't in a AMGroup,

     then you don't need to worry about rotation

     """

-    def __init__(self, position, width, height, **kwargs):

+    def __init__(self, position, width, height, hole_diameter=0, **kwargs):

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

         validate_coordinates(position)

         self.position = position

         self.width = width

         self.height = height

-        self._to_convert = ['position', 'width', 'height']

+        self.hole_diameter = hole_diameter

+        self._to_convert = ['position', 'width', 'height', 'hole_diameter']

         

     @property 

     def flashed(self):

@@ -477,6 +483,11 @@ class Rectangle(Primitive):
     def upper_right(self):

         return (self.position[0] + (self._abs_width / 2.),

                 self.position[1] + (self._abs_height / 2.))

+        

+    @property

+    def hole_radius(self):

+        """The radius of the hole. If there is no hole, returns 0"""

+        return self.hole_diameter / 2.

 

     @property

     def bounding_box(self):

@@ -499,12 +510,12 @@ class Rectangle(Primitive):
                 math.sin(math.radians(self.rotation)) * self.width)

         

     def equivalent(self, other, offset):

-        '''Is this the same as the other rect, ignoring the offiset?'''

+        """Is this the same as the other rect, ignoring the offset?"""

 

         if not isinstance(other, Rectangle):

             return False

         

-        if self.width != other.width or self.height != other.height or self.rotation != other.rotation:

+        if self.width != other.width or self.height != other.height or self.rotation != other.rotation or self.hole_diameter != other.hole_diameter:

             return False

         

         equiv_position = tuple(map(add, other.position, offset))

@@ -655,13 +666,14 @@ class RoundRectangle(Primitive):
 class Obround(Primitive):

     """

     """

-    def __init__(self, position, width, height, **kwargs):

+    def __init__(self, position, width, height, hole_diameter=0, **kwargs):

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

         validate_coordinates(position)

         self.position = position

         self.width = width

         self.height = height

-        self._to_convert = ['position', 'width', 'height']

+        self.hole_diameter = hole_diameter

+        self._to_convert = ['position', 'width', 'height', 'hole_diameter']

         

     @property 

     def flashed(self):

@@ -676,6 +688,11 @@ class Obround(Primitive):
     def upper_right(self):

         return (self.position[0] + (self._abs_width / 2.),

                 self.position[1] + (self._abs_height / 2.))

+        

+    @property

+    def hole_radius(self):

+        """The radius of the hole. If there is no hole, returns 0"""

+        return self.hole_diameter / 2.

 

     @property

     def orientation(self):

diff --git a/gerber/render/cairo_backend.py b/gerber/render/cairo_backend.py
index 0cb230b..78ccf34 100644
--- a/gerber/render/cairo_backend.py
+++ b/gerber/render/cairo_backend.py
@@ -20,13 +20,14 @@ try:
 except ImportError:

     import cairocffi as cairo

     
-from operator import mul, div
 import math

+from operator import mul, div

 import tempfile

 

+from ..primitives import *

 from .render import GerberContext, RenderSettings

 from .theme import THEMES

-from ..primitives import *

+

 

 try:

     from cStringIO import StringIO

@@ -219,15 +220,30 @@ class GerberCairoContext(GerberContext):
         center = tuple(map(mul, circle.position, self.scale))

         if not self.invert:

             ctx = self.ctx

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

+            ctx.set_source_rgba(color[0], color[1], color[2], alpha=self.alpha)

             ctx.set_operator(cairo.OPERATOR_OVER if circle.level_polarity == "dark" else cairo.OPERATOR_CLEAR)

         else:

             ctx = self.mask_ctx

             ctx.set_source_rgba(0.0, 0.0, 0.0, 1.0)

             ctx.set_operator(cairo.OPERATOR_CLEAR)

+            

+        if circle.hole_diameter > 0:

+            ctx.push_group()

+

         ctx.set_line_width(0)

         ctx.arc(center[0], center[1], radius=circle.radius * self.scale[0], angle1=0, angle2=2 * math.pi)

-        ctx.fill()
+        ctx.fill()

+        

+        if circle.hole_diameter > 0:

+            # Render the center clear

+

+            ctx.set_source_rgba(color[0], color[1], color[2], self.alpha)

+            ctx.set_operator(cairo.OPERATOR_CLEAR)        

+            ctx.arc(center[0], center[1], radius=circle.hole_radius * self.scale[0], angle1=0, angle2=2 * math.pi)

+            ctx.fill()

+            

+            ctx.pop_group_to_source()

+            ctx.paint_with_alpha(1)
 

     def _render_rectangle(self, rectangle, color):

         ll = map(mul, rectangle.lower_left, self.scale)

@@ -253,48 +269,95 @@ class GerberCairoContext(GerberContext):
             ll[1] = ll[1] - center[1]

             matrix.rotate(rectangle.rotation)

             ctx.transform(matrix)

-     

+            

+        if rectangle.hole_diameter > 0:

+            ctx.push_group()

+

         ctx.set_line_width(0)

         ctx.rectangle(ll[0], ll[1], width, height)

         ctx.fill()

         

+        if rectangle.hole_diameter > 0:

+            # Render the center clear

+            ctx.set_source_rgba(color[0], color[1], color[2], self.alpha)

+            ctx.set_operator(cairo.OPERATOR_CLEAR)

+            center = map(mul, rectangle.position, self.scale)

