1 #include "graphicsbuffer.h"
6 static GLenum BufferUsageToGLUsage(GraphicsBuffer::BufferUsage buffer_usage)
11 case GraphicsBuffer::BufferUsageStaticDraw:
12 usage = GL_STATIC_DRAW;
14 case GraphicsBuffer::BufferUsageStaticRead:
15 usage = GL_STATIC_READ;
17 case GraphicsBuffer::BufferUsageStaticCopy:
18 usage = GL_STATIC_COPY;
20 case GraphicsBuffer::BufferUsageDynamicDraw:
21 usage = GL_DYNAMIC_DRAW;
23 case GraphicsBuffer::BufferUsageDynamicRead:
24 usage = GL_DYNAMIC_READ;
26 case GraphicsBuffer::BufferUsageDynamicCopy:
27 usage = GL_DYNAMIC_COPY;
29 case GraphicsBuffer::BufferUsageStreamDraw:
30 usage = GL_STREAM_DRAW;
32 case GraphicsBuffer::BufferUsageStreamRead:
33 usage = GL_STREAM_READ;
35 case GraphicsBuffer::BufferUsageStreamCopy:
36 usage = GL_STREAM_COPY;
39 SDL_assert(false && "Unknown buffer usage type."); //WTF?
40 usage = GL_DYNAMIC_DRAW;
45 static GLenum BufferTypeToGLType(GraphicsBuffer::BufferType buffer_type)
49 case GraphicsBuffer::BufferTypeVertex:
50 return GL_ARRAY_BUFFER;
51 case GraphicsBuffer::BufferTypeIndex:
52 return GL_ELEMENT_ARRAY_BUFFER;
53 case GraphicsBuffer::BufferTypePixelPack:
54 return GL_PIXEL_PACK_BUFFER;
55 case GraphicsBuffer::BufferTypePixelUnpack:
56 return GL_PIXEL_UNPACK_BUFFER;
57 case GraphicsBuffer::BufferTypeUniform:
58 return GL_UNIFORM_BUFFER;
59 case GraphicsBuffer::BufferTypeDrawIndirect:
60 return GL_DRAW_INDIRECT_BUFFER;
62 return GL_COPY_READ_BUFFER;
66 GraphicsBuffer::GraphicsBuffer()
71 m_buffer_shape_dirty = true;
73 m_buffer_usage = BufferUsageDynamicDraw;
75 SetUsage(BufferUsageStaticDraw);
78 GraphicsBuffer::~GraphicsBuffer()
84 glDeleteBuffers(1, &m_buffer_handle);
87 void GraphicsBuffer::SetType(GraphicsBuffer::BufferType bufType)
89 m_buffer_type = bufType;
92 void GraphicsBuffer::SetUsage(GraphicsBuffer::BufferUsage bufUsage)
94 if (bufUsage != m_buffer_usage)
96 m_buffer_usage = bufUsage;
97 m_buffer_shape_dirty = true;
101 void GraphicsBuffer::Invalidate()
103 m_invalidated = true;
104 if (!m_buffer_shape_dirty)
106 // Orphan the block of memory we're pointing to.
107 Upload(m_buffer_size, NULL);
109 // Apparently not supported.
110 //glInvalidateBufferData(m_buffer_handle);
113 bool GraphicsBuffer::RecreateBuffer(const void *data)
115 // If the buffer is not dirty, don't recreate it.
116 if (!m_buffer_shape_dirty) return false;
117 // If the buffer is mapped, don't recreate it.
118 if (!m_faking_map && m_map_pointer) return false;
119 // If the buffer has data in it we need, don't recreate it.
120 if (!m_invalidated) return false;
123 glDeleteBuffers(1, &m_buffer_handle);
125 glGenBuffers(1, &m_buffer_handle);
126 m_buffer_shape_dirty = false;
128 Upload(m_buffer_size, data);
132 void* GraphicsBuffer::Map(bool read, bool write, bool invalidate)
134 GLbitfield access = ((read)?GL_MAP_READ_BIT:0) | ((write)?GL_MAP_WRITE_BIT:0) | ((invalidate)?GL_MAP_INVALIDATE_BUFFER_BIT:0);
135 GLenum target = BufferTypeToGLType(m_buffer_type);
139 m_invalidated = true;
141 // Intel's Mesa driver does not rename the buffer when we map with GL_MAP_INVALIDATE_BUFFER_BIT,
142 // resulting in the CPU stalling waiting for rendering from the buffer to complete on the GPU.
143 // We manually force the buffer to be renamed here to avoid this.
144 m_buffer_shape_dirty = true;
148 Warn("Tried to map already mapped buffer!");
151 if (!read && m_buffer_usage == BufferUsage::BufferUsageStaticDraw)
153 m_map_pointer = malloc(m_buffer_size);
155 return m_map_pointer;
162 m_map_pointer = glMapBufferRange(target, 0, m_buffer_size, access);
164 return m_map_pointer;
167 void* GraphicsBuffer::MapRange(int offset, int length, bool read, bool write, bool invalidate)
169 GLbitfield access = ((read)?GL_MAP_READ_BIT:0) | ((write)?GL_MAP_WRITE_BIT:0) | ((invalidate)?GL_MAP_INVALIDATE_RANGE_BIT:0);
170 GLenum target = BufferTypeToGLType(m_buffer_type);
173 Warn("Tried to map already mapped buffer!");
179 m_map_pointer = glMapBufferRange(target, offset, length, access);
180 return m_map_pointer;
183 void GraphicsBuffer::UnMap()
185 GLenum target = BufferTypeToGLType(m_buffer_type);
189 Upload(m_buffer_size, m_map_pointer);
191 m_map_pointer = nullptr;
192 m_invalidated = false;
193 m_faking_map = false;
198 glUnmapBuffer(target);
199 m_map_pointer = nullptr;
200 m_invalidated = false;
203 void GraphicsBuffer::Upload(size_t length, const void* data)
205 GLenum target = BufferTypeToGLType(m_buffer_type);
207 GLenum usage = BufferUsageToGLUsage(m_buffer_usage);
209 m_invalidated = true;
210 m_buffer_size = length;
211 if (!RecreateBuffer(data))
214 glBufferData(target, length, data, usage);
217 m_invalidated = false;
220 void GraphicsBuffer::UploadRange(size_t length, intptr_t offset, const void* data)
222 GLenum target = BufferTypeToGLType(m_buffer_type);
227 glBufferSubData(target, offset, length, data);
228 m_invalidated = false;
231 void GraphicsBuffer::Resize(size_t length)
235 m_buffer_size = length;
239 // Create a new buffer and copy the old data into it.
241 GLuint old_buffer = m_buffer_handle;
242 glGenBuffers(1, &m_buffer_handle);
243 Upload(length, nullptr);
244 glBindBuffer(GL_COPY_READ_BUFFER, old_buffer);
245 glBindBuffer(GL_COPY_WRITE_BUFFER, m_buffer_handle);
246 glCopyBufferSubData(GL_COPY_READ_BUFFER, GL_COPY_WRITE_BUFFER, 0, 0, m_buffer_size);
247 glDeleteBuffers(1, &old_buffer);
248 m_buffer_size = length;
252 void GraphicsBuffer::Bind() const
254 if (m_buffer_type == BufferTypeUniform)
255 glBindBufferBase(GL_UNIFORM_BUFFER, 0, m_buffer_handle);
257 glBindBuffer(BufferTypeToGLType(m_buffer_type), m_buffer_handle);