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 GrGLVertexArray_DEFINED
9#define GrGLVertexArray_DEFINED
10
11#include "GrTypesPriv.h"
12#include "gl/GrGLDefines.h"
13#include "gl/GrGLFunctions.h"
14#include "SkTArray.h"
15
16class GrGLVertexBuffer;
17class GrGLIndexBuffer;
18class GrGLGpu;
19
20struct GrGLAttribLayout {
21    GrGLint     fCount;
22    GrGLenum    fType;
23    GrGLboolean fNormalized;
24};
25
26static inline const GrGLAttribLayout& GrGLAttribTypeToLayout(GrVertexAttribType type) {
27    SkASSERT(type >= 0 && type < kGrVertexAttribTypeCount);
28    static const GrGLAttribLayout kLayouts[kGrVertexAttribTypeCount] = {
29        {1, GR_GL_FLOAT, false},         // kFloat_GrVertexAttribType
30        {2, GR_GL_FLOAT, false},         // kVec2f_GrVertexAttribType
31        {3, GR_GL_FLOAT, false},         // kVec3f_GrVertexAttribType
32        {4, GR_GL_FLOAT, false},         // kVec4f_GrVertexAttribType
33        {1, GR_GL_UNSIGNED_BYTE, true},  // kUByte_GrVertexAttribType
34        {4, GR_GL_UNSIGNED_BYTE, true},  // kVec4ub_GrVertexAttribType
35        {2, GR_GL_SHORT, false},         // kVec2s_GrVertexAttribType
36    };
37    GR_STATIC_ASSERT(0 == kFloat_GrVertexAttribType);
38    GR_STATIC_ASSERT(1 == kVec2f_GrVertexAttribType);
39    GR_STATIC_ASSERT(2 == kVec3f_GrVertexAttribType);
40    GR_STATIC_ASSERT(3 == kVec4f_GrVertexAttribType);
41    GR_STATIC_ASSERT(4 == kUByte_GrVertexAttribType);
42    GR_STATIC_ASSERT(5 == kVec4ub_GrVertexAttribType);
43    GR_STATIC_ASSERT(6 == kVec2s_GrVertexAttribType);
44    GR_STATIC_ASSERT(SK_ARRAY_COUNT(kLayouts) == kGrVertexAttribTypeCount);
45    return kLayouts[type];
46}
47
48/**
49 * This sets and tracks the vertex attribute array state. It is used internally by GrGLVertexArray
50 * (below) but is separate because it is also used to track the state of vertex array object 0.
51 */
52class GrGLAttribArrayState {
53public:
54    explicit GrGLAttribArrayState(int arrayCount = 0) {
55        this->resize(arrayCount);
56    }
57
58    void resize(int newCount) {
59        fAttribArrayStates.resize_back(newCount);
60        for (int i = 0; i < newCount; ++i) {
61            fAttribArrayStates[i].invalidate();
62        }
63    }
64
65    /**
66     * This function enables and sets vertex attrib state for the specified attrib index. It is
67     * assumed that the GrGLAttribArrayState is tracking the state of the currently bound vertex
68     * array object.
69     */
70    void set(const GrGLGpu*,
71             int index,
72             GrGLVertexBuffer*,
73             GrGLint size,
74             GrGLenum type,
75             GrGLboolean normalized,
76             GrGLsizei stride,
77             GrGLvoid* offset);
78
79    /**
80     * This function disables vertex attribs not present in the mask. It is assumed that the
81     * GrGLAttribArrayState is tracking the state of the currently bound vertex array object.
82     */
83    void disableUnusedArrays(const GrGLGpu*, uint64_t usedAttribArrayMask);
84
85    void invalidate() {
86        int count = fAttribArrayStates.count();
87        for (int i = 0; i < count; ++i) {
88            fAttribArrayStates[i].invalidate();
89        }
90    }
91
92    void notifyVertexBufferDelete(GrGLuint id) {
93        int count = fAttribArrayStates.count();
94        for (int i = 0; i < count; ++i) {
95            if (fAttribArrayStates[i].fAttribPointerIsValid &&
96                id == fAttribArrayStates[i].fVertexBufferID) {
97                fAttribArrayStates[i].invalidate();
98            }
99        }
100    }
101
102    /**
103     * The number of attrib arrays that this object is configured to track.
104     */
105    int count() const { return fAttribArrayStates.count(); }
106
107private:
108    /**
109     * Tracks the state of glVertexAttribArray for an attribute index.
110     */
111    struct AttribArrayState {
112            void invalidate() {
113                fEnableIsValid = false;
114                fAttribPointerIsValid = false;
115            }
116
117            bool        fEnableIsValid;
118            bool        fAttribPointerIsValid;
119            bool        fEnabled;
120            GrGLuint    fVertexBufferID;
121            GrGLint     fSize;
122            GrGLenum    fType;
123            GrGLboolean fNormalized;
124            GrGLsizei   fStride;
125            GrGLvoid*   fOffset;
126    };
127
128    SkSTArray<16, AttribArrayState, true> fAttribArrayStates;
129};
130
131/**
132 * This class represents an OpenGL vertex array object. It manages the lifetime of the vertex array
133 * and is used to track the state of the vertex array to avoid redundant GL calls.
134 */
135class GrGLVertexArray {
136public:
137    GrGLVertexArray(GrGLint id, int attribCount);
138
139    /**
140     * Binds this vertex array. If the ID has been deleted or abandoned then NULL is returned.
141     * Otherwise, the GrGLAttribArrayState that is tracking this vertex array's attrib bindings is
142     * returned.
143     */
144    GrGLAttribArrayState* bind(GrGLGpu*);
145
146    /**
147     * This is a version of the above function that also binds an index buffer to the vertex
148     * array object.
149     */
150    GrGLAttribArrayState* bindWithIndexBuffer(GrGLGpu* gpu, const GrGLIndexBuffer*);
151
152    void notifyIndexBufferDelete(GrGLuint bufferID);
153
154    void notifyVertexBufferDelete(GrGLuint id) {
155        fAttribArrays.notifyVertexBufferDelete(id);
156    }
157
158    GrGLuint arrayID() const { return fID; }
159
160    void invalidateCachedState();
161
162private:
163    GrGLuint                fID;
164    GrGLAttribArrayState    fAttribArrays;
165    GrGLuint                fIndexBufferID;
166    bool                    fIndexBufferIDIsValid;
167};
168
169#endif
170