source/buffer.cpp

   1 #include <stdexcept>
   2 #include <msp/gl/extensions/arb_pixel_buffer_object.h>
   3 #include <msp/gl/extensions/arb_uniform_buffer_object.h>
   4 #include <msp/gl/extensions/arb_vertex_buffer_object.h>
   5 #include "buffer.h"
   6 #include "error.h"
   7 #include "mesh.h"
   8 #include "misc.h"
   9
  10 using namespace std;
  11
  12 namespace Msp {
  13 namespace GL {
  14
  15 const Buffer *Buffer::bound[5] = { 0, 0, 0, 0, 0 };
  16 BufferType buffer_types[] = { ARRAY_BUFFER, ELEMENT_ARRAY_BUFFER, PIXEL_PACK_BUFFER, PIXEL_UNPACK_BUFFER, UNIFORM_BUFFER };
  17
  18 Buffer::Buffer(BufferType t):
  19         type(t),
  20         usage(STATIC_DRAW),
  21         size(0)
  22 {
  23         require_buffer_type(type);
  24
  25         glGenBuffers(1, &id);
  26 }
  27
  28 Buffer::~Buffer()
  29 {
  30         for(unsigned i=0; i<5; ++i)
  31                 if(bound[i]==this)
  32                         unbind_from(buffer_types[i]);
  33         glDeleteBuffers(1, &id);
  34 }
  35
  36 void Buffer::require_buffer_type(BufferType type)
  37 {
  38         static Require _req_vbo(ARB_vertex_buffer_object);
  39         if(type==PIXEL_PACK_BUFFER || type==PIXEL_UNPACK_BUFFER)
  40                 static Require _req_pbo(ARB_pixel_buffer_object);
  41         else if(type==UNIFORM_BUFFER)
  42                 static Require _req_ubo(ARB_uniform_buffer_object);
  43 }
  44
  45 void Buffer::set_usage(BufferUsage u)
  46 {
  47         usage = u;
  48 }
  49
  50 void Buffer::data(unsigned sz, const void *d)
  51 {
  52         BindRestore _bind(this, type);
  53         glBufferData(type, sz, d, usage);
  54         size = sz;
  55 }
  56
  57 void Buffer::sub_data(unsigned off, unsigned sz, const void *d)
  58 {
  59         BindRestore _bind(this, type);
  60         glBufferSubData(type, off, sz, d);
  61 }
  62
  63 BufferRange *Buffer::create_range(unsigned s, unsigned o)
  64 {
  65         return new BufferRange(*this, s, o);
  66 }
  67
  68 void *Buffer::map(BufferAccess access)
  69 {
  70         BindRestore _bind(this, type);
  71         return glMapBuffer(type, access);
  72 }
  73
  74 bool Buffer::unmap()
  75 {
  76         BindRestore _bind(this, type);
  77         return glUnmapBuffer(type);
  78 }
  79
  80 void Buffer::bind_to(BufferType t) const
  81 {
  82         if(t!=type)
  83                 require_buffer_type(t);
  84         if(t==ELEMENT_ARRAY_BUFFER)
  85                 if(const Mesh *m = Mesh::current())
  86                 {
  87                         // Don't change the binding in a mesh's vertex array object
  88                         if(this==m->get_index_buffer())
  89                                 return;
  90                         throw invalid_operation("Buffer::bind_to(ELEMENT_ARRAY_BUFFER)");
  91                 }
  92         if(set_current(t, this))
  93                 glBindBuffer(t, id);
  94 }
  95
  96 const Buffer *Buffer::current(BufferType t)
  97 {
  98         if(t==ELEMENT_ARRAY_BUFFER)
  99                 if(const Mesh *m = Mesh::current())
 100                         return m->get_index_buffer();
 101         return binding(t);
 102 }
 103
 104 void Buffer::unbind_from(BufferType type)
 105 {
 106         if(type==ELEMENT_ARRAY_BUFFER && Mesh::current())
 107                 throw invalid_operation("Buffer::unbind_from(ELEMENT_ARRAY_BUFFER)");
