source/batch.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgl
   4 Copyright © 2007-2010  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include "batch.h"
   9 #include "bindable.h"
  10 #include "buffer.h"
  11 #include "extension.h"
  12 #include "nv_primitive_restart.h"
  13 #include "vertexarray.h"
  14
  15 using namespace std;
  16
  17 namespace Msp {
  18 namespace GL {
  19
  20 unsigned Batch::restart_index = 0;
  21
  22 Batch::Batch(PrimitiveType t):
  23         prim_type(t),
  24         data_type(UNSIGNED_BYTE),
  25         min_index(0),
  26         max_index(0),
  27         restart(false),
  28         ibuf(0),
  29         ibuf_offset(0),
  30         next_in_ibuf(0),
  31         prev_in_ibuf(0),
  32         dirty(false)
  33 { }
  34
  35 Batch::~Batch()
  36 {
  37         unlink_from_ibuf();
  38 }
  39
  40 void Batch::set_data_type(DataType t)
  41 {
  42         if(t!=UNSIGNED_BYTE && t!=UNSIGNED_SHORT && t!=UNSIGNED_INT)
  43                 throw InvalidParameterValue("Batch data type must be an unsigned integer");
  44         if(t==UNSIGNED_BYTE && max_index>0xFE)
  45                 throw InvalidState("UNSIGNED_BYTE can't hold all indices in Batch");
  46         else if(t==UNSIGNED_SHORT && max_index>0xFFFE)
  47                 throw InvalidState("UNSIGNED_SHORT can't hold all indices in Batch");
  48
  49         if(data_type==UNSIGNED_BYTE && t==UNSIGNED_SHORT)
  50                 expand_data<unsigned char, unsigned short>();
  51         else if(data_type==UNSIGNED_BYTE && t==UNSIGNED_INT)
  52                 expand_data<unsigned char, unsigned>();
  53         else if(data_type==UNSIGNED_SHORT && t==UNSIGNED_INT)
  54                 expand_data<unsigned short, unsigned>();
  55         else if(data_type==UNSIGNED_INT && t==UNSIGNED_BYTE)
  56                 shrink_data<unsigned, unsigned char>();
  57         else if(data_type==UNSIGNED_INT && t==UNSIGNED_SHORT)
  58                 shrink_data<unsigned, unsigned short>();
  59         else if(data_type==UNSIGNED_SHORT && t==UNSIGNED_BYTE)
  60                 shrink_data<unsigned short, unsigned char>();
  61
  62         data_type = t;
  63         update_ibuf_offsets();
  64         dirty = true;
  65 }
  66
  67 void Batch::use_index_buffer(Buffer *buf, Batch *prev)
  68 {
  69         if(buf && prev && prev->ibuf!=buf)
  70                 throw InvalidParameterValue("Previous batch is not in the same buffer");
  71
  72         if(!buf)
  73         {
  74                 prev = 0;
  75                 unlink_from_ibuf();
  76         }
  77
  78         ibuf = buf;
  79         prev_in_ibuf = prev;
  80         next_in_ibuf = 0;
  81         if(prev)
  82         {
  83                 prev->next_in_ibuf = this;
  84                 ibuf_offset = prev->ibuf_offset+prev->data.size();
  85         }
  86         else
  87                 ibuf_offset = 0;
  88
  89         dirty = true;
  90 }
  91
  92 Batch &Batch::append(unsigned i)
  93 {
  94         if(data.empty())
  95                 min_index = max_index = i;
  96         else
  97         {
  98                 min_index = min(min_index, i);
  99                 max_index = max(max_index, i);
 100         }
 101
 102         if((data_type==UNSIGNED_BYTE || data_type==UNSIGNED_SHORT) && max_index>0xFFFE)
 103                 set_data_type(UNSIGNED_INT);
 104         else if(data_type==UNSIGNED_BYTE && max_index>0xFE)
 105                 set_data_type(UNSIGNED_SHORT);
 106
 107         if(data_type==UNSIGNED_SHORT)
 108                 append_index<unsigned short>(i);
 109         else if(data_type==UNSIGNED_INT)
 110                 append_index<unsigned>(i);
 111         else
 112                 data.push_back(i);
 113
 114         update_ibuf_offsets();
 115         dirty = true;
 116
 117         return *this;
 118 }
 119
 120 void Batch::append(const vector<unsigned> &ind)
 121 {
 122         data.reserve(data.size()+ind.size()*get_index_size());
 123         for(vector<unsigned>::const_iterator i=ind.begin(); i!=ind.end(); ++i)
 124                 append(*i);
 125 }
 126
 127 void Batch::append(const Batch &other)
 128 {
 129         if(other.prim_type!=prim_type)
 130                 throw InvalidParameterValue("Can't concatenate batches with different primitive types");
 131         if(prim_type==LINE_STRIP || prim_type==LINE_LOOP)
 132                 throw InvalidState("Can't concatenate line strips or loops");
 133         else if(prim_type==POLYGON)
 134                 throw InvalidState("Can't concatenate polygons");
 135         else if(prim_type==TRIANGLE_FAN)
 136                 static RequireExtension _ext("GL_NV_primitive_restart");
 137
 138         if(other.data.empty())
 139                 return;
 140
 141         if(is_supported("GL_NV_primitive_restart"))
 142         {
 143                 restart = true;
 144                 if(data_type==UNSIGNED_SHORT)
 145                         append_index<unsigned short>(0xFFFF);
 146                 else if(data_type==UNSIGNED_INT)
 147                         append_index<unsigned>(0xFFFFFFFF);
 148                 else
 149                         data.push_back(0xFF);
 150         }
 151         else if(prim_type==TRIANGLE_STRIP)
 152         {
 153                 append(get_index(size()-1));
 154                 append(other.get_index(0));
