GrPathProcessor.h revision e3ababe44315452cd33b96a18ce316ede09ff3c3 
1/*
2 * Copyright 2013 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 GrPathProcessor_DEFINED
9#define GrPathProcessor_DEFINED
10
11#include "GrPrimitiveProcessor.h"
12
13struct PathBatchTracker {
14    GrGPInput fInputColorType;
15    GrGPInput fInputCoverageType;
16    GrColor fColor;
17    bool fUsesLocalCoords;
18};
19
20/*
21 * The path equivalent of the GP.  For now this just manages color. In the long term we plan on
22 * extending this class to handle all nvpr uniform / varying / program work.
23 */
24class GrPathProcessor : public GrPrimitiveProcessor {
25public:
26    static GrPathProcessor* Create(GrColor color,
27                                   const SkMatrix& viewMatrix = SkMatrix::I(),
28                                   const SkMatrix& localMatrix = SkMatrix::I()) {
29        return SkNEW_ARGS(GrPathProcessor, (color, viewMatrix, localMatrix));
30    }
31
32    void initBatchTracker(GrBatchTracker*, const GrPipelineInfo&) const override;
33
34    bool canMakeEqual(const GrBatchTracker& mine,
35                      const GrPrimitiveProcessor& that,
36                      const GrBatchTracker& theirs) const override;
37
38    const char* name() const override { return "PathProcessor"; }
39
40    GrColor color() const { return fColor; }
41    const SkMatrix& viewMatrix() const { return fViewMatrix; }
42    const SkMatrix& localMatrix() const { return fLocalMatrix; }
43
44
45    void getInvariantOutputColor(GrInitInvariantOutput* out) const override;
46    void getInvariantOutputCoverage(GrInitInvariantOutput* out) const override;
47
48    bool willUseGeoShader() const override { return false; }
49
50    virtual void getGLProcessorKey(const GrBatchTracker& bt,
51                                   const GrGLSLCaps& caps,
52                                   GrProcessorKeyBuilder* b) const override;
53
54    virtual GrGLPrimitiveProcessor* createGLInstance(const GrBatchTracker& bt,
55                                                     const GrGLSLCaps& caps) const override;
56
57private:
58    GrPathProcessor(GrColor color, const SkMatrix& viewMatrix, const SkMatrix& localMatrix);
59
60    /*
61     * CanCombineOutput will return true if two draws are 'batchable' from a color perspective.
62     * TODO is this really necessary?
63     */
64    static bool CanCombineOutput(GrGPInput left, GrColor lColor, GrGPInput right, GrColor rColor) {
65        if (left != right) {
66            return false;
67        }
68
69        if (kUniform_GrGPInput == left && lColor != rColor) {
70            return false;
71        }
72
73        return true;
74    }
75
76    static bool CanCombineLocalMatrices(const GrPrimitiveProcessor& l,
77                                        bool leftUsesLocalCoords,
78                                        const GrPrimitiveProcessor& r,
79                                        bool rightUsesLocalCoords) {
80        if (leftUsesLocalCoords != rightUsesLocalCoords) {
81            return false;
82        }
83
84        const GrPathProcessor& left = l.cast<GrPathProcessor>();
85        const GrPathProcessor& right = r.cast<GrPathProcessor>();
86        if (leftUsesLocalCoords && !left.localMatrix().cheapEqualTo(right.localMatrix())) {
87            return false;
88        }
89        return true;
90    }
91
92    bool hasExplicitLocalCoords() const override { return false; }
93
94    GrColor fColor;
95    const SkMatrix fViewMatrix;
96    const SkMatrix fLocalMatrix;
97
98    typedef GrPrimitiveProcessor INHERITED;
99};
100
101#endif
102