source/programbuilder.cpp

   1 #include <algorithm>
   2 #include <cstring>
   3 #include <set>
   4 #include <msp/gl/extensions/arb_uniform_buffer_object.h>
   5 #include <msp/strings/format.h>
   6 #include <msp/strings/utils.h>
   7 #include "extension.h"
   8 #include "program.h"
   9 #include "programbuilder.h"
  10 #include "shader.h"
  11 #include "vertexformat.h"
  12
  13 using namespace std;
  14
  15 namespace Msp {
  16 namespace GL {
  17
  18 /*
  19 Naming conventions:
  20   n_*        Normalized vector
  21   l_*        Lighting component
  22
  23   obj_*      Object space
  24   eye_*      Eye space
  25   tbn_*      Tangent-Binormal-Normal space
  26   shd_*      Shadow space
  27   env_*      Environment space
  28   *_dir      Direction vector
  29
  30   zzz_*      Wildcard space, resolved by the builder
  31              All wildcard spaces within an expression must match
  32
  33   xxx_yyy_*  Matrix that transforms between yyy to xxx
  34              The vector is on the side of its designated space, result will be
  35              in the other space
  36   *_matrix   A matrix (duh)
  37   *_rmatrix  A mat4 that works with a row vector
  38
  39   rgb_*      Color with rgb components only
  40   color_*    Color with rgba components
  41 */
  42
  43 /* The array is stored in reverse order, so that variables always come after
  44 anything that might need them. */
  45 const ProgramBuilder::VariableDefinition ProgramBuilder::standard_variables[] =
  46 {
  47         { FRAGMENT, "gl_FragColor", "vec4", "frag_color", 0 },
  48         { FRAGMENT, "frag_color", "vec4", "incoming_color", "!f" },
  49         { FRAGMENT, "frag_color", "vec4", "vec4(mix(fog_color.rgb, incoming_color.rgb, fog_value), incoming_color.a)", "f" },
  50         { FRAGMENT, "fog_value", "float", "exp(-fog_coord*fog_density)", 0 },
  51
  52         { FRAGMENT, "incoming_color", "vec4", "basic_color", "!e!l" },
  53         { FRAGMENT, "incoming_color", "vec4", "vec4(rgb_surface, surface_alpha)", "!el" },
  54         { FRAGMENT, "incoming_color", "vec4", "vec4(rgb_surface+rgb_reflection, surface_alpha)", "e" },
  55
  56         { FRAGMENT, "rgb_reflection", "vec3", "reflect_sample.rgb*reflectivity", 0 },
  57         { FRAGMENT, "reflect_sample", "vec4", "textureCube(environment, env_reflect_dir)", 0 },
  58         { FRAGMENT, "env_reflect_dir", "vec3", "env_eye_matrix*eye_reflect_dir", 0 },
  59         { FRAGMENT, "eye_reflect_dir", "vec3", "eye_tbn_matrix*tbn_reflect_dir", "n" },
  60
  61         { FRAGMENT, "rgb_surface", "vec3", "rgb_unlit_surface", "!l" },
  62         { FRAGMENT, "rgb_surface", "vec3", "rgb_lit_surface", "l" },
  63         { FRAGMENT, "rgb_unlit_surface", "vec3", "basic_color.rgb", "!s" },
  64         { FRAGMENT, "rgb_unlit_surface", "vec3", "basic_color.rgb*l_shadow", "s" },
  65         { FRAGMENT, "rgb_lit_surface", "vec3", "rgb_illumination_diffuse", "!m!t" },
  66         { FRAGMENT, "rgb_lit_surface", "vec3", "rgb_illumination_diffuse*diffuse_sample.rgb", "!mt" },
  67         { FRAGMENT, "rgb_lit_surface", "vec3", "rgb_surface_ambient+rgb_surface_diffuse", "m!p" },
  68         { FRAGMENT, "rgb_lit_surface", "vec3", "rgb_surface_ambient+rgb_surface_diffuse+rgb_surface_specular", "mp" },
  69
  70         { FRAGMENT, "surface_alpha", "float", "basic_color.a", "!m" },
  71         { FRAGMENT, "surface_alpha", "float", "basic_color.a", "m!l" },
  72         { FRAGMENT, "surface_alpha", "float", "material.diffuse.a", "ml!t" },
  73         { FRAGMENT, "surface_alpha", "float", "material.diffuse.a*diffuse_sample.a", "mlt" },
  74         { FRAGMENT, "basic_color", "vec4", "vec4(1.0)", "!m!t" },
  75         { FRAGMENT, "basic_color", "vec4", "diffuse_sample", "!mt" },
  76         { FRAGMENT, "basic_color", "vec4", "color", "m!t" },
  77         { FRAGMENT, "basic_color", "vec4", "color*diffuse_sample", "mt" },
  78
  79         { FRAGMENT, "rgb_surface_ambient", "vec3", "rgb_illumination_ambient*material.ambient.rgb", "!t" },
  80         { FRAGMENT, "rgb_surface_ambient", "vec3", "rgb_illumination_ambient*material.ambient.rgb*diffuse_sample.rgb", "t" },
  81         { FRAGMENT, "rgb_illumination_ambient", "vec3", "ambient_color.rgb", "!y" },
  82         { FRAGMENT, "rgb_illumination_ambient", "vec3", "ambient_color.rgb+l_skylight*sky_color.rgb", "y" },
  83         { FRAGMENT, "l_skylight", "float", "dot(n_zzz_normal, zzz_sky_dir)*0.5+0.5", 0 },
