source/glsl/compatibility.cpp

   1 #include <msp/core/algorithm.h>
   2 #include <msp/core/raii.h>
   3 #include <msp/strings/lexicalcast.h>
   4 #include "compatibility.h"
   5 #include "glsl_error.h"
   6
   7 using namespace std;
   8
   9 namespace Msp {
  10 namespace GL {
  11 namespace SL {
  12
  13 DefaultPrecisionGenerator::DefaultPrecisionGenerator():
  14         stage(0)
  15 { }
  16
  17 void DefaultPrecisionGenerator::apply(Stage &s)
  18 {
  19         stage = &s;
  20         s.content.visit(*this);
  21 }
  22
  23 void DefaultPrecisionGenerator::visit(Block &block)
  24 {
  25         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
  26         {
  27                 if(&block==&stage->content)
  28                         insert_point = i;
  29                 (*i)->visit(*this);
  30         }
  31 }
  32
  33 void DefaultPrecisionGenerator::visit(Precision &prec)
  34 {
  35         have_default.insert(prec.type);
  36 }
  37
  38 void DefaultPrecisionGenerator::visit(VariableDeclaration &var)
  39 {
  40         if(var.type_declaration)
  41                 return;
  42
  43         string type = var.type;
  44         if(!type.compare(0, 3, "vec") || !type.compare(0, 3, "mat"))
  45                 type = "float";
  46         else if(!type.compare(0, 3, "ivec") || type=="uint")
  47                 type = "int";
  48
  49         if(!have_default.count(type))
  50         {
  51                 Precision *prec = new Precision;
  52                 if(!type.compare(0, 7, "sampler"))
  53                         prec->precision = "lowp";
  54                 else if(stage->type==Stage::FRAGMENT)
  55                         prec->precision = "mediump";
  56                 else
  57                         prec->precision = "highp";
  58                 prec->type = type;
  59                 stage->content.body.insert(insert_point, prec);
  60
  61                 have_default.insert(type);
  62         }
  63 }
  64
  65
  66 void PrecisionRemover::apply(Stage &stage)
  67 {
  68         stage.content.visit(*this);
  69         NodeRemover().apply(stage, nodes_to_remove);
  70 }
  71
  72 void PrecisionRemover::visit(Precision &prec)
  73 {
  74         nodes_to_remove.insert(&prec);
  75 }
  76
  77 void PrecisionRemover::visit(VariableDeclaration &var)
  78 {
  79         var.precision.clear();
  80 }
  81
  82
  83 LegacyConverter::LegacyConverter():
  84         frag_out(0)
  85 { }
  86
  87 void LegacyConverter::apply(Stage &s, const Features &feat)
  88 {
  89         stage = &s;
  90         features = feat;
  91         if(!supports_stage(s.type))
  92                 throw unsupported_shader(format("Stage %s is not supported", Stage::get_stage_name(s.type)));
  93         s.content.visit(*this);
  94 }
  95
  96 void LegacyConverter::visit(Block &block)
  97 {
  98         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
  99         {
 100                 if(&block==&stage->content)
 101                         uniform_insert_point = i;
 102                 (*i)->visit(*this);
 103         }
 104 }
 105
 106 bool LegacyConverter::check_version(const Version &feature_version) const
 107 {
 108         if(features.glsl_version<feature_version)
 109                 return false;
 110         else if(stage->required_features.glsl_version<feature_version)
 111                 stage->required_features.glsl_version = feature_version;
 112
 113         return true;
 114 }
 115
 116 bool LegacyConverter::check_extension(bool Features::*extension) const
 117 {
 118         if(!(features.*extension))
 119                 return false;
 120
 121         stage->required_features.*extension = true;
 122
 123         return true;
 124 }
 125
 126 bool LegacyConverter::supports_stage(Stage::Type st) const
 127 {
 128         if(st==Stage::GEOMETRY)
 129         {
 130                 if(features.gl_api==OPENGL_ES2)
 131                         return check_version(Version(3, 20));
 132                 else
 133                         return check_version(Version(1, 50));
 134         }
 135         else
 136                 return true;
 137 }
 138
 139 bool LegacyConverter::supports_unified_interface_syntax() const
 140 {
 141         if(features.gl_api==OPENGL_ES2)
 142                 return check_version(Version(3, 0));
 143         else
 144                 return check_version(Version(1, 30));
 145 }
 146
 147 void LegacyConverter::visit(VariableReference &var)
 148 {
 149         if(var.declaration==frag_out && !supports_unified_interface_syntax())
 150         {
 151                 var.name = "gl_FragColor";
 152                 var.declaration = 0;
 153                 type = "vec4";
 154         }
 155         else if(var.declaration)
 156                 type = var.declaration->type;
 157         else
 158                 type = string();
 159 }
 160
 161 void LegacyConverter::visit(Assignment &assign)
 162 {
 163         TraversingVisitor::visit(assign);
 164         if(assign.target_declaration==frag_out && !supports_unified_interface_syntax())
 165                 assign.target_declaration = 0;
 166 }
 167
 168 bool LegacyConverter::supports_unified_sampling_functions() const
 169 {
 170         if(features.gl_api==OPENGL_ES2)
 171                 return check_version(Version(3, 0));
 172         else
 173                 return check_version(Version(1, 30));
 174 }
 175
 176 void LegacyConverter::visit(FunctionCall &call)
 177 {
 178         if(call.name=="texture")
 179         {
 180                 string sampler_type;
 181                 type = string();
 182                 NodeArray<Expression>::iterator i = call.arguments.begin();
 183                 if(i!=call.arguments.end())
 184                 {
 185                         (*i)->visit(*this);
 186                         sampler_type = type;
 187
 188                         for(; i!=call.arguments.end(); ++i)
 189                                 (*i)->visit(*this);
 190                 }
 191
 192                 if(!supports_unified_sampling_functions())
 193                 {
 194                         if(sampler_type=="sampler1D")
