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39
40#include "glbuffer_p.h"
41#include <graphicscontext_p.h>
42
43#if !defined(GL_UNIFORM_BUFFER)
44#define GL_UNIFORM_BUFFER 0x8A11
45#endif
46#if !defined(GL_ARRAY_BUFFER)
47#define GL_ARRAY_BUFFER 0x8892
48#endif
49#if !defined(GL_ELEMENT_ARRAY_BUFFER)
50#define GL_ELEMENT_ARRAY_BUFFER 0x8893
51#endif
52#if !defined(GL_SHADER_STORAGE_BUFFER)
53#define GL_SHADER_STORAGE_BUFFER 0x90D2
54#endif
55#if !defined(GL_PIXEL_PACK_BUFFER)
56#define GL_PIXEL_PACK_BUFFER 0x88EB
57#endif
58#if !defined(GL_PIXEL_UNPACK_BUFFER)
59#define GL_PIXEL_UNPACK_BUFFER 0x88EC
60#endif
61#if !defined(GL_DRAW_INDIRECT_BUFFER)
62#define GL_DRAW_INDIRECT_BUFFER 0x8F3F
63#endif
64
65QT_BEGIN_NAMESPACE
66
67namespace Qt3DRender {
68
69namespace Render {
70
71namespace OpenGL {
72
73// A UBO is created for each ShaderData Shader Pair
74// That means a UBO is unique to a shader/shaderdata
75
76namespace {
77
78GLenum glBufferTypes[] = {
79 GL_ARRAY_BUFFER,
80 GL_UNIFORM_BUFFER,
81 GL_ELEMENT_ARRAY_BUFFER,
82 GL_SHADER_STORAGE_BUFFER,
83 GL_PIXEL_PACK_BUFFER,
84 GL_PIXEL_UNPACK_BUFFER,
85 GL_DRAW_INDIRECT_BUFFER
86};
87
88} // anonymous
89
90GLBuffer::GLBuffer()
91 : m_bufferId(0)
92 , m_isCreated(false)
93 , m_bound(false)
94 , m_lastTarget(GL_ARRAY_BUFFER)
95{
96}
97
98bool GLBuffer::bind(GraphicsContext *ctx, Type t)
99{
100 if (m_bufferId == 0)
101 return false;
102 m_lastTarget = glBufferTypes[t];
103 ctx->openGLContext()->functions()->glBindBuffer(target: m_lastTarget, buffer: m_bufferId);
104 m_bound = true;
105 return true;
106}
107
108bool GLBuffer::release(GraphicsContext *ctx)
109{
110 m_bound = false;
111 ctx->openGLContext()->functions()->glBindBuffer(target: m_lastTarget, buffer: 0);
112 return true;
113}
114
115bool GLBuffer::create(GraphicsContext *ctx)
116{
117 ctx->openGLContext()->functions()->glGenBuffers(n: 1, buffers: &m_bufferId);
118 m_isCreated = true;
119 return m_bufferId != 0;
120}
121
122void GLBuffer::destroy(GraphicsContext *ctx)
123{
124 ctx->openGLContext()->functions()->glDeleteBuffers(n: 1, buffers: &m_bufferId);
125 m_isCreated = false;
126}
127
128void GLBuffer::allocate(GraphicsContext *ctx, uint size, bool dynamic)
129{
130 // Either GL_STATIC_DRAW OR GL_DYNAMIC_DRAW depending on the use case
131 // TO DO: find a way to know how a buffer/QShaderData will be used to use the right usage
132 ctx->openGLContext()->functions()->glBufferData(target: m_lastTarget, size, NULL, usage: dynamic ? GL_DYNAMIC_DRAW : GL_STATIC_DRAW);
133}
134
135void GLBuffer::allocate(GraphicsContext *ctx, const void *data, uint size, bool dynamic)
136{
137 ctx->openGLContext()->functions()->glBufferData(target: m_lastTarget, size, data, usage: dynamic ? GL_DYNAMIC_DRAW : GL_STATIC_DRAW);
138}
139
140void GLBuffer::update(GraphicsContext *ctx, const void *data, uint size, int offset)
141{
142 ctx->openGLContext()->functions()->glBufferSubData(target: m_lastTarget, offset, size, data);
143}
144
145QByteArray GLBuffer::download(GraphicsContext *ctx, uint size)
146{
147 char *gpu_ptr = ctx->mapBuffer(target: m_lastTarget, size);
148 QByteArray data;
149 if (gpu_ptr != nullptr) {
150 data.resize(size);
151 std::copy(first: gpu_ptr, last: gpu_ptr+size, result: data.data());
152 }
153 ctx->unmapBuffer(target: m_lastTarget);
154 return data;
155}
156
157void GLBuffer::bindBufferBase(GraphicsContext *ctx, int bindingPoint, GLBuffer::Type t)
158{
159 ctx->bindBufferBase(target: glBufferTypes[t], bindingIndex: bindingPoint, buffer: m_bufferId);
160}
161
162void GLBuffer::bindBufferBase(GraphicsContext *ctx, int bindingPoint)
163{
164 ctx->bindBufferBase(target: m_lastTarget, bindingIndex: bindingPoint, buffer: m_bufferId);
165}
166
167} // namespace OpenGL
168
169} // namespace Render
170
171} // namespace Qt3DRender
172
173QT_END_NAMESPACE
174

source code of qt3d/src/plugins/renderers/opengl/io/glbuffer.cpp