+            ctx.arc(center[0], center[1], radius=rectangle.hole_radius * self.scale[0], angle1=0, angle2=2 * math.pi)

+            ctx.fill()

+            

+            ctx.pop_group_to_source()

+            ctx.paint_with_alpha(1)

+        

         if rectangle.rotation != 0:

             ctx.restore()
 

     def _render_obround(self, obround, color):

+        

+        if not self.invert:

+            ctx = self.ctx

+            ctx.set_source_rgba(color[0], color[1], color[2], alpha=self.alpha)

+            ctx.set_operator(cairo.OPERATOR_OVER if obround.level_polarity == "dark" else cairo.OPERATOR_CLEAR)

+        else:

+            ctx = self.mask_ctx

+            ctx.set_source_rgba(0.0, 0.0, 0.0, 1.0)

+            ctx.set_operator(cairo.OPERATOR_CLEAR)

+            

+        if obround.hole_diameter > 0:

+            ctx.push_group()

+

         self._render_circle(obround.subshapes['circle1'], color)

         self._render_circle(obround.subshapes['circle2'], color)

         self._render_rectangle(obround.subshapes['rectangle'], color)

         

+        if obround.hole_diameter > 0:

+            # Render the center clear

+            ctx.set_source_rgba(color[0], color[1], color[2], self.alpha)

+            ctx.set_operator(cairo.OPERATOR_CLEAR)

+            center = map(mul, obround.position, self.scale)

+            ctx.arc(center[0], center[1], radius=obround.hole_radius * self.scale[0], angle1=0, angle2=2 * math.pi)

+            ctx.fill()

+            

+            ctx.pop_group_to_source()

+            ctx.paint_with_alpha(1)

+

     def _render_polygon(self, polygon, color):

+        

+        # TODO Ths does not handle rotation of a polygon

+        if not self.invert:

+            ctx = self.ctx

+            ctx.set_source_rgba(color[0], color[1], color[2], alpha=self.alpha)

+            ctx.set_operator(cairo.OPERATOR_OVER if polygon.level_polarity == "dark" else cairo.OPERATOR_CLEAR)

+        else:

+            ctx = self.mask_ctx

+            ctx.set_source_rgba(0.0, 0.0, 0.0, 1.0)

+            ctx.set_operator(cairo.OPERATOR_CLEAR)

+            

         if polygon.hole_radius > 0:

-            self.ctx.push_group()

+            ctx.push_group()

         

         vertices = polygon.vertices 

-        

-        self.ctx.set_source_rgba(color[0], color[1], color[2], self.alpha)

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

-        self.ctx.set_line_width(0)

-        self.ctx.set_line_cap(cairo.LINE_CAP_ROUND)

+

+        ctx.set_line_width(0)

+        ctx.set_line_cap(cairo.LINE_CAP_ROUND)

         

         # Start from before the end so it is easy to iterate and make sure it is closed

-        self.ctx.move_to(*map(mul, vertices[-1], self.scale))

+        ctx.move_to(*map(mul, vertices[-1], self.scale))

         for v in vertices:

-            self.ctx.line_to(*map(mul, v, self.scale))

+            ctx.line_to(*map(mul, v, self.scale))

 

-        self.ctx.fill()

+        ctx.fill()

         

         if polygon.hole_radius > 0:

             # Render the center clear

             center = tuple(map(mul, polygon.position, self.scale))

-            self.ctx.set_source_rgba(color[0], color[1], color[2], self.alpha)

-            self.ctx.set_operator(cairo.OPERATOR_CLEAR)        

-            self.ctx.set_line_width(0)

-            self.ctx.arc(center[0], center[1], polygon.hole_radius * self.scale[0], 0, 2 * math.pi)

-            self.ctx.fill()

+            ctx.set_source_rgba(color[0], color[1], color[2], self.alpha)

+            ctx.set_operator(cairo.OPERATOR_CLEAR)        

+            ctx.set_line_width(0)

+            ctx.arc(center[0], center[1], polygon.hole_radius * self.scale[0], 0, 2 * math.pi)

+            ctx.fill()

             

-            self.ctx.pop_group_to_source()

-            self.ctx.paint_with_alpha(1)

+            ctx.pop_group_to_source()

+            ctx.paint_with_alpha(1)

 

     def _render_drill(self, circle, color):

         self._render_circle(circle, color)

diff --git a/gerber/render/rs274x_backend.py b/gerber/render/rs274x_backend.py
index 972edcb..15e9154 100644
--- a/gerber/render/rs274x_backend.py
+++ b/gerber/render/rs274x_backend.py
@@ -151,7 +151,7 @@ class Rs274xContext(GerberContext):
         # Select the right aperture if not already selected
         if aperture:
             if isinstance(aperture, Circle):
-                aper = self._get_circle(aperture.diameter)
+                aper = self._get_circle(aperture.diameter, aperture.hole_diameter)
             elif isinstance(aperture, Rectangle):
                 aper = self._get_rectangle(aperture.width, aperture.height)
             elif isinstance(aperture, Obround):
@@ -275,10 +275,10 @@ class Rs274xContext(GerberContext):
             
         self._pos = primitive.position
             
-    def _get_circle(self, diameter, dcode = None):
+    def _get_circle(self, diameter, hole_diameter, dcode = None):
         '''Define a circlar aperture'''
         
