Fix hard requirement of cairo per #83, and add stubs for required subclass methods to GerberContext per #84

1 files changed, 45 insertions, 46 deletions

diff --git a/gerber/render/excellon_backend.py b/gerber/render/excellon_backend.py
index da5b22b..765d68c 100644
--- a/gerber/render/excellon_backend.py
+++ b/gerber/render/excellon_backend.py
@@ -4,13 +4,13 @@ from ..excellon import DrillSlot
 from ..excellon_statements import *
 
 class ExcellonContext(GerberContext):
-    
+
     MODE_DRILL = 1
-    MODE_SLOT =2 
-    
+    MODE_SLOT =2
+
     def __init__(self, settings):
         GerberContext.__init__(self)
-        
+
         # Statements that we write
         self.comments = []
         self.header = []
@@ -18,57 +18,57 @@ class ExcellonContext(GerberContext):
         self.body_start = [RewindStopStmt()]
         self.body = []
         self.start = [HeaderBeginStmt()]
-        
+
         # Current tool and position
         self.handled_tools = set()
         self.cur_tool = None
         self.drill_mode = ExcellonContext.MODE_DRILL
         self.drill_down = False
         self._pos = (None, None)
-        
+
         self.settings = settings
 
         self._start_header()
         self._start_comments()
-        
+
     def _start_header(self):
         """Create the header from the settings"""
-        
+
         self.header.append(UnitStmt.from_settings(self.settings))
-        
+
         if self.settings.notation == 'incremental':
             raise NotImplementedError('Incremental mode is not implemented')
         else:
             self.body.append(AbsoluteModeStmt())
-        
+
     def _start_comments(self):
-        
+
         # Write the digits used - this isn't valid Excellon statement, so we write as a comment
         self.comments.append(CommentStmt('FILE_FORMAT=%d:%d' % (self.settings.format[0], self.settings.format[1])))
-        
+
     def _get_end(self):
         """How we end depends on our mode"""
-        
+
         end = []
-        
+
         if self.drill_down:
             end.append(RetractWithClampingStmt())
             end.append(RetractWithoutClampingStmt())
-            
+
         end.append(EndOfProgramStmt())
-        
+
         return end
-        
+
     @property
     def statements(self):
         return self.start + self.comments + self.header + self.body_start + self.body + self._get_end()
-        
-    def set_bounds(self, bounds):
+
+    def set_bounds(self, bounds, *args, **kwargs):
         pass
-    
-    def _paint_background(self):
+
+    def paint_background(self):
         pass
-        
+
     def _render_line(self, line, color):
         raise ValueError('Invalid Excellon object')
     def _render_arc(self, arc, color):
@@ -76,7 +76,7 @@ class ExcellonContext(GerberContext):
 
     def _render_region(self, region, color):
         raise ValueError('Invalid Excellon object')
-        
+
     def _render_level_polarity(self, region):
         raise ValueError('Invalid Excellon object')
 
@@ -85,105 +85,104 @@ class ExcellonContext(GerberContext):
 
     def _render_rectangle(self, rectangle, color):
         raise ValueError('Invalid Excellon object')
-        
+
     def _render_obround(self, obround, color):
         raise ValueError('Invalid Excellon object')
-        
+
     def _render_polygon(self, polygon, color):
         raise ValueError('Invalid Excellon object')
-    
+
     def _simplify_point(self, point):
         return (point[0] if point[0] != self._pos[0] else None, point[1] if point[1] != self._pos[1] else None)
 
     def _render_drill(self, drill, color):
-        
+
         if self.drill_mode != ExcellonContext.MODE_DRILL:
             self._start_drill_mode()
-        
+
         tool = drill.hit.tool
         if not tool in self.handled_tools:
             self.handled_tools.add(tool)
             self.header.append(ExcellonTool.from_tool(tool))
-    
+
         if tool != self.cur_tool:
             self.body.append(ToolSelectionStmt(tool.number))
             self.cur_tool = tool
-            
+
         point = self._simplify_point(drill.position)
         self._pos = drill.position
         self.body.append(CoordinateStmt.from_point(point))
-        
+
     def _start_drill_mode(self):
         """
         If we are not in drill mode, then end the ROUT so we can do basic drilling
         """
-        
+
         if self.drill_mode == ExcellonContext.MODE_SLOT:
-            
+
             # Make sure we are retracted before changing modes
             last_cmd = self.body[-1]
             if self.drill_down:
                 self.body.append(RetractWithClampingStmt())
                 self.body.append(RetractWithoutClampingStmt())
                 self.drill_down = False
-            
+
             # Switch to drill mode
             self.body.append(DrillModeStmt())
             self.drill_mode = ExcellonContext.MODE_DRILL
-            
+
         else:
             raise ValueError('Should be in slot mode')
-        
+
     def _render_slot(self, slot, color):
-        
+
         # Set the tool first, before we might go into drill mode
         tool = slot.hit.tool
         if not tool in self.handled_tools:
             self.handled_tools.add(tool)
             self.header.append(ExcellonTool.from_tool(tool))
-            
+
         if tool != self.cur_tool:
             self.body.append(ToolSelectionStmt(tool.number))
             self.cur_tool = tool
-        
+
         # Two types of drilling - normal drill and slots
         if slot.hit.slot_type == DrillSlot.TYPE_ROUT:
 
             # For ROUT, setting the mode is part of the actual command.
-            
+
             # Are we in the right position?
             if slot.start != self._pos:
                 if self.drill_down:
                     # We need to move into the right position, so retract
                     self.body.append(RetractWithClampingStmt())
                     self.drill_down = False
-                    
+
                 # Move to the right spot
                 point = self._simplify_point(slot.start)
                 self._pos = slot.start
                 self.body.append(CoordinateStmt.from_point(point, mode="ROUT"))
-                
+
             # Now we are in the right spot, so drill down
             if not self.drill_down:
                 self.body.append(ZAxisRoutPositionStmt())
                 self.drill_down = True
-                
+
             # Do a linear move from our current position to the end position
             point = self._simplify_point(slot.end)
             self._pos = slot.end
             self.body.append(CoordinateStmt.from_point(point, mode="LINEAR"))
 
             self.drill_mode = ExcellonContext.MODE_SLOT
-                
+
         else:
             # This is a G85 slot, so do this in normally drilling mode
             if self.drill_mode != ExcellonContext.MODE_DRILL:
                 self._start_drill_mode()
-        
+
             # Slots don't use simplified points
             self._pos = slot.end
             self.body.append(SlotStmt.from_points(slot.start, slot.end))
 
     def _render_inverted_layer(self):
         pass
-        
\ No newline at end of file