source/core/batch.cpp

   1 #include "batch.h"
   2 #include "error.h"
   3
   4 using namespace std;
   5
   6 namespace {
   7
   8 template<typename T>
   9 void append(vector<uint8_t> &data, T i)
  10 {
  11         data.insert(data.end(), sizeof(T), 0);
  12         *(T *)(&data[data.size()-sizeof(T)]) = i;
  13 }
  14
  15 template<typename T, typename U>
  16 U convert(T n)
  17 {
  18         if(!static_cast<T>(~n))
  19                 return ~0;
  20         else
  21                 return n;
  22 }
  23
  24 template<typename T, typename U>
  25 void expand(vector<uint8_t> &data)
  26 {
  27         unsigned count = data.size()/sizeof(T);
  28         data.resize(count*sizeof(U));
  29         for(unsigned i=count; i--;)
  30                 *(U *)(&data[i*sizeof(U)]) = convert<T, U>(*(T *)(&data[i*sizeof(T)]));
  31 }
  32
  33 template<typename T, typename U>
  34 void shrink(vector<uint8_t> &data)
  35 {
  36         unsigned count = data.size()/sizeof(T);
  37         for(unsigned i=0; i<count; ++i)
  38                 *(U *)(&data[i*sizeof(U)]) = convert<T, U>(*(T *)(&data[i*sizeof(T)]));
  39         data.resize(count*sizeof(U));
  40 }
  41
  42 }
  43
  44 namespace Msp {
  45 namespace GL {
  46
  47 Batch::Batch(PrimitiveType t):
  48         BatchBackend(t),
  49         prim_type(t),
  50         index_type(VOID),
  51         max_index(0)
  52 {
  53         set_index_type(UNSIGNED_SHORT);
  54 }
  55
  56 void Batch::set_index_type(DataType t)
  57 {
  58         if(t==index_type)
  59                 return;
  60         if(t!=UNSIGNED_SHORT && t!=UNSIGNED_INT)
  61                 throw invalid_argument("Batch::set_data_type");
  62         if(t==UNSIGNED_SHORT && max_index>0xFFFE)
  63                 throw invalid_operation("Batch::set_data_type");
  64
  65         if(index_type==UNSIGNED_SHORT && t==UNSIGNED_INT)
  66                 expand<uint16_t, uint32_t>(data);
  67         else if(index_type==UNSIGNED_INT && t==UNSIGNED_SHORT)
  68                 shrink<uint32_t, uint16_t>(data);
  69
  70         index_type = t;
  71         BatchBackend::set_index_type(t);
  72         update_offset();
  73         mark_dirty();
  74 }
  75
  76 void Batch::set_patch_size(unsigned s)
  77 {
  78         if(prim_type!=PATCHES)
  79                 throw invalid_operation("Batch::set_patch_size");
  80         if(s<1)
  81                 throw invalid_argument("Batch::set_patch_size");
  82
  83         patch_size = s;
  84 }
  85
  86 Batch &Batch::append(unsigned i)
  87 {
  88         append_index(i);
  89
  90         update_offset();
  91         mark_dirty();
  92
  93         return *this;
  94 }
  95
  96 Batch &Batch::append(const vector<unsigned> &ind)
  97 {
  98         if(ind.empty())
  99                 return *this;
 100
 101         data.reserve(data.size()+ind.size()*get_index_size());
 102         for(unsigned i: ind)
 103                 append_index(i);
 104
 105         update_offset();
 106         mark_dirty();
 107
 108         return *this;
 109 }
 110
 111 bool Batch::can_append(PrimitiveType other_type)
 112 {
 113         if(other_type!=prim_type)
 114                 return false;
 115         else if(prim_type==LINE_STRIP || prim_type==TRIANGLE_FAN)
 116                 return check_restart(false);
 117         else
 118                 return true;
 119 }
 120
 121 Batch &Batch::append(const Batch &other)
 122 {
 123         if(other.prim_type!=prim_type)
 124                 throw invalid_argument("Batch::append");
 125         if(prim_type==LINE_STRIP || prim_type==TRIANGLE_FAN)
 126                 check_restart(true);
 127
 128         if(other.data.empty())
 129                 return *this;
 130
 131         // TODO allow appending triangles to a triangle strip
 132
 133         if(prim_type==POINTS || prim_type==LINES || prim_type==TRIANGLES)
 134                 ;
 135         else if(check_restart(false))
 136         {
 137                 if(index_type==UNSIGNED_INT)
 138                         ::append<uint32_t>(data, 0xFFFFFFFF);
 139                 else
 140                         ::append<uint16_t>(data, 0xFFFF);
 141         }
 142         else if(prim_type==TRIANGLE_STRIP)
 143         {
 144                 append(get_index(size()-1));
 145                 append(other.get_index(0));
 146                 if(size()&1)
 147                         append(other.get_index(0));
 148         }
 149
 150         unsigned count = other.size();
 151         for(unsigned i=0; i<count; ++i)
 152                 append_index(other.get_index(i));
 153
 154         update_offset();
 155         mark_dirty();
 156
 157         return *this;
 158 }
 159
 160 void Batch::append_index(unsigned i)
 161 {
 162         if(data.empty())
 163                 max_index = i;
 164         else
 165                 max_index = max(max_index, i);
 166
 167         if(index_type==UNSIGNED_SHORT && max_index>0xFFFE)
 168                 set_index_type(UNSIGNED_INT);
 169
 170         if(index_type==UNSIGNED_INT)
 171                 ::append<uint32_t>(data, i);
 172         else
 173                 ::append<uint16_t>(data, i);
 174 }
 175
 176 unsigned Batch::get_index(size_t i) const
 177 {
 178         if(index_type==UNSIGNED_INT)
 179                 return *(uint32_t *)&data[i*sizeof(uint32_t)];
 180         else
 181                 return *(uint16_t *)&data[i*sizeof(uint16_t)];
 182 }
 183
 184
 185 Batch::Loader::Loader(Batch &b):
 186         DataFile::ObjectLoader<Batch>(b)
 187 {
 188         add("indices", &Loader::indices);
 189         add("patch_size", &Loader::patch_size);
 190 }
 191
 192 void Batch::Loader::indices(const vector<unsigned> &ind)
 193 {
 194         obj.append(ind);
 195 }
 196
 197 void Batch::Loader::patch_size(unsigned s)
 198 {
 199         obj.set_patch_size(s);
 200 }
 201
 202 } // namespace GL
 203 } // namespace Msp