Add 'plugins/CuraEngineBackend/' from commit '918d4b41c8'

git-subtree-dir: plugins/CuraEngineBackend
git-subtree-mainline: 49210587ff
git-subtree-split: 918d4b41c8

plugins/CuraEngineBackend/LayerData.py

@@ -0,0 +1,90 @@
+from UM.Mesh.MeshData import MeshData
+from UM.Math.Color import Color
+
+import numpy
+import math
+
+class LayerData(MeshData):
+    def __init__(self):
+        super().__init__()
+        self._layers = {}
+        self._element_counts = {}
+
+    def addPolygon(self, layer, type, data):
+        if layer not in self._layers:
+            self._layers[layer] = []
+
+        p = Polygon(self, type, data)
+        self._layers[layer].append(p)
+
+    def getLayers(self):
+        return self._layers
+
+    def getElementCounts(self):
+        return self._element_counts
+
+    def build(self):
+        for layer, data in self._layers.items():
+            if layer not in self._element_counts:
+                self._element_counts[layer] = []
+
+            for polygon in data:
+                polygon.build()
+                self._element_counts[layer].append(polygon.elementCount)
+
+class Polygon():
+    NoneType = 0
+    Inset0Type = 1
+    InsetXType = 2
+    SkinType = 3
+    SupportType = 4
+    SkirtType = 5
+
+    def __init__(self, mesh, type, data):
+        super().__init__()
+        self._mesh = mesh
+        self._type = type
+        self._data = data
+
+    def build(self):
+        self._begin = self._mesh._vertex_count
+        self._mesh.addVertices(self._data)
+        self._end = self._begin + len(self._data) - 1
+
+        color = None
+        if self._type == self.Inset0Type:
+            color = [1, 0, 0, 1]
+        elif self._type == self.InsetXType:
+            color = [0, 1, 0, 1]
+        elif self._type == self.SkinType:
+            color = [1, 1, 0, 1]
+        elif self._type == self.SupportType:
+            color = [0, 1, 1, 1]
+        elif self._type == self.SkirtType:
+            color = [0, 1, 1, 1]
+        else:
+            color = [1, 1, 1, 1]
+
+        colors = [color for i in range(len(self._data))]
+        self._mesh.addColors(numpy.array(colors, dtype=numpy.float32))
+
+        indices = []
+        for i in range(self._begin, self._end):
+            indices.append(i)
+            indices.append(i + 1)
+
+        indices.append(self._end)
+        indices.append(self._begin)
+        self._mesh.addIndices(numpy.array(indices, dtype=numpy.int32))
+
+    @property
+    def type(self):
+        return self._type
+
+    @property
+    def data(self):
+        return self._data
+
+    @property
+    def elementCount(self):
+        return (self._end - self._begin) * 2 #The range of vertices multiplied by 2 since each vertex is used twice