  84
  85         { FRAGMENT, "rgb_surface_specular", "vec3", "rgb_illumination_specular*material.specular.rgb", 0 },
  86         { FRAGMENT, "rgb_illumination_specular", "vec3", "rgb_illumination_specular_direct", "!y|e" },
  87         { FRAGMENT, "rgb_illumination_specular", "vec3", "rgb_illumination_specular_direct+l_sky_specular*sky_color.rgb", "y!e" },
  88         { FRAGMENT, "rgb_illumination_specular_direct", "vec3", "rgb_light_specular", "!s" },
  89         { FRAGMENT, "rgb_illumination_specular_direct", "vec3", "rgb_light_specular*l_shadow", "s" },
  90         { FRAGMENT, "rgb_light_specular[i]", "vec3", "l_specular[i]*light_sources[i].specular.rgb", 0 },
  91         { FRAGMENT, "l_sky_specular", "float", "pow((1.0-pow(clamp(dot(zzz_reflect_dir, zzz_sky_dir)-horizon_limit, -1.0, 0.0), 2.0)), material.shininess/2.0)", 0 },
  92         { FRAGMENT, "l_specular[i]", "float", "pow(max(dot(n_zzz_half_vec[i], n_zzz_normal), 0.0), material.shininess)", 0 },
  93
  94         { FRAGMENT, "rgb_surface_diffuse", "vec3", "rgb_illumination_diffuse*material.diffuse.rgb", "!t" },
  95         { FRAGMENT, "rgb_surface_diffuse", "vec3", "rgb_illumination_diffuse*material.diffuse.rgb*diffuse_sample.rgb", "t" },
  96         { FRAGMENT, "rgb_illumination_diffuse", "vec3", "rgb_light_diffuse", "!s" },
  97         { FRAGMENT, "rgb_illumination_diffuse", "vec3", "rgb_light_diffuse*l_shadow", "s" },
  98         { FRAGMENT, "rgb_light_diffuse[i]", "vec3", "l_diffuse[i]*light_sources[i].diffuse.rgb", 0 },
  99         { FRAGMENT, "l_diffuse[i]", "float", "max(dot(n_zzz_normal, n_zzz_light_dir[i]), 0.0)", 0 },
 100
 101         { FRAGMENT, "l_shadow", "float", "mix(1.0, shadow_sample, shadow_darkness)", 0 },
 102         { FRAGMENT, "shadow_sample", "float", "shadow2D(shadow, shd_vertex)", 0 },
 103
 104         { FRAGMENT, "zzz_reflect_dir", "vec3", "reflect(zzz_incident_dir, n_zzz_normal)", 0 },
 105         { FRAGMENT, "n_zzz_half_vec[i]", "vec3", "normalize(zzz_light_dir[i]-zzz_incident_dir)", 0 },
 106         { FRAGMENT, "n_zzz_light_dir[i]", "vec3", "normalize(zzz_light_dir[i])", 0 },
 107         { FRAGMENT, "n_tbn_normal", "vec3", "normal_sample*2.0-1.0", "n" },
 108         { FRAGMENT, "n_eye_normal", "vec3", "normalize(eye_normal)", "!n" },
 109         { FRAGMENT, "normal_sample", "vec3", "texture2D(normalmap, texture_coord).xyz", 0 },
 110         { FRAGMENT, "diffuse_sample", "vec4", "texture2D(diffusemap, texture_coord)", 0 },
 111
 112         { VERTEX, "gl_Position", "vec4", "projection_matrix*eye_vertex", 0 },
 113         { VERTEX, "fog_coord", "float", "-eye_vertex.z", 0 },
 114         { VERTEX, "shd_vertex", "vec3", "(shd_eye_matrix*eye_vertex).xyz", 0 },
 115         { VERTEX, "tbn_sky_dir", "vec3", "eye_sky_dir*eye_tbn_matrix", "n" },
 116         { VERTEX, "tbn_light_dir[i]", "vec3", "eye_light_dir[i]*eye_tbn_matrix", 0 },
 117         { VERTEX, "eye_light_dir[i]", "vec3", "normalize(eye_light_position[i].xyz-eye_vertex.xyz*eye_light_position[i].w)", 0 },
 118         { VERTEX, "eye_light_position[i]", "vec4", "light_sources[i].position", 0 },
 119         { VERTEX, "tbn_incident_dir", "vec3", "eye_incident_dir*eye_tbn_matrix", 0 },
 120         { VERTEX, "eye_incident_dir", "vec3", "normalize(eye_vertex.xyz)", 0 },
 121         { VERTEX, "eye_tbn_matrix", "mat3", "mat3(eye_tangent, eye_binormal, eye_normal)", 0 },
 122         { VERTEX, "eye_vertex", "vec4", "eye_obj_matrix*vertex", 0 },
 123         { VERTEX, "eye_normal", "vec3", "eye_obj_normal_matrix*normal", 0 },
 124         { VERTEX, "eye_tangent", "vec3", "eye_obj_normal_matrix*tangent", 0 },
 125         { VERTEX, "eye_binormal", "vec3", "eye_obj_normal_matrix*binormal", 0 },
 126         { VERTEX, "texture_coord", "vec2", "texcoord.xy", 0 },
 127
 128         { ATTRIBUTE, "vertex", "vec4", "gl_Vertex", 0 },
 129         { ATTRIBUTE, "texcoord", "vec4", "gl_MultiTexCoord0", 0 },
 130         { ATTRIBUTE, "color", "vec4", "gl_Color", 0 },
 131         { ATTRIBUTE, "normal", "vec3", "gl_Normal", 0 },
 132         { ATTRIBUTE, "tangent", "vec3", 0, 0 },
 133         { ATTRIBUTE, "binormal", "vec3", 0, 0 },
 134
 135         { UNIFORM, "diffusemap", "sampler2D", 0, 0 },
 136         { UNIFORM, "shadow", "sampler2DShadow", 0, 0 },
 137         { UNIFORM, "ShadowMap::shadow_darkness", "float", 0, 0 },
 138         { UNIFORM, "normalmap", "sampler2D", 0, 0 },
 139         { UNIFORM, "environment", "samplerCube", 0, 0 },