-        aper = self._circles.get(diameter, None)
+        aper = self._circles.get((diameter, hole_diameter), None)
 
         if not aper:
             if not dcode:
@@ -287,15 +287,15 @@ class Rs274xContext(GerberContext):
             else:
                 self._next_dcode = max(dcode + 1, self._next_dcode)
                 
-            aper = ADParamStmt.circle(dcode, diameter)
-            self._circles[diameter] = aper
+            aper = ADParamStmt.circle(dcode, diameter, hole_diameter)
+            self._circles[(diameter, hole_diameter)] = aper
             self.header.append(aper)
 
         return aper
         
     def _render_circle(self, circle, color):
 
-        aper = self._get_circle(circle.diameter)
+        aper = self._get_circle(circle.diameter, circle.hole_diameter)
         self._render_flash(circle, aper)
 
     def _get_rectangle(self, width, height, dcode = None):
diff --git a/gerber/rs274x.py b/gerber/rs274x.py
index 260fbf8..e88bba7 100644
--- a/gerber/rs274x.py
+++ b/gerber/rs274x.py
@@ -482,15 +482,33 @@ class GerberParser(object):
         aperture = None
         if shape == 'C':
             diameter = modifiers[0][0]
-            aperture = Circle(position=None, diameter=diameter, units=self.settings.units)
+            
+            if len(modifiers[0]) >= 2:
+                hole_diameter = modifiers[0][1]
+            else:
+                hole_diameter = 0
+                
+            aperture = Circle(position=None, diameter=diameter, hole_diameter=hole_diameter, units=self.settings.units)
         elif shape == 'R':
             width = modifiers[0][0]
             height = modifiers[0][1]
-            aperture = Rectangle(position=None, width=width, height=height, units=self.settings.units)
+            
+            if len(modifiers[0]) >= 3:
+                hole_diameter = modifiers[0][2]
+            else:
+                hole_diameter = 0
+                
+            aperture = Rectangle(position=None, width=width, height=height, hole_diameter=hole_diameter, units=self.settings.units)
         elif shape == 'O':
             width = modifiers[0][0]
             height = modifiers[0][1]
-            aperture = Obround(position=None, width=width, height=height, units=self.settings.units)
+            
+            if len(modifiers[0]) >= 3:
+                hole_diameter = modifiers[0][2]
+            else:
+                hole_diameter = 0
+                
+            aperture = Obround(position=None, width=width, height=height, hole_diameter=hole_diameter, units=self.settings.units)
         elif shape == 'P':
             outer_diameter = modifiers[0][0]
             number_vertices = int(modifiers[0][1])
diff --git a/gerber/tests/golden/example_coincident_hole.png b/gerber/tests/golden/example_coincident_hole.png
new file mode 100644
index 0000000..9855b11
--- /dev/null
+++ b/gerber/tests/golden/example_coincident_hole.png
diff --git a/gerber/tests/golden/example_cutin_multiple.png b/gerber/tests/golden/example_cutin_multiple.png
new file mode 100644
index 0000000..ebc1191
--- /dev/null
+++ b/gerber/tests/golden/example_cutin_multiple.png
diff --git a/gerber/tests/golden/example_flash_circle.png b/gerber/tests/golden/example_flash_circle.png
new file mode 100644
index 0000000..0c407f6
--- /dev/null
+++ b/gerber/tests/golden/example_flash_circle.png
diff --git a/gerber/tests/golden/example_flash_obround.png b/gerber/tests/golden/example_flash_obround.png
new file mode 100644
index 0000000..2fd4dc3
--- /dev/null
+++ b/gerber/tests/golden/example_flash_obround.png
diff --git a/gerber/tests/golden/example_flash_polygon.png b/gerber/tests/golden/example_flash_polygon.png
new file mode 100644
index 0000000..89a964b
--- /dev/null
+++ b/gerber/tests/golden/example_flash_polygon.png
diff --git a/gerber/tests/golden/example_flash_rectangle.png b/gerber/tests/golden/example_flash_rectangle.png
new file mode 100644
index 0000000..797e0c3
--- /dev/null
+++ b/gerber/tests/golden/example_flash_rectangle.png
