source/batch.cpp

   1 #include <msp/gl/extensions/ext_draw_range_elements.h>
   2 #include <msp/gl/extensions/msp_legacy_features.h>
   3 #include <msp/gl/extensions/msp_primitive_restart.h>
   4 #include <msp/gl/extensions/nv_primitive_restart.h>
   5 #include "batch.h"
   6 #include "bindable.h"
   7 #include "buffer.h"
   8 #include "error.h"
   9 #include "mesh.h"
  10 #include "vertexarray.h"
  11
  12 using namespace std;
  13
  14 namespace {
  15
  16 template<typename T>
  17 void append(vector<unsigned char> &data, T i)
  18 {
  19         data.insert(data.end(), sizeof(T), 0);
  20         *(T *)(&data[data.size()-sizeof(T)]) = i;
  21 }
  22
  23 template<typename T, typename U>
  24 U convert(T n)
  25 {
  26         if(!static_cast<T>(~n))
  27                 return ~0;
  28         else
  29                 return n;
  30 }
  31
  32 template<typename T, typename U>
  33 void expand(vector<unsigned char> &data)
  34 {
  35         unsigned count = data.size()/sizeof(T);
  36         data.resize(count*sizeof(U));
  37         for(unsigned i=count; i--;)
  38                 *(U *)(&data[i*sizeof(U)]) = convert<T, U>(*(T *)(&data[i*sizeof(T)]));
  39 }
  40
  41 template<typename T, typename U>
  42 void shrink(vector<unsigned char> &data)
  43 {
  44         unsigned count = data.size()/sizeof(T);
  45         for(unsigned i=0; i<count; ++i)
  46                 *(U *)(&data[i*sizeof(U)]) = convert<T, U>(*(T *)(&data[i*sizeof(T)]));
  47         data.resize(count*sizeof(U));
  48 }
  49
  50 }
  51
  52 namespace Msp {
  53 namespace GL {
  54
  55 unsigned Batch::restart_index = 0;
  56
  57 Batch::Batch(PrimitiveType t):
  58         prim_type(t),
  59         data_type(UNSIGNED_BYTE),
  60         min_index(0),
  61         max_index(0),
  62         restart(false)
  63 {
  64         /* Make sure we have glEnable/DisableClientState to go with
  65         NV_primitive_restart */
  66         if(!MSP_primitive_restart && NV_primitive_restart)
  67                 (void)(bool)MSP_legacy_features;
  68 }
  69
  70 Batch::~Batch()
  71 {
  72 }
  73
  74 void Batch::set_data_type(DataType t)
  75 {
  76         if(t!=UNSIGNED_BYTE && t!=UNSIGNED_SHORT && t!=UNSIGNED_INT)
  77                 throw invalid_argument("Batch::set_data_type");
  78         if(t==UNSIGNED_BYTE && max_index>0xFE)
  79                 throw invalid_operation("Batch::set_data_type");
  80         else if(t==UNSIGNED_SHORT && max_index>0xFFFE)
  81                 throw invalid_operation("Batch::set_data_type");
  82
  83         if(data_type==UNSIGNED_BYTE && t==UNSIGNED_SHORT)
  84                 expand<unsigned char, unsigned short>(data);
  85         else if(data_type==UNSIGNED_BYTE && t==UNSIGNED_INT)
  86                 expand<unsigned char, unsigned>(data);
  87         else if(data_type==UNSIGNED_SHORT && t==UNSIGNED_INT)
  88                 expand<unsigned short, unsigned>(data);
  89         else if(data_type==UNSIGNED_INT && t==UNSIGNED_BYTE)
  90                 shrink<unsigned, unsigned char>(data);
  91         else if(data_type==UNSIGNED_INT && t==UNSIGNED_SHORT)
  92                 shrink<unsigned, unsigned short>(data);
  93         else if(data_type==UNSIGNED_SHORT && t==UNSIGNED_BYTE)
  94                 shrink<unsigned short, unsigned char>(data);
  95
  96         data_type = t;
  97         update_offset();
  98         dirty = true;
  99 }
 100
 101 Batch &Batch::append(unsigned i)
 102 {
 103         append_index(i);
 104
 105         update_offset();
 106         dirty = true;
 107
 108         return *this;
 109 }
 110
 111 void Batch::append(const vector<unsigned> &ind)
 112 {
 113         if(ind.empty())
 114                 return;
 115
 116         data.reserve(data.size()+ind.size()*get_index_size());
 117         for(vector<unsigned>::const_iterator i=ind.begin(); i!=ind.end(); ++i)
 118                 append_index(*i);
 119
 120         update_offset();
 121         dirty = true;
 122 }
 123
 124 bool Batch::can_append(PrimitiveType other_type)
 125 {
 126         if(other_type!=prim_type)
 127                 return false;
 128         else if(prim_type==LINE_STRIP || prim_type==LINE_LOOP || prim_type==TRIANGLE_FAN)
 129                 return MSP_primitive_restart || NV_primitive_restart;
 130         else
 131                 return true;
 132 }
 133
 134 void Batch::append(const Batch &other)
 135 {
 136         if(other.prim_type!=prim_type)
 137                 throw invalid_argument("Batch::append");
 138         if(prim_type==LINE_STRIP || prim_type==LINE_LOOP || prim_type==TRIANGLE_FAN)
 139         {
 140                 if(!MSP_primitive_restart)
 141                         static Require _req(NV_primitive_restart);
 142         }
 143
 144         if(other.data.empty())
 145                 return;
 146
 147         if(prim_type==POINTS || prim_type==LINES || prim_type==TRIANGLES || prim_type==QUADS)
 148                 ;
 149         else if(MSP_primitive_restart || NV_primitive_restart)
 150         {
 151                 restart = true;
