source/buffer.cpp

   1 #include "arb_vertex_buffer_object.h"
   2 #include "extension.h"
   3 #include "buffer.h"
   4
   5 namespace Msp {
   6 namespace GL {
   7
   8 Buffer::Buffer(BufferType t):
   9         type(t),
  10         usage(STATIC_DRAW)
  11 {
  12         static RequireExtension _req_vbo("GL_ARB_vertex_buffer_object");
  13         if(type==PIXEL_PACK_BUFFER || type==PIXEL_UNPACK_BUFFER)
  14                 static RequireExtension _req_pbo("GL_ARB_pixel_buffer_object");
  15
  16         glGenBuffersARB(1, &id);
  17 }
  18
  19 Buffer::~Buffer()
  20 {
  21         glDeleteBuffersARB(1, &id);
  22 }
  23
  24 void Buffer::set_usage(BufferUsage u)
  25 {
  26         usage = u;
  27 }
  28
  29 void Buffer::data(unsigned size, const void *d)
  30 {
  31         const Buffer *old = current(type);
  32         bind();
  33         glBufferDataARB(type, size, d, usage);
  34         restore(old, type);
  35 }
  36
  37 void Buffer::sub_data(unsigned offset, unsigned size, const void *d)
  38 {
  39         const Buffer *old = current(type);
  40         bind();
  41         glBufferSubDataARB(type, offset, size, d);
  42         restore(old, type);
  43 }
  44
  45 void Buffer::bind_to(BufferType t) const
  46 {
  47         const Buffer *&ptr = binding(t);
  48         if(ptr!=this)
  49         {
  50                 glBindBufferARB(t, id);
  51                 ptr = this;
  52         }
  53 }
  54
  55 void Buffer::unbind_from(BufferType type)
  56 {
  57         const Buffer *&ptr = binding(type);
  58         if(ptr)
  59         {
  60                 glBindBufferARB(type, 0);
  61                 ptr = 0;
  62         }
  63 }
  64
  65 const Buffer *&Buffer::binding(BufferType type)
  66 {
  67         switch(type)
  68         {
  69         case ARRAY_BUFFER:         return bound[0];
  70         case ELEMENT_ARRAY_BUFFER: return bound[1];
  71         case PIXEL_PACK_BUFFER:    return bound[2];
  72         case PIXEL_UNPACK_BUFFER:  return bound[3];
  73         default: throw InvalidParameterValue("Invalid buffer type");
  74         }
  75 }
  76
  77 void Buffer::restore(const Buffer *buf, BufferType type)
  78 {
  79         if(buf!=current(type))
  80         {
  81                 if(buf)
  82                         buf->bind_to(type);
  83                 else
  84                         unbind_from(type);
  85         }
  86 }
  87
  88 const Buffer *Buffer::bound[4] = { 0, 0, 0, 0 };
  89
  90 } // namespace GL
  91 } // namespace Msp