Path: Use _optimizeLinearSegments utility in _planarSinglePassProcess

Slightly clean up the code by separating linear segment optimization
from gcode generation. While the current optimization is not very
effective once there is any kind of meshing noise, having a single
method performing the optimization will make it easier to tweak
tolerances or strategies.

src/Mod/Path/PathScripts/PathSurface.py

@@ -1076,45 +1076,20 @@ class ObjectSurface(PathOp.ObjectOp):
 
         return GCODE
 
-    def _planarSinglepassProcess(self, obj, PNTS):
-        output = []
-        optimize = obj.OptimizeLinearPaths
-        lenPNTS = len(PNTS)
-        lop = None
-        onLine = False
-
-        # Initialize first three points
-        nxt = None
-        pnt = PNTS[0]
-        prev = FreeCAD.Vector(-442064564.6, 258539656553.27, 3538553425.847)
-
-        #  Add temp end point
-        PNTS.append(FreeCAD.Vector(-4895747464.6, -25855763553.2, 35865763425))
-
+    def _planarSinglepassProcess(self, obj, points):
+        if obj.OptimizeLinearPaths:
+            points = self._optimizeLinearSegments(points)
         # Begin processing ocl points list into gcode
-        for i in range(0, lenPNTS):
-            # Calculate next point for consideration with current point
-            nxt = PNTS[i + 1]
-
-            # Process point
-            if optimize:
-                if pnt.isOnLineSegment(prev, nxt):
-                    onLine = True
-                else:
-                    onLine = False
-                    output.append(Path.Command('G1', {'X': pnt.x, 'Y': pnt.y, 'Z': pnt.z, 'F': self.horizFeed}))
-            else:
-                output.append(Path.Command('G1', {'X': pnt.x, 'Y': pnt.y, 'Z': pnt.z, 'F': self.horizFeed}))
-
-            # Rotate point data
-            if onLine is False:
-                prev = pnt
-            pnt = nxt
-        # Efor
-
-        PNTS.pop()  # Remove temp end point
-
-        return output
+        commands = []
+        for pnt in points:
+            commands.append(
+                Path.Command('G1', {
+                    'X': pnt.x,
+                    'Y': pnt.y,
+                    'Z': pnt.z,
+                    'F': self.horizFeed
+                }))
+        return commands
 
     def _planarDropCutMulti(self, JOB, obj, pdc, safePDC, depthparams, SCANDATA):
         GCODE = [Path.Command('N (Beginning of Multi-pass layers.)', {})]