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                 s.content.visit(*this);
  93         else
  94                 unsupported(format("Stage %s is not supported", Stage::get_stage_name(s.type)));
  95 }
  96
  97 void LegacyConverter::unsupported(const string &reason)
  98 {
  99         Diagnostic diagnostic;
 100         diagnostic.severity = Diagnostic::ERR;
 101         diagnostic.source = GENERATED_SOURCE;
 102         diagnostic.line = 0;
 103         diagnostic.message = reason;
 104         stage->diagnostics.push_back(diagnostic);
 105 }
 106
 107 void LegacyConverter::visit(Block &block)
 108 {
 109         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 110         {
 111                 if(&block==&stage->content)
 112                         uniform_insert_point = i;
 113                 (*i)->visit(*this);
 114         }
 115 }
 116
 117 bool LegacyConverter::check_version(const Version &feature_version) const
 118 {
 119         if(features.glsl_version<feature_version)
 120                 return false;
 121         else if(stage->required_features.glsl_version<feature_version)
 122                 stage->required_features.glsl_version = feature_version;
 123
 124         return true;
 125 }
 126
 127 bool LegacyConverter::check_extension(bool Features::*extension) const
 128 {
 129         if(!(features.*extension))
 130                 return false;
 131
 132         stage->required_features.*extension = true;
 133
 134         return true;
 135 }
 136
 137 bool LegacyConverter::supports_stage(Stage::Type st) const
 138 {
 139         if(st==Stage::GEOMETRY)
 140         {
 141                 if(features.gl_api==OPENGL_ES2)
 142                         return check_version(Version(3, 20));
 143                 else
 144                         return check_version(Version(1, 50));
 145         }
 146         else
 147                 return true;
 148 }
 149
 150 bool LegacyConverter::supports_unified_interface_syntax() const
 151 {
 152         if(features.gl_api==OPENGL_ES2)
 153                 return check_version(Version(3, 0));
 154         else
 155                 return check_version(Version(1, 30));
 156 }
 157
 158 void LegacyConverter::visit(VariableReference &var)
 159 {
 160         if(var.declaration==frag_out && !supports_unified_interface_syntax())
 161         {
 162                 var.name = "gl_FragColor";
 163                 var.declaration = 0;
 164                 r_type = "vec4";
 165         }
 166         else if(var.declaration)
 167                 r_type = var.declaration->type;
 168         else
 169                 r_type.clear();
 170 }
 171
 172 void LegacyConverter::visit(Assignment &assign)
 173 {
 174         TraversingVisitor::visit(assign);
 175         if(assign.target.declaration==frag_out && !supports_unified_interface_syntax())
 176                 assign.target.declaration = 0;
 177 }
 178
 179 bool LegacyConverter::supports_unified_sampling_functions() const
 180 {
 181         if(features.gl_api==OPENGL_ES2)
 182                 return check_version(Version(3, 0));
 183         else
 184                 return check_version(Version(1, 30));
 185 }
 186
 187 void LegacyConverter::visit(FunctionCall &call)
 188 {
 189         if(call.name=="texture")
 190         {
 191                 string sampler_type;
 192                 r_type.clear();
 193                 NodeArray<Expression>::iterator i = call.arguments.begin();
 194                 if(i!=call.arguments.end())
 195                 {
 196                         (*i)->visit(*this);
 197                         sampler_type = r_type;
 198
 199                         for(; i!=call.arguments.end(); ++i)
 200                                 (*i)->visit(*this);
 201                 }
 202
 203                 if(!supports_unified_sampling_functions())
 204                 {
 205                         if(sampler_type=="sampler1D")
 206                                 call.name = "texture1D";
 207                         else if(sampler_type=="sampler2D")
 208                                 call.name = "texture2D";
 209                         else if(sampler_type=="sampler3D")
 210                                 call.name = "texture3D";
 211                         else if(sampler_type=="samplerCube")
 212                                 call.name = "textureCube";
 213                         else if(sampler_type=="sampler1DShadow")
 214                                 call.name = "shadow1D";
 215                         else if(sampler_type=="sampler2DShadow")
 216                                 call.name = "shadow2D";
 217                         else if(sampler_type=="sampler1DArray")
 218                         {
 219                                 check_extension(&Features::ext_texture_array);
 220                                 call.name = "texture1DArray";
 221                         }
 222                         else if(sampler_type=="sampler2DArray")
 223                         {
 224                                 check_extension(&Features::ext_texture_array);
 225                                 call.name = "texture2DArray";
 226                         }
 227                         else if(sampler_type=="sampler1DArrayShadow")
 228                         {
 229                                 check_extension(&Features::ext_texture_array);
 230                                 call.name = "shadow1DArray";
