1 files changed, 89 insertions, 9 deletions

diff --git a/gerber/render/excellon_backend.py b/gerber/render/excellon_backend.py
index eb79f1b..b2c213f 100644
--- a/gerber/render/excellon_backend.py
+++ b/gerber/render/excellon_backend.py
@@ -1,21 +1,29 @@
 
 from .render import GerberContext
+from ..excellon import DrillSlot
 from ..excellon_statements import *
 
 class ExcellonContext(GerberContext):
     
+    MODE_DRILL = 1
+    MODE_SLOT =2 
+    
     def __init__(self, settings):
         GerberContext.__init__(self)
+        
+        # Statements that we write
         self.comments = []
         self.header = []
         self.tool_def = []
         self.body_start = [RewindStopStmt()]
         self.body = []
         self.start = [HeaderBeginStmt()]
-        self.end = [EndOfProgramStmt()]
         
+        # 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
@@ -33,9 +41,22 @@ class ExcellonContext(GerberContext):
         # 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.end
+        return self.start + self.comments + self.header + self.body_start + self.body + self._get_end()
         
     def set_bounds(self, bounds):
         pass
@@ -71,6 +92,9 @@ class ExcellonContext(GerberContext):
 
     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)
@@ -84,20 +108,76 @@ class ExcellonContext(GerberContext):
         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
             
-        # Slots don't use simplified points
-        self._pos = slot.end
-        self.body.append(SlotStmt.from_points(slot.start, slot.end))
+            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_down = 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