diff --git a/gerber/tests/golden/example_fully_coincident.png b/gerber/tests/golden/example_fully_coincident.png
new file mode 100644
index 0000000..4e522ff
--- /dev/null
+++ b/gerber/tests/golden/example_fully_coincident.png
diff --git a/gerber/tests/golden/example_not_overlapping_contour.png b/gerber/tests/golden/example_not_overlapping_contour.png
new file mode 100644
index 0000000..4e522ff
--- /dev/null
+++ b/gerber/tests/golden/example_not_overlapping_contour.png
diff --git a/gerber/tests/golden/example_not_overlapping_touching.png b/gerber/tests/golden/example_not_overlapping_touching.png
new file mode 100644
index 0000000..d485495
--- /dev/null
+++ b/gerber/tests/golden/example_not_overlapping_touching.png
diff --git a/gerber/tests/golden/example_overlapping_contour.png b/gerber/tests/golden/example_overlapping_contour.png
new file mode 100644
index 0000000..7504311
--- /dev/null
+++ b/gerber/tests/golden/example_overlapping_contour.png
diff --git a/gerber/tests/golden/example_overlapping_touching.png b/gerber/tests/golden/example_overlapping_touching.png
new file mode 100644
index 0000000..7504311
--- /dev/null
+++ b/gerber/tests/golden/example_overlapping_touching.png
diff --git a/gerber/tests/golden/example_simple_contour.png b/gerber/tests/golden/example_simple_contour.png
new file mode 100644
index 0000000..564ae14
--- /dev/null
+++ b/gerber/tests/golden/example_simple_contour.png
diff --git a/gerber/tests/golden/example_single_contour.png b/gerber/tests/golden/example_single_contour.png
new file mode 100644
index 0000000..3341638
--- /dev/null
+++ b/gerber/tests/golden/example_single_contour.png
diff --git a/gerber/tests/golden/example_single_contour_3.png b/gerber/tests/golden/example_single_contour_3.png
new file mode 100644
index 0000000..1eecfee
--- /dev/null
+++ b/gerber/tests/golden/example_single_contour_3.png
diff --git a/gerber/tests/golden/example_single_quadrant.png b/gerber/tests/golden/example_single_quadrant.png
new file mode 100644
index 0000000..89b763f
--- /dev/null
+++ b/gerber/tests/golden/example_single_quadrant.png
diff --git a/gerber/tests/golden/example_two_square_boxes.png b/gerber/tests/golden/example_two_square_boxes.png
index 4732995..98d0518 100644
--- a/gerber/tests/golden/example_two_square_boxes.png
+++ b/gerber/tests/golden/example_two_square_boxes.png
diff --git a/gerber/tests/resources/example_coincident_hole.gbr b/gerber/tests/resources/example_coincident_hole.gbr
new file mode 100644
index 0000000..4f896ea
--- /dev/null
+++ b/gerber/tests/resources/example_coincident_hole.gbr
@@ -0,0 +1,24 @@
+G04 ex2: overlapping*
+%FSLAX24Y24*%
+%MOMM*%
+%SRX1Y1I0.000J0.000*%
+%ADD10C,1.00000*%
+G01*
+%LPD*%
+G36*
+X0Y50000D02*
+Y100000D01*
+X100000D01*
+Y0D01*
+X0D01*
+Y50000D01*
+G04 first fully coincident linear segment*
+X10000D01*
+X50000Y10000D01*
+X90000Y50000D01*
+X50000Y90000D01*
+X10000Y50000D01*
+G04 second fully coincident linear segment*
+X0D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_cutin.gbr b/gerber/tests/resources/example_cutin.gbr
new file mode 100644
index 0000000..365e5e1
--- /dev/null
+++ b/gerber/tests/resources/example_cutin.gbr
@@ -0,0 +1,18 @@
+G04 Umaco uut-in example*
+%FSLAX24Y24*%
+G75*
+G36*
+X20000Y100000D02*
+G01*
+X120000D01*
+Y20000D01*
+X20000D01*
+Y60000D01*
+X50000D01*
+G03*
+X50000Y60000I30000J0D01*
+G01*
+X20000D01*
+Y100000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_cutin_multiple.gbr b/gerber/tests/resources/example_cutin_multiple.gbr
new file mode 100644
index 0000000..8e19429
--- /dev/null
+++ b/gerber/tests/resources/example_cutin_multiple.gbr
@@ -0,0 +1,28 @@
+G04 multiple cutins*
+%FSLAX24Y24*%
+%MOMM*%
+%SRX1Y1I0.000J0.000*%
+%ADD10C,1.00000*%
+%LPD*%
+G36*
+X1220000Y2570000D02*
+G01*
+Y2720000D01*
+X1310000D01*
+Y2570000D01*
+X1250000D01*
+Y2600000D01*
+X1290000D01*
+Y2640000D01*
+X1250000D01*
+Y2670000D01*
+X1290000D01*
+Y2700000D01*
+X1250000D01*
+Y2670000D01*
+Y2640000D01*
+Y2600000D01*
+Y2570000D01*
