- added options for trace segmentation that can be useful for auto-levelling (code snippet from Lei Zheng from a rejected pull request on FlatCAM https://bitbucket.org/realthunder/ )

camlib.py

@@ -4332,6 +4332,8 @@ class CNCjob(Geometry):
                  spindlespeed=None, dwell=True, dwelltime=1000,
                  toolchangez=0.787402,
                  endz=2.0,
+                 segx=None,
+                 segy=None,
                  steps_per_circle=None):
 
         # Used when parsing G-code arcs
@@ -4376,6 +4378,9 @@ class CNCjob(Geometry):
         self.dwell = dwell
         self.dwelltime = dwelltime
 
+        self.segx = float(segx) if segx is not None else 0.0
+        self.segy = float(segy) if segy is not None else 0.0
+
         self.input_geometry_bounds = None
 
         # Attributes to be included in serialization
@@ -5456,6 +5461,61 @@ class CNCjob(Geometry):
         self.solid_geometry = cascaded_union([geo['geom'] for geo in self.gcode_parsed])
         return self.solid_geometry
 
+    # code snippet added by Lei Zheng in a rejected pull request on FlatCAM https://bitbucket.org/realthunder/
+    def segment(self, coords):
+        """
+        break long linear lines to make it more auto level friendly
+        """
+
+        if len(coords) < 2 or self.segx <= 0 and self.segy <= 0:
+            return list(coords)
+
+        path = [coords[0]]
+
+        # break the line in either x or y dimension only
+        def linebreak_single(line, dim, dmax):
+            if dmax <= 0:
+                return None
+
+            if line[1][dim] > line[0][dim]:
+                sign = 1.0
+                d = line[1][dim] - line[0][dim]
+            else:
+                sign = -1.0
+                d = line[0][dim] - line[1][dim]
+            if d > dmax:
+                # make sure we don't make any new lines too short
+                if d > dmax * 2:
+                    dd = dmax
+                else:
+                    dd = d / 2
+                other = dim ^ 1
+                return (line[0][dim] + dd * sign, line[0][other] + \
+                        dd * (line[1][other] - line[0][other]) / d)
+            return None
+
+        # recursively breaks down a given line until it is within the
+        # required step size
+        def linebreak(line):
+            pt_new = linebreak_single(line, 0, self.segx)
+            if pt_new is None:
+                pt_new2 = linebreak_single(line, 1, self.segy)
+            else:
+                pt_new2 = linebreak_single((line[0], pt_new), 1, self.segy)
+            if pt_new2 is not None:
+                pt_new = pt_new2[::-1]
+
+            if pt_new is None:
+                path.append(line[1])
+            else:
+                path.append(pt_new)
+                linebreak((pt_new, line[1]))
+
+        for pt in coords[1:]:
+            linebreak((path[-1], pt))
+
+        return path
+
     def linear2gcode(self, linear, tolerance=0, down=True, up=True,
                      z_cut=None, z_move=None, zdownrate=None,
                      feedrate=None, feedrate_z=None, feedrate_rapid=None, cont=False):
@@ -5500,7 +5560,9 @@ class CNCjob(Geometry):
 
         gcode = ""
 
-        path = list(target_linear.coords)
+        # path = list(target_linear.coords)
+        path = self.segment(target_linear.coords)
+
         p = self.pp_geometry
 
         # Move fast to 1st point