 140         { UNIFORM, "EnvMap::env_eye_matrix", "mat3", 0, 0 },
 141         { UNIFORM, "Material::reflectivity", "float", 0, 0 },
 142         { UNIFORM, "eye_obj_matrix", "mat4", "gl_ModelViewMatrix", 0 },
 143         { UNIFORM, "eye_obj_normal_matrix", "mat3", "gl_NormalMatrix", 0 },
 144         { UNIFORM, "Transform::projection_matrix", "mat4", "gl_ProjectionMatrix", 0 },
 145         { UNIFORM, "ShadowMap::shd_eye_matrix", "mat4", 0, 0 },
 146         { UNIFORM, "Lighting::light_sources", "LightSourceParameters[MAX_LIGHTS]", "gl_LightSource[i]", 0 },
 147         { UNIFORM, "Lighting::ambient_color", "vec4", "gl_LightModel.ambient", 0 },
 148         { UNIFORM, "Lighting::sky_color", "vec4", 0, 0 },
 149         { UNIFORM, "Lighting::eye_sky_dir", "vec3", 0, 0 },
 150         { UNIFORM, "Lighting::horizon_limit", "float", 0, 0 },
 151         { UNIFORM, "Lighting::fog_color", "vec4", "gl_Fog.color", 0 },
 152         { UNIFORM, "Lighting::fog_density", "float", "gl_Fog.density", 0 },
 153         { UNIFORM, "Material::material", "MaterialParameters", "gl_FrontMaterial", 0 },
 154
 155         { TYPE, "LightSourceParameters", "struct { vec4 position; vec4 diffuse; vec4 specular; }", "gl_LightSourceParameters", 0 },
 156         { TYPE, "MaterialParameters", "struct { vec4 ambient; vec4 diffuse; vec4 specular; float shininess; }", "gl_MaterialParameters", 0 },
 157
 158         // Terminator entry
 159         { NO_SCOPE, 0, 0, 0, 0 }
 160 };
 161
 162 const char ProgramBuilder::interfaces[] = { 0, 0, 0, 0, 'v', 0 };
 163
 164 ProgramBuilder::ProgramBuilder(const StandardFeatures &f):
 165         features(f),
 166         feature_flags(features.create_flags()),
 167         optimize(true)
 168 {
 169         if(!features.custom.empty())
 170         {
 171                 const char *whitespace = " \t\n";
 172                 string::size_type start = 0;
 173                 while(1)
 174                 {
 175                         start = features.custom.find_first_not_of(whitespace, start);
 176                         if(start==string::npos)
 177                                 break;
 178
 179                         string::size_type semicolon = features.custom.find(';', start);
 180                         if(semicolon==start)
 181                         {
 182                                 ++start;
 183                                 continue;
 184                         }
 185                         else if(semicolon==string::npos)
 186                                 throw invalid_variable_definition(features.custom.substr(start));
 187
 188                         string::size_type equals = features.custom.find('=', start);
 189                         if(equals>semicolon)
 190                                 equals = string::npos;
 191
 192                         VariableDefinition var;
 193                         string::size_type decl_end = min(equals, semicolon);
 194                         for(unsigned i=0;; ++i)
 195                         {
 196                                 string::size_type word_end = features.custom.find_first_of(whitespace, start);
 197                                 word_end = min(word_end, decl_end);
 198                                 features.custom[word_end] = 0;
 199
 200                                 const char *word = &features.custom[start];
 201                                 if(i==0)
 202                                 {
 203                                         if(!strcmp(word, "uniform"))
 204                                                 var.scope = UNIFORM;
 205                                         else if(!strcmp(word, "attribute"))
 206                                                 var.scope = ATTRIBUTE;
 207                                         else if(!strcmp(word, "vertex"))
 208                                                 var.scope = VERTEX;
 209                                         else if(!strcmp(word, "fragment"))
 210                                                 var.scope = FRAGMENT;
 211                                         else
 212                                                 throw invalid_variable_definition(word);
 213                                 }
 214                                 else if(i==1)
 215                                         var.type = word;
 216                                 else if(i==2)