+X1220000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_flash_circle.gbr b/gerber/tests/resources/example_flash_circle.gbr
new file mode 100644
index 0000000..20b2566
--- /dev/null
+++ b/gerber/tests/resources/example_flash_circle.gbr
@@ -0,0 +1,10 @@
+G04 Flashes of circular apertures*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10C,0.5*%
+%ADD11C,0.5X0.25*%
+D10*
+X000000Y000000D03*
+D11*
+X010000D03*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_flash_obround.gbr b/gerber/tests/resources/example_flash_obround.gbr
new file mode 100644
index 0000000..5313f82
--- /dev/null
+++ b/gerber/tests/resources/example_flash_obround.gbr
@@ -0,0 +1,10 @@
+G04 Flashes of rectangular apertures*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10O,0.46X0.26*%
+%ADD11O,0.46X0.26X0.19*%
+D10*
+X000000Y000000D03*
+D11*
+X010000D03*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_flash_polygon.gbr b/gerber/tests/resources/example_flash_polygon.gbr
new file mode 100644
index 0000000..177cf9b
--- /dev/null
+++ b/gerber/tests/resources/example_flash_polygon.gbr
@@ -0,0 +1,10 @@
+G04 Flashes of rectangular apertures*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10P,.40X6*%
+%ADD11P,.40X6X0.0X0.19*%
+D10*
+X000000Y000000D03*
+D11*
+X010000D03*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_flash_rectangle.gbr b/gerber/tests/resources/example_flash_rectangle.gbr
new file mode 100644
index 0000000..8fde812
--- /dev/null
+++ b/gerber/tests/resources/example_flash_rectangle.gbr
@@ -0,0 +1,10 @@
+G04 Flashes of rectangular apertures*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10R,0.44X0.25*%
+%ADD11R,0.44X0.25X0.19*%
+D10*
+X000000Y000000D03*
+D11*
+X010000D03*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_fully_coincident.gbr b/gerber/tests/resources/example_fully_coincident.gbr
new file mode 100644
index 0000000..3764128
--- /dev/null
+++ b/gerber/tests/resources/example_fully_coincident.gbr
@@ -0,0 +1,23 @@
+G04 ex1: non overlapping*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10C,1.00000*%
+G01*
+%LPD*%
+G36*
+X0Y50000D02*
+Y100000D01*
+X100000D01*
+Y0D01*
+X0D01*
+Y50000D01*
+G04 first fully coincident linear segment*
+X-10000D01*
+X-50000Y10000D01*
+X-90000Y50000D01*
+X-50000Y90000D01*
+X-10000Y50000D01*
+G04 second fully coincident linear segment*
+X0D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_level_holes.gbr b/gerber/tests/resources/example_level_holes.gbr
new file mode 100644
index 0000000..1b4e189
--- /dev/null
+++ b/gerber/tests/resources/example_level_holes.gbr
@@ -0,0 +1,39 @@
+G04 This file illustrates how to use levels to create holes*
+%FSLAX25Y25*%
+%MOMM*%
+G01*
+G04 First level: big square - dark polarity*
+%LPD*%
+G36*
+X250000Y250000D02*
+X1750000D01*
+Y1750000D01*
+X250000D01*
+Y250000D01*
+G37*
+G04 Second level: big circle - clear polarity*
+%LPC*%
+G36*
+G75*
+X500000Y1000000D02*
+G03*
+X500000Y1000000I500000J0D01*
+G37*
+G04 Third level: small square - dark polarity*
+%LPD*%
+G36*
+X750000Y750000D02*
+X1250000D01*
+Y1250000D01*
+X750000D01*
+Y750000D01*
+G37*
+G04 Fourth level: small circle - clear polarity*
+%LPC*%
+G36*
+G75*
+X1150000Y1000000D02*
+G03*
+X1150000Y1000000I250000J0D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_not_overlapping_contour.gbr b/gerber/tests/resources/example_not_overlapping_contour.gbr
new file mode 100644
index 0000000..e3ea631
--- /dev/null
+++ b/gerber/tests/resources/example_not_overlapping_contour.gbr
@@ -0,0 +1,20 @@
+G04 Non-overlapping contours*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10C,1.00000*%
+G01*
+%LPD*%
+G36*
+X0Y50000D02*
+Y100000D01*
+X100000D01*
+Y0D01*
+X0D01*
+Y50000D01*
+X-10000D02*
+X-50000Y10000D01*
+X-90000Y50000D01*
+X-50000Y90000D01*
+X-10000Y50000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_not_overlapping_touching.gbr b/gerber/tests/resources/example_not_overlapping_touching.gbr
new file mode 100644
index 0000000..3b9b955
--- /dev/null
+++ b/gerber/tests/resources/example_not_overlapping_touching.gbr
@@ -0,0 +1,20 @@
