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 "include/gpu/gl/GrGLTypes.h"
12#include "include/private/GrTypesPriv.h"
13#include "include/private/SkTArray.h"
14#include "src/gpu/GrGpuResource.h"
15#include "src/gpu/gl/GrGLDefines.h"
16
17class GrBuffer;
18class GrGLGpu;
19
20/**
21 * This sets and tracks the vertex attribute array state. It is used internally by GrGLVertexArray
22 * (below) but is separate because it is also used to track the state of vertex array object 0.
23 */
24class GrGLAttribArrayState {
25public:
26 explicit GrGLAttribArrayState(int arrayCount = 0) {
27 this->resize(arrayCount);
28 }
29
30 void resize(int newCount) {
31 fAttribArrayStates.resize_back(newCount);
32 this->invalidate();
33 }
34
35 /**
36 * This function enables and sets vertex attrib state for the specified attrib index. It is
37 * assumed that the GrGLAttribArrayState is tracking the state of the currently bound vertex
38 * array object.
39 */
40 void set(GrGLGpu*,
41 int attribIndex,
42 const GrBuffer* vertexBuffer,
43 GrVertexAttribType cpuType,
44 GrSLType gpuType,
45 GrGLsizei stride,
46 size_t offsetInBytes,
47 int divisor = 0);
48
49 /**
50 * This function enables the first 'enabledCount' vertex arrays and disables the rest.
51 */
52 void enableVertexArrays(const GrGLGpu*, int enabledCount,
53 GrPrimitiveRestart = GrPrimitiveRestart::kNo);
54
55 void invalidate() {
56 int count = fAttribArrayStates.count();
57 for (int i = 0; i < count; ++i) {
58 fAttribArrayStates[i].invalidate();
59 }
60 fEnableStateIsValid = false;
61 }
62
63 /**
64 * The number of attrib arrays that this object is configured to track.
65 */
66 int count() const { return fAttribArrayStates.count(); }
67
68private:
69 static constexpr int kInvalidDivisor = -1;
70
71 /**
72 * Tracks the state of glVertexAttribArray for an attribute index.
73 */
74 struct AttribArrayState {
75 void invalidate() {
76 fVertexBufferUniqueID.makeInvalid();
77 fDivisor = kInvalidDivisor;
78 fUsingCpuBuffer = false;
79 }
80
81 GrGpuResource::UniqueID fVertexBufferUniqueID;
82 bool fUsingCpuBuffer;
83 GrVertexAttribType fCPUType;
84 GrSLType fGPUType;
85 GrGLsizei fStride;
86 const GrGLvoid* fOffset;
87 int fDivisor;
88 };
89
90 SkSTArray<16, AttribArrayState, true> fAttribArrayStates;
91 int fNumEnabledArrays;
92 GrPrimitiveRestart fPrimitiveRestartEnabled;
93 bool fEnableStateIsValid = false;
94};
95
96/**
97 * This class represents an OpenGL vertex array object. It manages the lifetime of the vertex array
98 * and is used to track the state of the vertex array to avoid redundant GL calls.
99 */
100class GrGLVertexArray {
101public:
102 GrGLVertexArray(GrGLint id, int attribCount);
103
104 /**
105 * Binds this vertex array. If the ID has been deleted or abandoned then nullptr is returned.
106 * Otherwise, the GrGLAttribArrayState that is tracking this vertex array's attrib bindings is
107 * returned.
108 */
109 GrGLAttribArrayState* bind(GrGLGpu*);
110
111 /**
112 * This is a version of the above function that also binds an index buffer to the vertex
113 * array object.
114 */
115 GrGLAttribArrayState* bindWithIndexBuffer(GrGLGpu* gpu, const GrBuffer* indexBuffer);
116
117 GrGLuint arrayID() const { return fID; }
118
119 void invalidateCachedState();
120
121private:
122 GrGLuint fID;
123 GrGLAttribArrayState fAttribArrays;
124 GrGpuResource::UniqueID fIndexBufferUniqueID;
125};
126
127#endif
128