 195                                 call.name = "texture1D";
 196                         else if(sampler_type=="sampler2D")
 197                                 call.name = "texture2D";
 198                         else if(sampler_type=="sampler3D")
 199                                 call.name = "texture3D";
 200                         else if(sampler_type=="samplerCube")
 201                                 call.name = "textureCube";
 202                         else if(sampler_type=="sampler1DShadow")
 203                                 call.name = "shadow1D";
 204                         else if(sampler_type=="sampler2DShadow")
 205                                 call.name = "shadow2D";
 206                         else if(sampler_type=="sampler1DArray")
 207                         {
 208                                 check_extension(&Features::ext_texture_array);
 209                                 call.name = "texture1DArray";
 210                         }
 211                         else if(sampler_type=="sampler2DArray")
 212                         {
 213                                 check_extension(&Features::ext_texture_array);
 214                                 call.name = "texture2DArray";
 215                         }
 216                         else if(sampler_type=="sampler1DArrayShadow")
 217                         {
 218                                 check_extension(&Features::ext_texture_array);
 219                                 call.name = "shadow1DArray";
 220                         }
 221                         else if(sampler_type=="sampler2DArrayShadow")
 222                         {
 223                                 check_extension(&Features::ext_texture_array);
 224                                 call.name = "shadow2DArray";
 225                         }
 226                 }
 227         }
 228         else
 229                 TraversingVisitor::visit(call);
 230 }
 231
 232 bool LegacyConverter::supports_interface_layouts() const
 233 {
 234         if(features.gl_api==OPENGL_ES2)
 235                 return check_version(Version(3, 0));
 236         else if(check_version(Version(3, 30)))
 237                 return true;
 238         else
 239                 return check_extension(&Features::arb_explicit_attrib_location);
 240 }
 241
 242 bool LegacyConverter::supports_centroid_sampling() const
 243 {
 244         if(features.gl_api==OPENGL_ES2)
 245                 return check_version(Version(3, 0));
 246         else if(check_version(Version(1, 20)))
 247                 return true;
 248         else
 249                 return check_extension(&Features::ext_gpu_shader4);
 250 }
 251
 252 bool LegacyConverter::supports_sample_sampling() const
 253 {
 254         if(features.gl_api==OPENGL_ES2)
 255                 return check_version(Version(3, 20));
 256         else if(check_version(Version(4, 0)))
 257                 return true;
 258         else
 259                 return check_extension(&Features::arb_gpu_shader5);
 260 }
 261
 262 void LegacyConverter::visit(VariableDeclaration &var)
 263 {
 264         if(var.layout && !supports_interface_layouts())
 265         {
 266                 vector<Layout::Qualifier>::iterator i;
 267                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->name!="location"); ++i) ;
 268                 if(i!=var.layout->qualifiers.end())
 269                 {
 270                         if(stage->type==Stage::VERTEX && var.interface=="in")
 271                         {
 272                                 stage->locations[var.name] = i->value;
 273                                 var.layout->qualifiers.erase(i);
 274                         }
 275                         else if(stage->type==Stage::FRAGMENT && var.interface=="out")
 276                         {
 277                                 if(i->value!=0 && !check_extension(&Features::ext_gpu_shader4))
 278                                         throw unsupported_shader("EXT_gpu_shader4 is required");
 279                                 stage->locations[var.name] = i->value;
 280                                 var.layout->qualifiers.erase(i);
 281                         }
 282
 283                         if(var.layout->qualifiers.empty())
 284                                 var.layout = 0;
 285                 }
 286         }
 287
 288         if(var.sampling=="centroid")
 289         {
 290                 if(!supports_centroid_sampling())
 291                         var.sampling = string();
 292         }
 293         else if(var.sampling=="sample")
 294         {
 295                 if(!supports_sample_sampling())
 296                         var.sampling = string();
 297         }
 298
 299         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
 300         {
 301                 if(stage->type==Stage::FRAGMENT && var.interface=="out")
 302                 {
 303                         frag_out = &var;
 304                         nodes_to_remove.insert(&var);
 305                 }
 306         }
 307
 308         TraversingVisitor::visit(var);
 309 }
 310
 311 bool LegacyConverter::supports_interface_blocks(const string &iface) const
 312 {
 313         if(features.gl_api==OPENGL_ES2)
 314         {
 315                 if(iface=="uniform")
 316                         return check_version(Version(3, 0));
 317                 else
 318                         return check_version(Version(3, 20));
 319         }
 320         else if(check_version(Version(1, 50)))
 321                 return true;
 322         else if(iface=="uniform")
 323                 return check_extension(&Features::arb_uniform_buffer_object);
 324         else
 325                 return false;
 326 }
 327
 328 void LegacyConverter::visit(InterfaceBlock &iface)
 329 {
 330         if(!supports_interface_blocks(iface.interface))
 331         {
 332                 stage->content.body.splice(uniform_insert_point, iface.members.body);
 333                 nodes_to_remove.insert(&iface);
 334         }
 335 }
 336
 337 } // namespace SL
 338 } // namespace GL
 339 } // namespace Msp