 231                         }
 232                         else if(sampler_type=="sampler2DArrayShadow")
 233                         {
 234                                 check_extension(&Features::ext_texture_array);
 235                                 call.name = "shadow2DArray";
 236                         }
 237                 }
 238         }
 239         else
 240                 TraversingVisitor::visit(call);
 241 }
 242
 243 bool LegacyConverter::supports_interface_layouts() const
 244 {
 245         if(features.gl_api==OPENGL_ES2)
 246                 return check_version(Version(3, 0));
 247         else if(check_version(Version(3, 30)))
 248                 return true;
 249         else
 250                 return check_extension(&Features::arb_explicit_attrib_location);
 251 }
 252
 253 bool LegacyConverter::supports_centroid_sampling() const
 254 {
 255         if(features.gl_api==OPENGL_ES2)
 256                 return check_version(Version(3, 0));
 257         else if(check_version(Version(1, 20)))
 258                 return true;
 259         else
 260                 return check_extension(&Features::ext_gpu_shader4);
 261 }
 262
 263 bool LegacyConverter::supports_sample_sampling() const
 264 {
 265         if(features.gl_api==OPENGL_ES2)
 266                 return check_version(Version(3, 20));
 267         else if(check_version(Version(4, 0)))
 268                 return true;
 269         else
 270                 return check_extension(&Features::arb_gpu_shader5);
 271 }
 272
 273 void LegacyConverter::visit(VariableDeclaration &var)
 274 {
 275         if(var.layout && !supports_interface_layouts())
 276         {
 277                 vector<Layout::Qualifier>::iterator i;
 278                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->name!="location"); ++i) ;
 279                 if(i!=var.layout->qualifiers.end())
 280                 {
 281                         if(stage->type==Stage::VERTEX && var.interface=="in")
 282                         {
 283                                 stage->locations[var.name] = i->value;
 284                                 var.layout->qualifiers.erase(i);
 285                         }
 286                         else if(stage->type==Stage::FRAGMENT && var.interface=="out")
 287                         {
 288                                 if(check_extension(&Features::ext_gpu_shader4))
 289                                         stage->locations[var.name] = i->value;
 290                                 else if(i->value!=0)
 291                                         unsupported("EXT_gpu_shader4 required for multiple fragment shader outputs");
 292                                 var.layout->qualifiers.erase(i);
 293                         }
 294
 295                         if(var.layout->qualifiers.empty())
 296                                 var.layout = 0;
 297                 }
 298         }
 299
 300         if(var.sampling=="centroid")
 301         {
 302                 if(!supports_centroid_sampling())
 303                         var.sampling = string();
 304         }
 305         else if(var.sampling=="sample")
 306         {
 307                 if(!supports_sample_sampling())
 308                         var.sampling = string();
 309         }
 310
 311         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
 312         {
 313                 if(stage->type==Stage::FRAGMENT && var.interface=="out")
 314                 {
 315                         frag_out = &var;
 316                         nodes_to_remove.insert(&var);
 317                 }
 318         }
 319
 320         TraversingVisitor::visit(var);
 321 }
 322
 323 bool LegacyConverter::supports_interface_blocks(const string &iface) const
 324 {
 325         if(features.gl_api==OPENGL_ES2)
 326         {
 327                 if(iface=="uniform")
 328                         return check_version(Version(3, 0));
 329                 else
 330                         return check_version(Version(3, 20));
 331         }
 332         else if(check_version(Version(1, 50)))
 333                 return true;
 334         else if(iface=="uniform")
 335                 return check_extension(&Features::arb_uniform_buffer_object);
 336         else
 337                 return false;
 338 }
 339
 340 void LegacyConverter::visit(InterfaceBlock &iface)
 341 {
 342         if(!supports_interface_blocks(iface.interface) && iface.type_declaration)
 343         {
 344                 if(!iface.instance_name.empty())
 345                         unsupported("ARB_uniform_buffer_object required for interface block instances");
 346                 else if(iface.struct_declaration)
 347                 {
 348                         stage->content.body.splice(uniform_insert_point, iface.struct_declaration->members.body);
 349                         nodes_to_remove.insert(&iface);
 350                         nodes_to_remove.insert(iface.struct_declaration);
 351                 }
 352                 else
 353                         /* If the interface block is an array, it should have an instance
 354                         name too, so this should never be reached */
 355                         throw logic_error("Unexpected interface block configuration");
 356         }
 357 }
 358
 359 } // namespace SL
 360 } // namespace GL
 361 } // namespace Msp