 217                                         var.name = word;
 218
 219                                 start = features.custom.find_first_not_of(whitespace, word_end+1);
 220                                 if(start>=decl_end)
 221                                         break;
 222                         }
 223
 224                         if(equals!=string::npos)
 225                         {
 226                                 start = features.custom.find_first_not_of(whitespace, equals+1);
 227                                 if(start>=semicolon)
 228                                         throw invalid_variable_definition("no expression");
 229                                 features.custom[semicolon] = 0;
 230                                 var.expression = &features.custom[start];
 231                         }
 232                         else
 233                                 var.expression = 0;
 234
 235                         var.flags = 0;
 236                         for(const VariableDefinition *j=standard_variables; j->name; ++j)
 237                                 if(!strcmp(var.name, j->name))
 238                                         var.flags = "o";
 239
 240                         custom_variables.push_front(var);
 241
 242                         start = semicolon+1;
 243                 }
 244         }
 245
 246         if(!features.legacy)
 247         {
 248                 aliases["texture1D"] = "texture";
 249                 aliases["texture2D"] = "texture";
 250                 aliases["texture3D"] = "texture";
 251                 aliases["textureCube"] = "texture";
 252                 aliases["shadow2D"] = "texture";
 253         }
 254         else
 255                 aliases["shadow2D"] = "shadow2D(...).r";
 256 }
 257
 258 void ProgramBuilder::set_optimize(bool o)
 259 {
 260         optimize = o;
 261 }
 262
 263 Program *ProgramBuilder::create_program() const
 264 {
 265         Program *prog = new Program;
 266         add_shaders(*prog);
 267         return prog;
 268 }
 269
 270 void ProgramBuilder::add_shaders(Program &prog) const
 271 {
 272         list<ShaderVariable> variables;
 273         list<ShaderVariable *> resolved_vars;
 274
 275         variables.push_front(ShaderVariable("gl_Position"));
 276         variables.push_front(ShaderVariable(features.legacy ? "gl_FragColor" : "frag_color"));
 277
 278         list<VariableDefinition>::const_iterator next_custom = custom_variables.begin();
 279         for(const VariableDefinition *i=standard_variables; i->name; )
 280         {
 281                 const VariableDefinition *def = 0;
 282                 if(next_custom!=custom_variables.end() && (!strcmp(next_custom->name, i->name) || !next_custom->flags))
 283                 {
 284                         def = &*next_custom;
 285                         ++next_custom;
 286                 }
 287                 else
 288                 {
 289                         def = i;
 290                         ++i;
 291
 292                         // Skip over anything that isn't used with the supplied flags
 293                         if(def->flags && !evaluate_flags(def->flags))
 294                                 continue;
 295                 }
 296
 297                 if(def->scope==TYPE)
 298                 {
 299                         for(list<ShaderVariable *>::iterator j=resolved_vars.begin(); j!=resolved_vars.end(); ++j)
 300                                 if(!(*j)->type && name_match(def->name, (*j)->variable->type))
 301                                         (*j)->resolve_type(*def);
 302
 303                         continue;
 304                 }
 305
 306                 const char *def_uq_name = unqualified_name(def->name);
 307
 308                 // See if this variable can satisfy any unresolved variables
 309                 ShaderVariable *last_resolved = 0;
 310                 for(list<ShaderVariable>::iterator j=variables.begin(); j!=variables.end(); ++j)
 311                 {
 312                         if(j->variable)
 313                                 continue;
 314
 315                         if(!name_match(def_uq_name, j->resolved_name.c_str()))
 316                                 continue;
 317
 318                         if(last_resolved)
 319                         {
 320                                 /* We've already resolved a non-fuzzy variable in this iteration.