 108         if(set_current(type, 0))
 109                 glBindBuffer(type, 0);
 110 }
 111
 112 const Buffer *&Buffer::binding(BufferType type)
 113 {
 114         switch(type)
 115         {
 116         case ARRAY_BUFFER:         return bound[0];
 117         case ELEMENT_ARRAY_BUFFER: return bound[1];
 118         case PIXEL_PACK_BUFFER:    return bound[2];
 119         case PIXEL_UNPACK_BUFFER:  return bound[3];
 120         case UNIFORM_BUFFER:       return bound[4];
 121         default: throw invalid_argument("Buffer::binding");
 122         }
 123 }
 124
 125 bool Buffer::set_current(BufferType type, const Buffer *buf)
 126 {
 127         const Buffer *&ptr = binding(type);
 128         if(ptr==buf)
 129                 return false;
 130
 131         ptr = buf;
 132         return true;
 133 }
 134
 135
 136 vector<const BufferRange *> BufferRange::bound_uniform;
 137
 138 BufferRange::BufferRange(Buffer &b, unsigned o, unsigned s):
 139         buffer(b),
 140         offset(o),
 141         size(s)
 142 {
 143         if(o>buffer.get_size() || o+s>buffer.get_size())
 144                 throw out_of_range("BufferRange::BufferRange");
 145 }
 146
 147 BufferRange::~BufferRange()
 148 {
 149         for(unsigned i=0; i<bound_uniform.size(); ++i)
 150                 if(bound_uniform[i]==this)
 151                         unbind_from(UNIFORM_BUFFER, i);
 152 }
 153
 154 void BufferRange::data(const void *d)
 155 {
 156         buffer.sub_data(offset, size, d);
 157 }
 158
 159 void BufferRange::bind_to(BufferType t, unsigned i)
 160 {
 161         if(t!=buffer.type)
 162                 Buffer::require_buffer_type(t);
 163         if(set_current(t, i, this))
 164         {
 165                 // The buffer gets bound as a side effect
 166                 Buffer::set_current(t, &buffer);
 167                 glBindBufferRange(t, i, buffer.id, offset, size);
 168         }
 169 }
 170
 171 void BufferRange::unbind_from(BufferType t, unsigned i)
 172 {
 173         if(set_current(t, i, 0))
 174         {
 175                 Buffer::set_current(t, 0);
 176                 glBindBufferBase(t, i, 0);
 177         }
 178 }
 179
 180 const BufferRange *&BufferRange::binding(BufferType type, unsigned index)
 181 {
 182         if(type==UNIFORM_BUFFER)
 183         {
 184                 if(index>=get_n_uniform_buffer_bindings())
 185                         throw out_of_range("BufferRange::binding");
 186                 if(bound_uniform.size()<=index)
 187                         bound_uniform.resize(index+1);
 188                 return bound_uniform[index];
 189         }
 190         else
 191                 throw invalid_argument("BufferRange::binding");
 192 }
 193
 194 bool BufferRange::set_current(BufferType type, unsigned index, const BufferRange *buf)
 195 {
 196         const BufferRange *&ptr = binding(type, index);
 197         if(ptr==buf)
 198                 return false;
 199
 200         ptr = buf;
 201         return true;
 202 }
 203
 204 unsigned BufferRange::get_n_uniform_buffer_bindings()
 205 {
 206         static unsigned count = get_i(GL_MAX_UNIFORM_BUFFER_BINDINGS);
 207         return count;
 208 }
 209
 210 unsigned BufferRange::get_uniform_buffer_alignment()
 211 {
 212         static unsigned align = get_i(GL_UNIFORM_BUFFER_OFFSET_ALIGNMENT);
 213         return align;
 214 }
 215
 216 } // namespace GL
 217 } // namespace Msp