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::BufferTypeTexture:
60 return GL_TEXTURE_BUFFER;
61 case GraphicsBuffer::BufferTypeDrawIndirect:
62 return GL_DRAW_INDIRECT_BUFFER;
64 return GL_COPY_READ_BUFFER;
68 GraphicsBuffer::GraphicsBuffer()
73 m_buffer_shape_dirty = true;
75 m_buffer_usage = BufferUsageDynamicDraw;
77 SetUsage(BufferUsageStaticDraw);
80 GraphicsBuffer::~GraphicsBuffer()
86 glDeleteBuffers(1, &m_buffer_handle);
89 void GraphicsBuffer::SetType(GraphicsBuffer::BufferType bufType)
91 m_buffer_type = bufType;
94 void GraphicsBuffer::SetUsage(GraphicsBuffer::BufferUsage bufUsage)
96 if (bufUsage != m_buffer_usage)
98 m_buffer_usage = bufUsage;
99 m_buffer_shape_dirty = true;
103 void GraphicsBuffer::Invalidate()
105 m_invalidated = true;
106 if (!m_buffer_shape_dirty)
108 // Orphan the block of memory we're pointing to.
109 Upload(m_buffer_size, NULL);
111 // Apparently not supported.
112 //glInvalidateBufferData(m_buffer_handle);
115 bool GraphicsBuffer::RecreateBuffer(const void *data)
117 // If the buffer is not dirty, don't recreate it.
118 if (!m_buffer_shape_dirty) return false;
119 // If the buffer is mapped, don't recreate it.
120 if (!m_faking_map && m_map_pointer) return false;
121 // If the buffer has data in it we need, don't recreate it.
122 if (!m_invalidated) return false;
125 glDeleteBuffers(1, &m_buffer_handle);
127 glGenBuffers(1, &m_buffer_handle);
128 m_buffer_shape_dirty = false;
130 Upload(m_buffer_size, data);
134 void* GraphicsBuffer::Map(bool read, bool write, bool invalidate)
136 GLbitfield access = ((read)?GL_MAP_READ_BIT:0) | ((write)?GL_MAP_WRITE_BIT:0) | ((invalidate)?GL_MAP_INVALIDATE_BUFFER_BIT:0);
137 GLenum target = BufferTypeToGLType(m_buffer_type);
141 m_invalidated = true;
143 // Intel's Mesa driver does not rename the buffer when we map with GL_MAP_INVALIDATE_BUFFER_BIT,
144 // resulting in the CPU stalling waiting for rendering from the buffer to complete on the GPU.
145 // We manually force the buffer to be renamed here to avoid this.
146 m_buffer_shape_dirty = true;
150 Warn("Tried to map already mapped buffer!");
153 if (!read && m_buffer_usage == BufferUsage::BufferUsageStaticDraw)
155 m_map_pointer = malloc(m_buffer_size);
157 return m_map_pointer;
164 m_map_pointer = glMapBufferRange(target, 0, m_buffer_size, access);
166 return m_map_pointer;
169 void* GraphicsBuffer::MapRange(int offset, int length, bool read, bool write, bool invalidate)
171 GLbitfield access = ((read)?GL_MAP_READ_BIT:0) | ((write)?GL_MAP_WRITE_BIT:0) | ((invalidate)?GL_MAP_INVALIDATE_RANGE_BIT:0);
172 GLenum target = BufferTypeToGLType(m_buffer_type);
175 Warn("Tried to map already mapped buffer!");
181 m_map_pointer = glMapBufferRange(target, offset, length, access);
182 return m_map_pointer;
185 void GraphicsBuffer::UnMap()
187 GLenum target = BufferTypeToGLType(m_buffer_type);
191 Upload(m_buffer_size, m_map_pointer);
193 m_map_pointer = NULL;
194 m_invalidated = false;
195 m_faking_map = false;
200 glUnmapBuffer(target);
201 m_map_pointer = NULL;
202 m_invalidated = false;
205 void GraphicsBuffer::Upload(size_t length, const void* data)
207 GLenum target = BufferTypeToGLType(m_buffer_type);
209 GLenum usage = BufferUsageToGLUsage(m_buffer_usage);
211 m_invalidated = true;
212 m_buffer_size = length;
213 if (!RecreateBuffer(data))
216 glBufferData(target, length, data, usage);
219 m_invalidated = false;
222 void GraphicsBuffer::UploadRange(size_t length, intptr_t offset, const void* data)
224 GLenum target = BufferTypeToGLType(m_buffer_type);
229 glBufferSubData(target, offset, length, data);
230 m_invalidated = false;
233 void GraphicsBuffer::Resize(size_t length)
237 m_buffer_size = length;
241 // Create a new buffer and copy the old data into it.
243 GLuint old_buffer = m_buffer_handle;
244 glGenBuffers(1, &m_buffer_handle);
245 Upload(length, NULL);
246 glBindBuffer(GL_COPY_READ_BUFFER, old_buffer);
247 glBindBuffer(GL_COPY_WRITE_BUFFER, m_buffer_handle);
248 glCopyBufferSubData(GL_COPY_READ_BUFFER, GL_COPY_WRITE_BUFFER, 0, 0, m_buffer_size);
249 glDeleteBuffers(1, &old_buffer);
250 m_buffer_size = length;
254 void GraphicsBuffer::Bind() const
256 if (m_buffer_type == BufferTypeUniform)
257 glBindBufferBase(GL_UNIFORM_BUFFER, 0, m_buffer_handle);
259 glBindBuffer(BufferTypeToGLType(m_buffer_type), m_buffer_handle);