| 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 GrTriangulator_DEFINED |
| 9 | #define GrTriangulator_DEFINED |
| 10 | |
| 11 | #include "include/core/SkPoint.h" |
| 12 | #include "include/private/SkColorData.h" |
| 13 | #include "src/gpu/GrColor.h" |
| 14 | |
| 15 | class GrEagerVertexAllocator; |
| 16 | class SkPath; |
| 17 | struct SkRect; |
| 18 | |
| 19 | /** |
| 20 | * Provides utility functions for converting paths to a collection of triangles. |
| 21 | */ |
| 22 | |
| 23 | #define TRIANGULATOR_WIREFRAME 0 |
| 24 | |
| 25 | namespace GrTriangulator { |
| 26 | |
| 27 | struct WindingVertex { |
| 28 | SkPoint fPos; |
| 29 | int fWinding; |
| 30 | }; |
| 31 | |
| 32 | // Triangulates a path to an array of vertices. Each triangle is represented as a set of three |
| 33 | // WindingVertex entries, each of which contains the position and winding count (which is the same |
| 34 | // for all three vertices of a triangle). The 'verts' out parameter is set to point to the resultant |
| 35 | // vertex array. CALLER IS RESPONSIBLE for deleting this buffer to avoid a memory leak! |
| 36 | int PathToVertices(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds, |
| 37 | WindingVertex** verts); |
| 38 | |
| 39 | enum class Mode { |
| 40 | kNormal, |
| 41 | |
| 42 | // Surround path edges with coverage ramps for antialiasing. |
| 43 | kEdgeAntialias, |
| 44 | |
| 45 | // Triangulate only each contour's inner polygon. The inner polygons connect the endpoints of |
| 46 | // each verb. (i.e., they are the path that would result from collapsing all curves to single |
| 47 | // lines.) |
| 48 | // |
| 49 | // If the inner polygons are not simple (e.g., self intersection, double winding), then the |
| 50 | // tessellator aborts and returns 0. |
| 51 | kSimpleInnerPolygons |
| 52 | }; |
| 53 | |
| 54 | constexpr size_t GetVertexStride(Mode mode) { |
| 55 | return sizeof(SkPoint) + ((Mode::kEdgeAntialias == mode) ? sizeof(float) : 0); |
| 56 | } |
| 57 | |
| 58 | int PathToTriangles(const SkPath& path, SkScalar tolerance, const SkRect& clipBounds, |
| 59 | GrEagerVertexAllocator*, Mode, bool *isLinear); |
| 60 | } |
| 61 | |
| 62 | #endif |
| 63 | |