1 /*
2  * Copyright 2015 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #ifndef GrTessellator_DEFINED
9 #define GrTessellator_DEFINED
10 
11 #include "GrColor.h"
12 #include "SkPoint.h"
13 
14 class SkPath;
15 struct SkRect;
16 
17 /**
18  * Provides utility functions for converting paths to a collection of triangles.
19  */
20 
21 #define TESSELLATOR_WIREFRAME 0
22 
23 namespace GrTessellator {
24 
25 class VertexAllocator {
26 public:
VertexAllocator(size_t stride)27     VertexAllocator(size_t stride) : fStride(stride) {}
~VertexAllocator()28     virtual ~VertexAllocator() {}
29     virtual void* lock(int vertexCount) = 0;
30     virtual void unlock(int actualCount) = 0;
stride()31     size_t stride() const { return fStride; }
32 private:
33     size_t fStride;
34 };
35 
36 struct WindingVertex {
37     SkPoint fPos;
38     int fWinding;
39 };
40 
41 // Triangulates a path to an array of vertices. Each triangle is represented as a set of three
42 // WindingVertex entries, each of which contains the position and winding count (which is the same
43 // for all three vertices of a triangle). The 'verts' out parameter is set to point to the resultant
44 // vertex array. CALLER IS RESPONSIBLE for deleting this buffer to avoid a memory leak!
45 int PathToVertices(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds,
46                    WindingVertex** verts);
47 
48 int PathToTriangles(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds,
49                     VertexAllocator*, bool antialias, const GrColor& color,
50                     bool canTweakAlphaForCoverage, bool *isLinear);
51 }
52 
53 #endif
54