Changing the message used from the engine from Layer to LayerOptimized.

plugins/CuraEngineBackend/Cura.proto

@@ -44,11 +44,40 @@ message Layer {
 }
 
 message Polygon {
-    bytes line_type = 1;
-    bytes points = 2;
-    bytes line_width = 3;
+    enum Type {
+        NoneType = 0;
+        Inset0Type = 1;
+        InsetXType = 2;
+        SkinType = 3;
+        SupportType = 4;
+        SkirtType = 5;
+        InfillType = 6;
+        SupportInfillType = 7;
+        MoveCombingType = 8;
+        MoveRetractionType = 9;
+    }
+    Type type = 1; // Type of move
+    bytes points = 2; // The points of the polygon, or two points if only a line segment (Currently only line segments are used)
+    float line_width = 3; // The width of the line being laid down
 }
 
+message LayerOptimized { 
+    int32 id = 1;
+    float height = 2; // Z position
+    float thickness = 3; // height of a single layer
+
+    repeated PathSegment path_segment = 4; // layer data
+}
+
+
+message PathSegment {
+	int32 ordinal = 1; // The absolute ordinal of this line segment
+    bytes line_type = 2; // Type of line segment as an unsigned char array of length 1 or N, where N is the number of line segments in this path
+    bytes points = 3; // The points defining the line segments, bytes of int64[2]? array of length N+1
+    bytes line_width = 4; // The widths of the line segments as bytes of a float?/int32? array of length 1 or N
+}
+
+
 message GCodeLayer {
     bytes data = 2;
 }
@@ -74,4 +103,4 @@ message GCodePrefix {
 }
 
 message SlicingFinished {
-}
+}