+G04 Non-overlapping and touching*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10C,1.00000*%
+G01*
+%LPD*%
+G36*
+X0Y50000D02*
+Y100000D01*
+X100000D01*
+Y0D01*
+X0D01*
+Y50000D01*
+D02*
+X-50000Y10000D01*
+X-90000Y50000D01*
+X-50000Y90000D01*
+X0Y50000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_overlapping_contour.gbr b/gerber/tests/resources/example_overlapping_contour.gbr
new file mode 100644
index 0000000..74886a2
--- /dev/null
+++ b/gerber/tests/resources/example_overlapping_contour.gbr
@@ -0,0 +1,20 @@
+G04 Overlapping contours*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10C,1.00000*%
+G01*
+%LPD*%
+G36*
+X0Y50000D02*
+Y100000D01*
+X100000D01*
+Y0D01*
+X0D01*
+Y50000D01*
+X10000D02*
+X50000Y10000D01*
+X90000Y50000D01*
+X50000Y90000D01*
+X10000Y50000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_overlapping_touching.gbr b/gerber/tests/resources/example_overlapping_touching.gbr
new file mode 100644
index 0000000..27fce15
--- /dev/null
+++ b/gerber/tests/resources/example_overlapping_touching.gbr
@@ -0,0 +1,20 @@
+G04 Overlapping and touching*
+%FSLAX24Y24*%
+%MOMM*%
+%ADD10C,1.00000*%
+G01*
+%LPD*%
+G36*
+X0Y50000D02*
+Y100000D01*
+X100000D01*
+Y0D01*
+X0D01*
+Y50000D01*
+D02*
+X50000Y10000D01*
+X90000Y50000D01*
+X50000Y90000D01*
+X0Y50000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_simple_contour.gbr b/gerber/tests/resources/example_simple_contour.gbr
new file mode 100644
index 0000000..d851760
--- /dev/null
+++ b/gerber/tests/resources/example_simple_contour.gbr
@@ -0,0 +1,16 @@
+G04 Ucamco ex. 4.6.4: Simple contour*
+%FSLAX25Y25*%
+%MOIN*%
+%ADD10C,0.010*%
+G36*
+X200000Y300000D02*
+G01*
+X700000D01*
+Y100000D01*
+X1100000Y500000D01*
+X700000Y900000D01*
+Y700000D01*
+X200000D01*
+Y300000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_single_contour_1.gbr b/gerber/tests/resources/example_single_contour_1.gbr
new file mode 100644
index 0000000..e9f9a75
--- /dev/null
+++ b/gerber/tests/resources/example_single_contour_1.gbr
@@ -0,0 +1,15 @@
+G04 Ucamco ex. 4.6.5: Single contour #1*
+%FSLAX25Y25*%
+%MOMM*%
+%ADD11C,0.01*%
+G01*
+D11*
+X3000Y5000D01*
+G36*
+X50000Y50000D02*
+X60000D01*
+Y60000D01*
+X50000D01*
+Y50000Y50000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_single_contour_2.gbr b/gerber/tests/resources/example_single_contour_2.gbr
new file mode 100644
index 0000000..085c72c
--- /dev/null
+++ b/gerber/tests/resources/example_single_contour_2.gbr
@@ -0,0 +1,15 @@
+G04 Ucamco ex. 4.6.5: Single contour #2*
+%FSLAX25Y25*%
+%MOMM*%
+%ADD11C,0.01*%
+G01*
+D11*
+X3000Y5000D01*
+X50000Y50000D02*
+G36*
+X60000D01*
+Y60000D01*
+X50000D01*
+Y50000Y50000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_single_contour_3.gbr b/gerber/tests/resources/example_single_contour_3.gbr
new file mode 100644
index 0000000..40de149
--- /dev/null
+++ b/gerber/tests/resources/example_single_contour_3.gbr
@@ -0,0 +1,15 @@
+G04 Ucamco ex. 4.6.5: Single contour #2*
+%FSLAX25Y25*%
+%MOMM*%
+%ADD11C,0.01*%
+G01*
+D11*
+X3000Y5000D01*
+X50000Y50000D01*
+G36*
+X60000D01*
+Y60000D01*
+X50000D01*
+Y50000Y50000D01*
+G37*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/resources/example_single_quadrant.gbr b/gerber/tests/resources/example_single_quadrant.gbr
new file mode 100644
index 0000000..c398601
--- /dev/null
+++ b/gerber/tests/resources/example_single_quadrant.gbr
@@ -0,0 +1,18 @@
+G04 Ucamco ex. 4.5.8: Single quadrant*
+%FSLAX23Y23*%
+%MOIN*%
+%ADD10C,0.010*%
+G74*
+D10*
+X1100Y600D02*
+G03*
+X700Y1000I400J0D01*
+X300Y600I0J400D01*
+X700Y200I400J0D01*
+X1100Y600I0J400D01*
+X300D02*
+G01*
+X1100D01*
+X700Y200D02*
+Y1000D01*
+M02*
\ No newline at end of file
diff --git a/gerber/tests/test_cairo_backend.py b/gerber/tests/test_cairo_backend.py
index e298439..38cffba 100644
--- a/gerber/tests/test_cairo_backend.py
+++ b/gerber/tests/test_cairo_backend.py
@@ -8,16 +8,125 @@ import os
 from ..render.cairo_backend import GerberCairoContext
 from ..rs274x import read, GerberFile
 from .tests import *
+from nose.tools import assert_tuple_equal
 
