source/buffer.cpp

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