src/graphicsbuffer.cpp

   1 #include "graphicsbuffer.h"
   2 #include "log.h"
   3 #define GL_GLEXT_PROTOTYPES
   4 #include <SDL_opengl.h>
   5 #include <GL/glext.h>
   6
   7 using namespace IPDF;
   8
   9 static GLenum BufferUsageToGLUsage(GraphicsBuffer::BufferUsage buffer_usage)
  10 {
  11         GLenum usage;
  12         switch (buffer_usage)
  13         {
  14         case GraphicsBuffer::BufferUsageStaticDraw:
  15                 usage = GL_STATIC_DRAW;
  16                 break;
  17         case GraphicsBuffer::BufferUsageStaticRead:
  18                 usage = GL_STATIC_READ;
  19                 break;
  20         case GraphicsBuffer::BufferUsageStaticCopy:
  21                 usage = GL_STATIC_COPY;
  22                 break;
  23         case GraphicsBuffer::BufferUsageDynamicDraw:
  24                 usage = GL_DYNAMIC_DRAW;
  25                 break;
  26         case GraphicsBuffer::BufferUsageDynamicRead:
  27                 usage = GL_DYNAMIC_READ;
  28                 break;
  29         case GraphicsBuffer::BufferUsageDynamicCopy:
  30                 usage = GL_DYNAMIC_COPY;
  31                 break;
  32         case GraphicsBuffer::BufferUsageStreamDraw:
  33                 usage = GL_STREAM_DRAW;
  34                 break;
  35         case GraphicsBuffer::BufferUsageStreamRead:
  36                 usage = GL_STREAM_READ;
  37                 break;
  38         case GraphicsBuffer::BufferUsageStreamCopy:
  39                 usage = GL_STREAM_COPY;
  40                 break;
  41         default:
  42                 SDL_assert(false && "Unknown buffer usage type.");
  43                 usage = GL_DYNAMIC_DRAW;
  44         }
  45         return usage;
  46 }
  47
  48 static GLenum BufferTypeToGLType(GraphicsBuffer::BufferType buffer_type)
  49 {
  50         switch (buffer_type)
  51         {
  52         case GraphicsBuffer::BufferTypeVertex:
  53                 return GL_ARRAY_BUFFER;
  54         case GraphicsBuffer::BufferTypeIndex:
  55                 return GL_ELEMENT_ARRAY_BUFFER;
  56         case GraphicsBuffer::BufferTypePixelPack:
  57                 return GL_PIXEL_PACK_BUFFER;
  58         case GraphicsBuffer::BufferTypePixelUnpack:
  59                 return GL_PIXEL_UNPACK_BUFFER;
  60         case GraphicsBuffer::BufferTypeUniform:
  61                 return GL_UNIFORM_BUFFER;
  62         case GraphicsBuffer::BufferTypeDrawIndirect:
  63                 return GL_DRAW_INDIRECT_BUFFER;
  64         default:
  65                 return GL_COPY_READ_BUFFER;
  66         }
  67 }
  68
  69 GraphicsBuffer::GraphicsBuffer()
  70 {
  71         m_invalidated = true;
  72         m_buffer_size = 0;
  73         SetUsage(BufferUsageStaticDraw);
  74 }
  75
  76 GraphicsBuffer::~GraphicsBuffer()
  77 {
  78         if (m_map_pointer)
  79         {
  80                 UnMap();
  81         }
  82         glDeleteBuffers(1, &m_buffer_handle);
  83 }
  84
  85 void GraphicsBuffer::SetType(GraphicsBuffer::BufferType bufType)
  86 {
  87         glGenBuffers(1, &m_buffer_handle);
  88         m_buffer_type = bufType;
  89 }
  90
  91 void GraphicsBuffer::SetUsage(GraphicsBuffer::BufferUsage bufUsage)
  92 {
  93         m_buffer_usage = bufUsage;
  94 }
  95
  96 void* GraphicsBuffer::Map(bool read, bool write, bool invalidate)
  97 {
  98         GLbitfield access = ((read)?GL_MAP_READ_BIT:0) | ((write)?GL_MAP_WRITE_BIT:0) | ((invalidate)?GL_MAP_INVALIDATE_BUFFER_BIT:0);
  99         GLenum target = BufferTypeToGLType(m_buffer_type);
 100
 101         Bind();
 102
 103         return glMapBufferRange(target, 0, m_buffer_size, access);
 104
 105         //TODO: Emulate DSA
 106         //return glMapNamedBufferEXT(m_bufferHandle, access);
 107 }
 108
 109 void* GraphicsBuffer::MapRange(int offset, int length, bool read, bool write, bool invalidate)
 110 {
 111         GLbitfield access = ((read)?GL_MAP_READ_BIT:0) | ((write)?GL_MAP_WRITE_BIT:0) | ((invalidate)?GL_MAP_INVALIDATE_RANGE_BIT:0);
 112         GLenum target = BufferTypeToGLType(m_buffer_type);
 113
 114         Bind();
 115
 116         return glMapBufferRange(target, offset, length, access);
 117
 118         //TODO: Emulate DSA
 119         //return glMapNamedBufferRangeEXT(m_bufferHandle, offset, length, access);
 120 }
 121
 122 void GraphicsBuffer::UnMap()
 123 {
 124         GLenum target = BufferTypeToGLType(m_buffer_type);
 125
 126         Bind();
 127         glUnmapBuffer(target);
 128         //glUnmapNamedBufferEXT(m_bufferHandle);
 129 }
 130
 131 void GraphicsBuffer::Upload(size_t length, const void* data)
 132 {
 133         GLenum target = BufferTypeToGLType(m_buffer_type);
 134
 135         GLenum usage = BufferUsageToGLUsage(m_buffer_usage);
 136
 137         Bind();
 138         glBufferData(target, length, data, usage);
 139         m_buffer_size = length;
 140         //glNamedBufferDataEXT(m_bufferHandle, length, data, usage);
 141 }
 142
 143 void GraphicsBuffer::UploadRange(size_t length, intptr_t offset, const void* data)
 144 {
 145         GLenum target = BufferTypeToGLType(m_buffer_type);
 146
 147         Bind();
 148         glBufferSubData(target, offset, length, data);
 149         //glNamedBufferSubDataEXT(m_bufferHandle, offset, length, data);
 150 }
 151
 152 void GraphicsBuffer::Resize(size_t length)
 153 {
 154         if (m_invalidated)
 155         {
 156                 Upload(length, nullptr);
 157         }
 158         else
 159         {
 160                 // Create a new buffer and copy the old data into it.
 161                 UnMap();
 162                 GLuint old_buffer = m_buffer_handle;
 163                 glGenBuffers(1, &m_buffer_handle);
 164                 Upload(length, nullptr);
 165                 glBindBuffer(GL_COPY_READ_BUFFER, old_buffer);
 166                 glBindBuffer(GL_COPY_WRITE_BUFFER, m_buffer_handle);
 167                 glCopyBufferSubData(GL_COPY_READ_BUFFER, GL_COPY_WRITE_BUFFER, 0, 0, m_buffer_size);
 168                 glDeleteBuffers(1, &old_buffer);
 169         }
 170         m_buffer_size = length;
 171
 172 }
 173
 174 void GraphicsBuffer::Bind()
 175 {
 176         if (m_buffer_type == BufferTypeUniform)
 177                 glBindBufferBase(GL_UNIFORM_BUFFER, 0, m_buffer_handle);
 178         else
 179                 glBindBuffer(BufferTypeToGLType(m_buffer_type), m_buffer_handle);
 180 }
 181