fixed GCode generation for automatically distributed support bridges in "corner" mode

fixed a small glitch for zero-sized polygons (corner distribution of support bridges)


git-svn-id: https://pycam.svn.sourceforge.net/svnroot/pycam/trunk@966 bbaffbd6-741e-11dd-a85d-61de82d9cad9

src/pycam/Gui/Settings.py

@@ -582,7 +582,6 @@ class ToolpathSettings:
             "average_distance": float,
             "minimum_bridges": int,
             "length": float,
-            "start_at_corner": bool,
         },
         "Program": {
             "unit": str,
@@ -662,13 +661,15 @@ class ToolpathSettings:
 
     def set_support_distributed(self, average_distance, minimum_bridges,
             thickness, height, length, start_at_corner=False):
-        self.support_grid["type"] = "distributed"
+        if start_at_corner:
+            self.support_grid["type"] = "distributed_corners"
+        else:
+            self.support_grid["type"] = "distributed_edges"
         self.support_grid["average_distance"] = average_distance
         self.support_grid["minimum_bridges"] = minimum_bridges
         self.support_grid["thickness"] = thickness
         self.support_grid["height"] = height
         self.support_grid["length"] = length
-        self.support_grid["start_at_corner"] = start_at_corner
 
     def get_support_grid(self):
         result = {}

src/pycam/Toolpath/Generator.py

@@ -180,7 +180,7 @@ def generate_toolpath(model, tool_settings=None,
                 adjustments_x=support_grid_adjustments_x,
                 adjustments_y=support_grid_adjustments_y)
         trimesh_models.append(support_grid_model)
-    elif (support_grid_type == "distributed") \
+    elif (support_grid_type in ("distributed_edges", "distributed_corners")) \
             and (not support_grid_average_distance is None) \
             and (not support_grid_thickness is None) \
             and (not support_grid_length is None):
@@ -204,10 +204,12 @@ def generate_toolpath(model, tool_settings=None,
             model = contour_model
         else:
             model = trimesh_models[0]
+        start_at_corners = (support_grid_type == "distributed_corners")
         support_grid_model = pycam.Toolpath.SupportGrid.get_support_distributed(
                 model, minz, support_grid_average_distance,
                 support_grid_minimum_bridges, support_grid_thickness,
-                support_grid_height, support_grid_length)
+                support_grid_height, support_grid_length,
+                start_at_corners=start_at_corners)
         trimesh_models.append(support_grid_model)
     elif (not support_grid_type) or (support_grid_type == "none"):
         pass

src/pycam/Toolpath/SupportGrid.py

@@ -221,6 +221,9 @@ def _get_corner_bridges(polygon, z_plane, min_bridges, average_distance, avoid_d
         - directions pointing away from the center of the polygon are preferred
     """
     center = polygon.get_barycenter()
+    if center is None:
+        # polygon is open or zero-sized
+        return []
     points = polygon.get_points()
     lines = polygon.get_lines()
     poly_lengths = polygon.get_lengths()