 321                                 If there are multiple variables that can be resolved, they refer
 322                                 to the same variable. */
 323                                 j->resolve(*last_resolved);
 324                                 continue;
 325                         }
 326
 327                         j->resolve(*def);
 328                         resolved_vars.push_front(&*j);
 329                         if(!j->fuzzy_space)
 330                                 last_resolved = &*j;
 331
 332                         if(!def->expression)
 333                                 continue;
 334
 335                         vector<string> identifiers = extract_identifiers(def->expression);
 336                         for(vector<string>::const_iterator k=identifiers.begin(); k!=identifiers.end(); ++k)
 337                         {
 338                                 // Use an existing variable if possible, but only if it's not fuzzy
 339                                 ShaderVariable *var = 0;
 340                                 for(list<ShaderVariable>::iterator l=variables.begin(); (!var && l!=variables.end()); ++l)
 341                                         if(!l->fuzzy_space && l->resolved_name==*k)
 342                                                 var = &*l;
 343
 344                                 if(!var)
 345                                 {
 346                                         variables.push_back(ShaderVariable(*k));
 347                                         var = &variables.back();
 348                                 }
 349                                 j->add_reference(*var);
 350                         }
 351                 }
 352         }
 353
 354         // Array sizes need to be resolved for inline processing
 355         for(list<ShaderVariable>::iterator i=variables.end(); i!=variables.begin(); )
 356                 (--i)->resolve_array(features);
 357
 358         bool legacy_variables = evaluate_flags("g");
 359         for(list<ShaderVariable *>::const_iterator i=resolved_vars.begin(); i!=resolved_vars.end(); ++i)
 360                 (*i)->check_inline(legacy_variables, !optimize);
 361
 362         prog.attach_shader_owned(new VertexShader(create_source(resolved_vars, VERTEX)));
 363         prog.attach_shader_owned(new FragmentShader(create_source(resolved_vars, FRAGMENT)));
 364
 365         if(!features.legacy)
 366         {
 367                 // OpenGL ES does not support binding fragment shader outputs
 368                 if(get_gl_api()!=OPENGL_ES2)
 369                         prog.bind_fragment_data(0, "frag_color");
 370
 371                 prog.bind_attribute(VERTEX4, "vertex");
 372                 if(features.lighting)
 373                         prog.bind_attribute(NORMAL3, "normal");
 374                 else if(features.material)
 375                         prog.bind_attribute(COLOR4_FLOAT, "color");
 376                 if(features.texture || features.normalmap)
 377                         prog.bind_attribute(TEXCOORD4, "texcoord");
 378         }
 379         if(features.normalmap)
 380         {
 381                 prog.bind_attribute(get_component_type(TANGENT3), "tangent");
 382                 prog.bind_attribute(get_component_type(BINORMAL3), "binormal");
 383         }
 384 }
 385
 386 string ProgramBuilder::create_source(const list<ShaderVariable *> &variables, VariableScope scope) const
 387 {
 388         string source;
 389
 390         bool use_blocks = !features.legacy && ARB_uniform_buffer_object;
 391
 392         if(!features.legacy)
 393         {
 394                 if(get_gl_api()==OPENGL_ES2)
 395                 {
 396                         if(use_blocks)
 397                                 source += "#version 300 es\n";
 398                 }
 399                 else
 400                 {
 401                         source += "#version 130\n";
 402                         if(use_blocks)
 403                                 source += "#extension GL_ARB_uniform_buffer_object: require\n";
 404                 }
 405         }
 406
 407         if(get_gl_api()==OPENGL_ES2)
 408                 source += "precision mediump float;\n";
 409
 410         set<const VariableDefinition *> declared_types;
 411         set<string> uniform_blocks;
 412         for(list<ShaderVariable *>::const_iterator i=variables.begin(); i!=variables.end(); ++i)
 413                 if((*i)->variable->scope==UNIFORM && (*i)->is_referenced_from(scope) && !(*i)->inlined)
 414                 {
 415                         if((*i)->type && !declared_types.count((*i)->type))
 416                         {
 417                                 source += format("%s;\n", (*i)->create_type_declaration());