+def test_render_two_boxes():
+    """Umaco exapmle of two boxes"""
+    _test_render('resources/example_two_square_boxes.gbr', 'golden/example_two_square_boxes.png')
 
-TWO_BOXES_FILE = os.path.join(os.path.dirname(__file__),
-                                'resources/example_two_square_boxes.gbr')
-TWO_BOXES_EXPECTED = os.path.join(os.path.dirname(__file__),
-                                'golden/example_two_square_boxes.png')
 
-def test_render_polygon():
+def test_render_single_quadrant():
+    """Umaco exapmle of a single quadrant arc"""
+    _test_render('resources/example_single_quadrant.gbr', 'golden/example_single_quadrant.png')
+
+
+def test_render_simple_contour():
+    """Umaco exapmle of a simple arrow-shaped contour"""
+    gerber = _test_render('resources/example_simple_contour.gbr', 'golden/example_simple_contour.png')
+    
+    # Check the resulting dimensions
+    assert_tuple_equal(((2.0, 11.0), (1.0, 9.0)), gerber.bounding_box)
+
+    
+def test_render_single_contour_1():
+    """Umaco example of a single contour
+    
+    The resulting image for this test is used by other tests because they must generate the same output."""
+    _test_render('resources/example_single_contour_1.gbr', 'golden/example_single_contour.png')
+
+
+def test_render_single_contour_2():
+    """Umaco exapmle of a single contour, alternate contour end order
+    
+    The resulting image for this test is used by other tests because they must generate the same output."""
+    _test_render('resources/example_single_contour_2.gbr', 'golden/example_single_contour.png')
+
+
+def test_render_single_contour_3():
+    """Umaco exapmle of a single contour with extra line"""
+    _test_render('resources/example_single_contour_3.gbr', 'golden/example_single_contour_3.png')
+    
+    
+def test_render_not_overlapping_contour():
+    """Umaco example of D02 staring a second contour"""
+    _test_render('resources/example_not_overlapping_contour.gbr', 'golden/example_not_overlapping_contour.png')
+    
+
+def test_render_not_overlapping_touching():
+    """Umaco example of D02 staring a second contour"""
+    _test_render('resources/example_not_overlapping_touching.gbr', 'golden/example_not_overlapping_touching.png')
+
+
+def test_render_overlapping_touching():
+    """Umaco example of D02 staring a second contour"""
+    _test_render('resources/example_overlapping_touching.gbr', 'golden/example_overlapping_touching.png')
+
+
+def test_render_overlapping_contour():
+    """Umaco example of D02 staring a second contour"""
+    _test_render('resources/example_overlapping_contour.gbr', 'golden/example_overlapping_contour.png')
+
+
+def _DISABLED_test_render_level_holes():
+    """Umaco example of using multiple levels to create multiple holes"""
+    
+    # TODO This is clearly rendering wrong. I'm temporarily checking this in because there are more
+    # rendering fixes in the related repository that may resolve these.
+    _test_render('resources/example_level_holes.gbr', 'golden/example_overlapping_contour.png')
+
+
+def _DISABLED_test_render_cutin():
+    """Umaco example of using a cutin"""
+
+    # TODO This is clearly rendering wrong.
+    _test_render('resources/example_cutin.gbr', 'golden/example_cutin.png')
+
+
+def test_render_fully_coincident():
+    """Umaco example of coincident lines rendering two contours"""
+
+    _test_render('resources/example_fully_coincident.gbr', 'golden/example_fully_coincident.png')
+
+
+def test_render_coincident_hole():
+    """Umaco example of coincident lines rendering a hole in the contour"""
+
+    _test_render('resources/example_coincident_hole.gbr', 'golden/example_coincident_hole.png')
+
+
+def test_render_cutin_multiple():
+    """Umaco example of a region with multiple cutins"""
+
+    _test_render('resources/example_cutin_multiple.gbr', 'golden/example_cutin_multiple.png')
+    
+
+def test_flash_circle():
+    """Umaco example a simple circular flash with and without a hole"""
+
+    _test_render('resources/example_flash_circle.gbr', 'golden/example_flash_circle.png')
+
+
+def test_flash_rectangle():
+    """Umaco example a simple rectangular flash with and without a hole"""
+
+    _test_render('resources/example_flash_rectangle.gbr', 'golden/example_flash_rectangle.png')
+
+
+def test_flash_obround():
+    """Umaco example a simple obround flash with and without a hole"""
+
+    _test_render('resources/example_flash_obround.gbr', 'golden/example_flash_obround.png')
+
+
+def test_flash_polygon():
+    """Umaco example a simple polygon flash with and without a hole"""
+
+    _test_render('resources/example_flash_polygon.gbr', 'golden/example_flash_polygon.png', 'golden/example_flash_polygon.png')
+
+def _resolve_path(path):
+    return os.path.join(os.path.dirname(__file__),
+                                path)
 
-    _test_render(TWO_BOXES_FILE, TWO_BOXES_EXPECTED)
 
 def _test_render(gerber_path, png_expected_path, create_output_path = None):
     """Render the gerber file and compare to the expected PNG output.
@@ -33,6 +142,11 @@ def _test_render(gerber_path, png_expected_path, create_output_path = None):
         This is primarily to help with 
     """
     
+    gerber_path = _resolve_path(gerber_path)
+    png_expected_path = _resolve_path(png_expected_path)
+    if create_output_path:
+        create_output_path = _resolve_path(create_output_path)
+    
     gerber = read(gerber_path)
 
     # Create PNG image to the memory stream
@@ -56,3 +170,5 @@ def _test_render(gerber_path, png_expected_path, create_output_path = None):
         expected_bytes = expected_file.read()
     
     assert_equal(expected_bytes, actual_bytes)
+    
+    return gerber
diff --git a/gerber/tests/test_primitives.py b/gerber/tests/test_primitives.py
index a88497c..bc67891 100644
--- a/gerber/tests/test_primitives.py
+++ b/gerber/tests/test_primitives.py
@@ -236,6 +236,12 @@ def test_circle_radius():
     c = Circle((1, 1), 2)
     assert_equal(c.radius, 1)
 
+def test_circle_hole_radius():
+    """ Test Circle primitive hole radius calculation
+    """
+    c = Circle((1, 1), 4, 2)
+    assert_equal(c.hole_radius, 1)
+
 def test_circle_bounds():
     """ Test Circle bounding box calculation
     """
@@ -243,35 +249,81 @@ def test_circle_bounds():
     assert_equal(c.bounding_box, ((0, 2), (0, 2)))
 
 def test_circle_conversion():
+    """Circle conversion of units"""
+    # Circle initially metric, no hole
     c = Circle((2.54, 25.4), 254.0, units='metric')
 
     c.to_metric()   #shouldn't do antyhing
     assert_equal(c.position, (2.54, 25.4))
     assert_equal(c.diameter, 254.)
+    assert_equal(c.hole_diameter, 0.)
 
     c.to_inch()
     assert_equal(c.position, (0.1, 1.))
     assert_equal(c.diameter, 10.)
+    assert_equal(c.hole_diameter, 0)
 
     #no effect
     c.to_inch()
     assert_equal(c.position, (0.1, 1.))
     assert_equal(c.diameter, 10.)
+    assert_equal(c.hole_diameter, 0)
+    
+    # Circle initially metric, with hole
+    c = Circle((2.54, 25.4), 254.0, 127.0, units='metric')
 