 152                 if(data_type==UNSIGNED_SHORT)
 153                         ::append<unsigned short>(data, 0xFFFF);
 154                 else if(data_type==UNSIGNED_INT)
 155                         ::append<unsigned>(data, 0xFFFFFFFF);
 156                 else
 157                         data.push_back(0xFF);
 158         }
 159         else if(prim_type==TRIANGLE_STRIP)
 160         {
 161                 append(get_index(size()-1));
 162                 append(other.get_index(0));
 163                 if(size()&1)
 164                         append(other.get_index(0));
 165         }
 166         else if(prim_type==QUAD_STRIP)
 167         {
 168                 append(get_index(size()-1));
 169                 append(get_index(size()-1));
 170                 append(other.get_index(0));
 171                 append(other.get_index(0));
 172         }
 173
 174         unsigned count = other.size();
 175         for(unsigned i=0; i<count; ++i)
 176                 append_index(other.get_index(i));
 177
 178         update_offset();
 179         dirty = true;
 180 }
 181
 182 void Batch::append_index(unsigned i)
 183 {
 184         if(data.empty())
 185                 min_index = max_index = i;
 186         else
 187         {
 188                 min_index = min(min_index, i);
 189                 max_index = max(max_index, i);
 190         }
 191
 192         if((data_type==UNSIGNED_BYTE || data_type==UNSIGNED_SHORT) && max_index>0xFFFE)
 193                 set_data_type(UNSIGNED_INT);
 194         else if(data_type==UNSIGNED_BYTE && max_index>0xFE)
 195                 set_data_type(UNSIGNED_SHORT);
 196
 197         if(data_type==UNSIGNED_SHORT)
 198                 ::append<unsigned short>(data, i);
 199         else if(data_type==UNSIGNED_INT)
 200                 ::append<unsigned>(data, i);
 201         else
 202                 data.push_back(i);
 203 }
 204
 205 unsigned Batch::get_index_size() const
 206 {
 207         if(data_type==UNSIGNED_SHORT)
 208                 return sizeof(unsigned short);
 209         else if(data_type==UNSIGNED_INT)
 210                 return sizeof(unsigned);
 211         return sizeof(unsigned char);
 212 }
 213
 214 unsigned Batch::get_index(unsigned i) const
 215 {
 216         if(data_type==UNSIGNED_SHORT)
 217                 return *(unsigned short *)&data[i*sizeof(unsigned short)];
 218         else if(data_type==UNSIGNED_INT)
 219                 return *(unsigned *)&data[i*sizeof(unsigned )];
 220         else
 221                 return data[i];
 222 }
 223
 224 void Batch::draw() const
 225 {
 226         if(restart)
 227         {
 228                 unsigned index;
 229                 if(data_type==UNSIGNED_SHORT)
 230                         index = 0xFFFF;
 231                 else if(data_type==UNSIGNED_INT)
 232                         index = 0xFFFFFFFF;
 233                 else
 234                         index = 0xFF;
 235
 236                 if(index!=restart_index)
 237                         set_restart_index(index);
 238         }
 239         else if(restart_index && restart_index<=max_index)
 240                 set_restart_index(0);
 241
 242         Buffer *ibuf = get_buffer();
 243         const void *data_ptr;
 244         BindRestore _bind_ibuf(ibuf, ELEMENT_ARRAY_BUFFER);
 245         if(ibuf)
 246         {
 247                 if(dirty)
 248                         update_buffer();
 249
 250                 data_ptr = reinterpret_cast<const void *>(get_offset());
 251         }
 252         else
 253                 data_ptr = &data[0];
 254
 255         if(EXT_draw_range_elements)
 256                 glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, data_ptr);
 257         else
 258                 glDrawElements(prim_type, size(), data_type, data_ptr);
 259 }
 260
 261 void Batch::set_restart_index(unsigned index)
 262 {
 263         if(MSP_primitive_restart)
 264         {
 265                 if(index>0)
 266                 {
 267                         if(!restart_index)
 268                                 glEnable(GL_PRIMITIVE_RESTART);
 269                         glPrimitiveRestartIndex(index);
 270                 }
 271                 else
 272                         glDisable(GL_PRIMITIVE_RESTART);
 273         }
 274         else
 275         {
 276                 if(index>0)
 277                 {
 278                         if(!restart_index)
 279                                 glEnableClientState(GL_PRIMITIVE_RESTART_NV);
 280                         glPrimitiveRestartIndexNV(index);
 281                 }
 282                 else
 283                         glDisableClientState(GL_PRIMITIVE_RESTART_NV);
 284         }
 285
 286         restart_index = index;
 287 }
 288
 289
 290 Batch::Loader::Loader(Batch &b):
 291         DataFile::ObjectLoader<Batch>(b)
 292 {
 293         add("indices", &Loader::indices);
 294 }
 295
 296 void Batch::Loader::indices(const vector<unsigned> &ind)
 297 {
 298         obj.append(ind);
 299 }
 300
 301 } // namespace GL
 302 } // namespace Msp