1/*
2 * Copyright 2012 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 GrGLUniformManager_DEFINED
9#define GrGLUniformManager_DEFINED
10
11#include "gl/GrGLShaderVar.h"
12#include "gl/GrGLSL.h"
13#include "GrAllocator.h"
14
15#include "SkTArray.h"
16
17class GrGpuGL;
18class SkMatrix;
19
20/** Manages a program's uniforms.
21*/
22class GrGLUniformManager : public SkRefCnt {
23public:
24    // Opaque handle to a uniform
25    class UniformHandle {
26    public:
27        static UniformHandle CreateFromUniformIndex(int i);
28
29        bool isValid() const { return 0 != fValue; }
30
31        bool operator==(const UniformHandle& other) const { return other.fValue == fValue; }
32
33        UniformHandle()
34            : fValue(0) {
35        }
36
37    private:
38        UniformHandle(int value)
39            : fValue(~value) {
40            SkASSERT(isValid());
41        }
42
43        int toUniformIndex() const { SkASSERT(isValid()); return ~fValue; }
44
45        int fValue;
46        friend class GrGLUniformManager; // For accessing toUniformIndex().
47    };
48
49    GrGLUniformManager(GrGpuGL* gpu);
50
51    UniformHandle appendUniform(GrSLType type, int arrayCount = GrGLShaderVar::kNonArray);
52
53    /** Functions for uploading uniform values. The varities ending in v can be used to upload to an
54     *  array of uniforms. arrayCount must be <= the array count of the uniform.
55     */
56    void setSampler(UniformHandle, GrGLint texUnit) const;
57    void set1f(UniformHandle, GrGLfloat v0) const;
58    void set1fv(UniformHandle, int arrayCount, const GrGLfloat v[]) const;
59    void set2f(UniformHandle, GrGLfloat, GrGLfloat) const;
60    void set2fv(UniformHandle, int arrayCount, const GrGLfloat v[]) const;
61    void set3f(UniformHandle, GrGLfloat, GrGLfloat, GrGLfloat) const;
62    void set3fv(UniformHandle, int arrayCount, const GrGLfloat v[]) const;
63    void set4f(UniformHandle, GrGLfloat, GrGLfloat, GrGLfloat, GrGLfloat) const;
64    void set4fv(UniformHandle, int arrayCount, const GrGLfloat v[]) const;
65    // matrices are column-major, the first three upload a single matrix, the latter three upload
66    // arrayCount matrices into a uniform array.
67    void setMatrix3f(UniformHandle, const GrGLfloat matrix[]) const;
68    void setMatrix4f(UniformHandle, const GrGLfloat matrix[]) const;
69    void setMatrix3fv(UniformHandle, int arrayCount, const GrGLfloat matrices[]) const;
70    void setMatrix4fv(UniformHandle, int arrayCount, const GrGLfloat matrices[]) const;
71
72    // convenience method for uploading a SkMatrix to a 3x3 matrix uniform
73    void setSkMatrix(UniformHandle, const SkMatrix&) const;
74
75    struct BuilderUniform {
76        GrGLShaderVar fVariable;
77        uint32_t      fVisibility;
78    };
79    // This uses an allocator rather than array so that the GrGLShaderVars don't move in memory
80    // after they are inserted. Users of GrGLShaderBuilder get refs to the vars and ptrs to their
81    // name strings. Otherwise, we'd have to hand out copies.
82    typedef GrTAllocator<BuilderUniform> BuilderUniformArray;
83
84    /**
85     * Called by the GrGLShaderBuilder to know if the manager is using
86     * BindUniformLocation. In that case getUniformLocations must be called
87     * before the program is linked.
88     */
89    bool isUsingBindUniform() const { return fUsingBindUniform; }
90
91    /**
92     * Called by the GrGLShaderBuilder to get GL locations for all uniforms.
93     */
94    void getUniformLocations(GrGLuint programID, const BuilderUniformArray& uniforms);
95
96    /**
97     * Called by the GrGLShaderBuilder to access the array by the handle (index).
98     */
99    const BuilderUniform& getBuilderUniform(const BuilderUniformArray&, GrGLUniformManager::UniformHandle) const;
100
101private:
102    enum {
103        kUnusedUniform = -1,
104    };
105
106    struct Uniform {
107        GrGLint     fVSLocation;
108        GrGLint     fFSLocation;
109        GrSLType    fType;
110        int         fArrayCount;
111    };
112
113    bool fUsingBindUniform;
114    SkTArray<Uniform, true> fUniforms;
115    GrGpuGL* fGpu;
116
117    typedef SkRefCnt INHERITED;
118};
119
120#endif
121