src/graphicsbuffer.cpp

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