 418                                 declared_types.insert((*i)->type);
 419                         }
 420
 421                         if(!(*i)->resolved_block.empty() && use_blocks)
 422                                 uniform_blocks.insert((*i)->resolved_block);
 423                         else
 424                                 source += format("uniform %s;\n", (*i)->create_declaration());
 425                 }
 426
 427         for(set<string>::const_iterator i=uniform_blocks.begin(); i!=uniform_blocks.end(); ++i)
 428         {
 429                 source += format("uniform %s\n{\n", *i);
 430                 for(list<ShaderVariable *>::const_iterator j=variables.begin(); j!=variables.end(); ++j)
 431                         if((*j)->resolved_block==*i)
 432                                 source += format("\t%s;\n", (*j)->create_declaration());
 433                 source += "};\n";
 434         }
 435
 436         /* Interface variables need to have global declarations. */
 437         for(list<ShaderVariable *>::const_iterator i=variables.begin(); i!=variables.end(); ++i)
 438         {
 439                 if(!(*i)->resolved_name.compare(0, 3, "gl_"))
 440                         continue;
 441
 442                 InterfaceFlags iface = (*i)->get_interface_flags(scope);
 443
 444                 if(iface&INPUT)
 445                 {
 446                         const char *qualifier = (features.legacy ? scope==VERTEX ? "attribute" : "varying" : "in");
 447                         source += format("%s %s;\n", qualifier, (*i)->create_declaration(interfaces[scope-1]));
 448                 }
 449
 450                 if(iface&OUTPUT)
 451                 {
 452                         const char *qualifier = (features.legacy ? "varying" : "out");
 453                         source += format("%s %s;\n", qualifier, (*i)->create_declaration(interfaces[scope]));
 454                 }
 455         }
 456
 457         source += "void main()\n{\n";
 458
 459         list<ShaderVariable *> loop_vars;
 460         unsigned loop_size = 0;
 461         for(list<ShaderVariable *>::const_iterator i=variables.begin(); i!=variables.end(); ++i)
 462         {
 463                 if(!loop_vars.empty() && !loop_vars.back()->in_loop && (*i)->array_size!=loop_size)
 464                 {
 465                         /* Declare all variables that need to be visible outside the loop.
 466                         Output variables are already declared. */
 467                         for(list<ShaderVariable *>::const_iterator j=loop_vars.begin(); j!=loop_vars.end(); ++j)
 468                         {
 469                                 InterfaceFlags iface = (*j)->get_interface_flags(scope);
 470                                 if(!(*j)->in_loop && !(iface&OUTPUT))
 471                                         source += format("\t%s;\n", (*j)->create_declaration());
 472                         }
 473
 474                         source += format("\tfor(int i=0; i<%d; ++i)\n\t{\n", loop_size);
 475                         for(list<ShaderVariable *>::const_iterator j=loop_vars.begin(); j!=loop_vars.end(); ++j)
 476                         {
 477                                 if((*j)->variable->scope==scope && !(*j)->inlined)
 478                                 {
 479                                         string decl;
 480                                         if((*j)->in_loop)
 481                                                 decl = (*j)->create_declaration(0, true);
 482                                         else
 483                                         {
 484                                                 decl = (*j)->resolved_name;
 485                                                 if(!(*j)->array_sum)
 486                                                         decl += "[i]";
 487                                         }
 488                                         const char *oper = ((*j)->array_sum ? "+=" : "=");
 489                                         source += format("\t\t%s %s %s;\n", decl, oper, create_expression(**j, "i"));
 490                                 }
 491
 492                                 InterfaceFlags iface = (*j)->get_interface_flags(scope);
 493                                 if(iface&OUTPUT)
 494                                 {
 495                                         string expr = ((*j)->inlined ? create_expression(**j, "i") : (*j)->resolved_name+"[i]");
 496                                         source += format("\t\t%c_%s[i] = %s;\n", interfaces[scope], (*j)->resolved_name, expr);
 497                                 }
 498                         }
 499                         source += "\t}\n";
 500
 501                         loop_vars.clear();
 502                 }
 503