+    c.to_metric()   #shouldn't do antyhing
+    assert_equal(c.position, (2.54, 25.4))
+    assert_equal(c.diameter, 254.)
+    assert_equal(c.hole_diameter, 127.)
+
+    c.to_inch()
+    assert_equal(c.position, (0.1, 1.))
+    assert_equal(c.diameter, 10.)
+    assert_equal(c.hole_diameter, 5.)
+
+    #no effect
+    c.to_inch()
+    assert_equal(c.position, (0.1, 1.))
+    assert_equal(c.diameter, 10.)
+    assert_equal(c.hole_diameter, 5.)
+    
+    # Circle initially inch, no hole
     c = Circle((0.1, 1.0), 10.0, units='inch')
     #No effect
     c.to_inch()
     assert_equal(c.position, (0.1, 1.))
     assert_equal(c.diameter, 10.)
+    assert_equal(c.hole_diameter, 0)
 
     c.to_metric()
     assert_equal(c.position, (2.54, 25.4))
     assert_equal(c.diameter, 254.)
+    assert_equal(c.hole_diameter, 0)
 
     #no effect
     c.to_metric()
     assert_equal(c.position, (2.54, 25.4))
     assert_equal(c.diameter, 254.)
+    assert_equal(c.hole_diameter, 0)
+
+    c = Circle((0.1, 1.0), 10.0, 5.0, units='inch')
+    #No effect
+    c.to_inch()
+    assert_equal(c.position, (0.1, 1.))
+    assert_equal(c.diameter, 10.)
+    assert_equal(c.hole_diameter, 5.)
+
+    c.to_metric()
+    assert_equal(c.position, (2.54, 25.4))
+    assert_equal(c.diameter, 254.)
+    assert_equal(c.hole_diameter, 127.)
+
+    #no effect
+    c.to_metric()
+    assert_equal(c.position, (2.54, 25.4))
+    assert_equal(c.diameter, 254.)
+    assert_equal(c.hole_diameter, 127.)
 
 def test_circle_offset():
     c = Circle((0, 0), 1)
@@ -355,6 +407,15 @@ def test_rectangle_ctor():
         assert_equal(r.position, pos)
         assert_equal(r.width, width)
         assert_equal(r.height, height)
+        
+def test_rectangle_hole_radius():
+    """ Test rectangle hole diameter calculation
+    """
+    r = Rectangle((0,0), 2, 2)
+    assert_equal(0, r.hole_radius)
+    
+    r = Rectangle((0,0), 2, 2, 1)
+    assert_equal(0.5, r.hole_radius)
 
 def test_rectangle_bounds():
     """ Test rectangle bounding box calculation
@@ -369,6 +430,9 @@ def test_rectangle_bounds():
     assert_array_almost_equal(ybounds, (-math.sqrt(2), math.sqrt(2)))
 
 def test_rectangle_conversion():
+    """Test converting rectangles between units"""
+    
+    # Initially metric no hole
     r = Rectangle((2.54, 25.4), 254.0, 2540.0, units='metric')
 
     r.to_metric()
@@ -385,7 +449,29 @@ def test_rectangle_conversion():
     assert_equal(r.position, (0.1, 1.0))
     assert_equal(r.width, 10.0)
     assert_equal(r.height, 100.0)
+    
+    # Initially metric with hole
+    r = Rectangle((2.54, 25.4), 254.0, 2540.0, 127.0, units='metric')
+
+    r.to_metric()
+    assert_equal(r.position, (2.54,25.4))
+    assert_equal(r.width, 254.0)
+    assert_equal(r.height, 2540.0)
+    assert_equal(r.hole_diameter, 127.0)
+
+    r.to_inch()
+    assert_equal(r.position, (0.1, 1.0))
+    assert_equal(r.width, 10.0)
+    assert_equal(r.height, 100.0)
+    assert_equal(r.hole_diameter, 5.0)
+
+    r.to_inch()
+    assert_equal(r.position, (0.1, 1.0))
+    assert_equal(r.width, 10.0)
+    assert_equal(r.height, 100.0)
+    assert_equal(r.hole_diameter, 5.0)
 
+    # Initially inch, no hole
     r = Rectangle((0.1, 1.0), 10.0, 100.0, units='inch')
     r.to_inch()
     assert_equal(r.position, (0.1, 1.0))
@@ -401,6 +487,26 @@ def test_rectangle_conversion():
     assert_equal(r.position, (2.54,25.4))
     assert_equal(r.width, 254.0)
     assert_equal(r.height, 2540.0)
+    
+    # Initially inch with hole
+    r = Rectangle((0.1, 1.0), 10.0, 100.0, 5.0, units='inch')
+    r.to_inch()
+    assert_equal(r.position, (0.1, 1.0))
+    assert_equal(r.width, 10.0)
+    assert_equal(r.height, 100.0)
+    assert_equal(r.hole_diameter, 5.0)
+
+    r.to_metric()
+    assert_equal(r.position, (2.54,25.4))
+    assert_equal(r.width, 254.0)
+    assert_equal(r.height, 2540.0)
+    assert_equal(r.hole_diameter, 127.0)
+
+    r.to_metric()
+    assert_equal(r.position, (2.54,25.4))
+    assert_equal(r.width, 254.0)
+    assert_equal(r.height, 2540.0)
+    assert_equal(r.hole_diameter, 127.0)
 
 def test_rectangle_offset():
     r = Rectangle((0, 0), 1, 2)