source/batch.cpp

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