 504                 InterfaceFlags iface = (*i)->get_interface_flags(scope);
 505
 506                 if((*i)->array_size>1)
 507                 {
 508                         if((*i)->variable->scope==scope || (iface&OUTPUT))
 509                         {
 510                                 loop_size = (*i)->array_size;
 511                                 loop_vars.push_back(*i);
 512                         }
 513                         continue;
 514                 }
 515
 516                 if((*i)->variable->scope==scope && !(*i)->inlined)
 517                 {
 518                         string decl = ((iface&GOAL) ? (*i)->resolved_name : (*i)->create_declaration());
 519                         source += format("\t%s = %s;\n", decl, create_expression(**i));
 520                 }
 521
 522                 if((iface&(OUTPUT|GOAL))==OUTPUT)
 523                 {
 524                         string expr = ((*i)->inlined ? create_expression(**i) : (*i)->resolved_name);
 525                         source += format("\t%c_%s = %s;\n", interfaces[scope], (*i)->resolved_name, expr);
 526                 }
 527         }
 528
 529         source += '}';
 530
 531         return source;
 532 }
 533
 534 bool ProgramBuilder::evaluate_flags(const char *flags) const
 535 {
 536         if(!flags)
 537                 return true;
 538
 539         bool cond = true;
 540         char oper = '&';
 541         for(const char *i=flags; *i; ++i)
 542         {
 543                 if(*i>='a' && *i<='z')
 544                 {
 545                         bool found = (feature_flags.find(*i)!=string::npos);
 546                         if(oper=='|')
 547                                 cond = (cond || found);
 548                         else if(oper=='!')
 549                                 cond = (cond && !found);
 550                         else if(oper=='&')
 551                                 cond = (cond && found);
 552                         oper = '&';
 553                 }
 554                 else
 555                         oper = *i;
 556         }
 557
 558         return cond;
 559 }
 560
 561 const char *ProgramBuilder::unqualified_name(const char *name)
 562 {
 563         for(const char *p=name; *p; ++p)
 564                 if(*p==':' && *++p==':')
 565                         name = p+1;
 566         return name;
 567 }
 568
 569 ProgramBuilder::MatchType ProgramBuilder::name_match(const char *n1, const char *n2, const char **space)
 570 {
 571         int i = 0;
 572         int zzz = -1;
 573         int zside = 0;
 574         while(*n1 && *n2)
 575         {
 576                 if(*n1==*n2 || *n1=='z' || *n2=='z')
 577                 {
 578                         if(*n1!=*n2)
 579                         {
 580                                 int side = (*n1=='z' ? 1 : 2);
 581                                 if(zzz<0)
 582                                 {
 583                                         zzz = i;
 584                                         zside = side;
 585                                         if(space)
 586                                         {
 587                                                 if(*n1=='z')
 588                                                         *space = n2;
 589                                                 else
 590                                                         *space = n1;
 591                                         }
 592                                 }
 593                                 else if(i>=zzz+3 || side!=zside)
 594                                         return NO_MATCH;
 595                         }
 596                 }
 597                 else
 598                         return NO_MATCH;
 599                 ++n1;
 600                 ++n2;
 601                 ++i;
 602         }
 603         return (!*n1 && !*n2) ? (zzz>=0 ? FUZZY : EXACT) : ((*n1=='[' || *n2=='[') ? ARRAY : NO_MATCH);
 604 }
 605
 606 bool ProgramBuilder::parse_identifier(const char *ptr, unsigned &start, unsigned &length)
 607 {
 608         bool found = false;
 609         bool member = false;
 610         bool subscript = false;
 611         for(const char *i=ptr;; ++i)
 612         {
 613                 if(!found)
 614                 {
 615                         if(!*i)
 616                                 return false;
 617                         if(isalpha(*i) || *i=='_')
 618                         {
 619                                 if(!member)
 620                                 {
 621                                         start = i-ptr;
 622                                         found = true;
 623                                 }
 624                         }
 625                         else if(*i=='.')