 155                 if(size()&1)
 156                         append(other.get_index(0));
 157         }
 158         else if(prim_type==QUAD_STRIP)
 159         {
 160                 append(get_index(size()-1));
 161                 append(get_index(size()-1));
 162                 append(other.get_index(0));
 163                 append(other.get_index(0));
 164         }
 165
 166         unsigned count = other.size();
 167         for(unsigned i=0; i<count; ++i)
 168                 append(other.get_index(i));
 169 }
 170
 171 void Batch::draw() const
 172 {
 173         if(restart)
 174         {
 175                 unsigned index;
 176                 if(data_type==UNSIGNED_SHORT)
 177                         index = 0xFFFF;
 178                 else if(data_type==UNSIGNED_INT)
 179                         index = 0xFFFFFFFF;
 180                 else
 181                         index = 0xFF;
 182
 183                 if(index!=restart_index)
 184                 {
 185                         if(!restart_index)
 186                                 glEnableClientState(GL_PRIMITIVE_RESTART_NV);
 187                         glPrimitiveRestartIndexNV(index);
 188                         restart_index = index;
 189                 }
 190         }
 191         else if(restart_index && restart_index<max_index)
 192         {
 193                 glDisableClientState(GL_PRIMITIVE_RESTART_NV);
 194                 restart_index = 0;
 195         }
 196
 197         if(ibuf)
 198         {
 199                 if(dirty)
 200                 {
 201                         const Batch *b = this;
 202                         for(; b->prev_in_ibuf; b=b->prev_in_ibuf) ;
 203
 204                         unsigned chain_size = 0;
 205                         for(const Batch *a=b; a; a=a->next_in_ibuf)
 206                                 chain_size += a->data.size();
 207
 208                         ibuf->data(chain_size, 0);
 209
 210                         for(; b; b=b->next_in_ibuf)
 211                         {
 212                                 ibuf->sub_data(b->ibuf_offset, b->data.size(), &b->data[0]);
 213                                 b->dirty = false;
 214                         }
 215                 }
 216
 217                 BufferAlias<ELEMENT_ARRAY_BUFFER> alias(*ibuf);
 218                 Bind bind_ibuf(alias, true);
 219
 220                 glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, (void *)ibuf_offset);
 221         }
 222         else
 223                 glDrawRangeElements(prim_type, min_index, max_index, size(), data_type, &data[0]);
 224 }
 225
 226 unsigned Batch::get_index_size() const
 227 {
 228         if(data_type==UNSIGNED_SHORT)
 229                 return sizeof(unsigned short);
 230         else if(data_type==UNSIGNED_INT)
 231                 return sizeof(unsigned);
 232         return sizeof(unsigned char);
 233 }
 234
 235 template<typename T>
 236 void Batch::append_index(T i)
 237 {
 238         data.insert(data.end(), sizeof(T), 0);
 239         *(T *)(&data[data.size()-sizeof(T)]) = i;
 240 }
 241
 242 unsigned Batch::get_index(unsigned i) const
 243 {
 244         if(data_type==UNSIGNED_SHORT)
 245                 return *(unsigned short *)&data[i*sizeof(unsigned short)];
 246         else if(data_type==UNSIGNED_INT)
 247                 return *(unsigned *)&data[i*sizeof(unsigned )];
 248         else
 249                 return data[i];
 250 }
 251
 252 template<typename T, typename U>
 253 void Batch::expand_data()
 254 {
 255         unsigned count = data.size()/sizeof(T);
 256         data.resize(count*sizeof(U));
 257         for(unsigned i=count; i--;)
 258                 *(U *)(&data[i*sizeof(U)]) = convert<T, U>(*(T *)(&data[i*sizeof(T)]));
 259 }
 260
 261 template<typename T, typename U>
 262 void Batch::shrink_data()
 263 {
 264         unsigned count = data.size()/sizeof(T);
 265         for(unsigned i=0; i<count; ++i)
 266                 *(U *)(&data[i*sizeof(U)]) = convert<T, U>(*(T *)(&data[i*sizeof(T)]));
 267         data.resize(count*sizeof(U));
 268 }
 269
 270 template<typename T, typename U>
 271 U Batch::convert(T i) const
 272 {
 273         if(!static_cast<T>(~i))
 274                 return ~0;
 275         else
 276                 return i;
 277 }
 278
 279 void Batch::unlink_from_ibuf()
 280 {
 281         if(next_in_ibuf)
 282                 next_in_ibuf->prev_in_ibuf = prev_in_ibuf;
 283         if(prev_in_ibuf)
 284         {
 285                 prev_in_ibuf->next_in_ibuf = next_in_ibuf;
 286                 prev_in_ibuf->update_ibuf_offsets();
 287         }
 288         else if(next_in_ibuf)
 289         {
 290                 next_in_ibuf->ibuf_offset = 0;
 291                 next_in_ibuf->update_ibuf_offsets();
 292         }
 293 }
 294
 295 void Batch::update_ibuf_offsets()
 296 {
 297         for(Batch *b=this; b->next_in_ibuf; b=b->next_in_ibuf)
 298                 b->next_in_ibuf->ibuf_offset = b->ibuf_offset+b->data.size();
 299 }
 300
 301
 302 Batch::Loader::Loader(Batch &b):
 303         DataFile::ObjectLoader<Batch>(b)
 304 {
 305         add("indices", &Loader::indices);
 306 }
 307
 308 void Batch::Loader::indices(const vector<unsigned> &ind)
 309 {
 310         obj.append(ind);
 311 }
 312
 313 } // namespace GL
 314 } // namespace Msp