 626                                 member = true;
 627                         else
 628                                 member = false;
 629                 }
 630                 else
 631                 {
 632                         if(subscript)
 633                         {
 634                                 if(*i==']')
 635                                 {
 636                                         length = i+1-(ptr+start);
 637                                         return true;
 638                                 }
 639                                 else if(!isalpha(*i) || i>ptr+start+length+1)
 640                                         return true;
 641                         }
 642                         else if(!isalnum(*i) && *i!='_')
 643                         {
 644                                 length = i-(ptr+start);
 645                                 if(*i=='[')
 646                                         subscript = true;
 647                                 else
 648                                         return true;
 649                         }
 650                 }
 651         }
 652 }
 653
 654 vector<string> ProgramBuilder::extract_identifiers(const char *expression)
 655 {
 656         vector<string> result;
 657         const char *ptr = expression;
 658         unsigned start = 0;
 659         unsigned length = 0;
 660         while(parse_identifier(ptr, start, length))
 661         {
 662                 result.push_back(string(ptr+start, length));
 663                 ptr += start+length;
 664         }
 665         return result;
 666 }
 667
 668 string ProgramBuilder::replace_identifiers(const char *expression, const map<string, string> &replace_map, bool with_functions)
 669 {
 670         string result;
 671         const char *ptr = expression;
 672         unsigned start = 0;
 673         unsigned length = 0;
 674         while(parse_identifier(ptr, start, length))
 675         {
 676                 result.append(ptr, start);
 677                 string identifier(ptr+start, length);
 678                 map<string, string>::const_iterator i = replace_map.find(identifier);
 679                 if(i!=replace_map.end())
 680                 {
 681                         if(with_functions && ptr[start+length]=='(')
 682                         {
 683                                 string::size_type lparen = i->second.find('(');
 684                                 string::size_type rparen = i->second.rfind(')');
 685                                 if(lparen!=string::npos && rparen!=string::npos)
 686                                 {
 687                                         unsigned level = 1;
 688                                         unsigned j;
 689                                         for(j=start+length+1; (ptr[j] && level); ++j)
 690                                         {
 691                                                 level += (ptr[j]=='(');
 692                                                 level -= (ptr[j]==')');
 693                                         }
 694
 695                                         if(!level)
 696                                         {
 697                                                 string subexpr(ptr+start+length, ptr+j);
 698                                                 result += i->second.substr(0, lparen);
 699                                                 result += replace_identifiers(subexpr.c_str(), replace_map, with_functions);
 700                                                 result += i->second.substr(rparen+1);
 701                                                 ptr += j;
 702                                                 continue;
 703                                         }
 704                                 }
 705                         }
 706
 707                         result += i->second;
 708                 }
 709                 else
 710                         result += identifier;
 711                 ptr += start+length;
 712         }
 713         result += ptr;
 714         return result;
 715 }
 716
 717 string ProgramBuilder::create_expression(const ShaderVariable &var, const char *loop) const
 718 {
 719         string expr = var.create_expression(loop);
 720         return replace_identifiers(expr.c_str(), aliases, true);
 721 }
 722
 723
 724 ProgramBuilder::StandardFeatures::StandardFeatures():
 725         texture(false),
 726         material(false),
 727         lighting(false),
 728         max_lights(1),
 729         skylight(false),
 730         fog(false),
 731         specular(false),
 732         normalmap(false),
 733         shadow(false),
 734         reflection(false)
 735 {
 736         if(get_gl_api()==OPENGL_ES2)
 737                 legacy = !(get_glsl_version()>=Version(3, 0));
 738         else
 739                 legacy = !(get_glsl_version()>=Version(1, 30));
 740 }
 741
 742 string ProgramBuilder::StandardFeatures::create_flags() const
 743 {
 744         string flags;
 745         if(texture)
 746                 flags += 't';
 747         if(material)
 748                 flags += 'm';
 749         if(lighting)
 750         {
 751                 flags += 'l';
 752                 if(skylight)
 753                         flags += 'y';
 754                 if(specular)
 755                         flags += 'p';
 756                 if(normalmap)
 757                         flags += 'n';
 758         }
 759         if(fog)
 760                 flags += 'f';
 761         if(shadow)
 762                 flags += 's';
 763         if(reflection)
 764                 flags += 'e';
 765         if(legacy && get_gl_api()==OPENGL)
 766                 flags += 'g';
 767
 768         return flags;
 769 }
 770
 771
 772 ProgramBuilder::ShaderVariable::ShaderVariable(const std::string &n):
 773         name(n),
 774         variable(0),
 775         type(0),
 776         resolved_name(n),
 777         fuzzy_space(name.find("zzz")!=string::npos),
 778         array_sum(false),
 779         array_size(0),
 780         inlined(false),
 781         inline_parens(false),
 782         in_loop(false)
 783 {
 784         string::size_type bracket = name.find('[');
 785         if(bracket!=string::npos)
 786                 array_subscript = name.substr(bracket+1, name.size()-bracket-2);
 787 }
 788
 789 void ProgramBuilder::ShaderVariable::resolve(const VariableDefinition &var)
 790 {
 791         variable = &var;
 792         const char *space = 0;
 793         const char *var_uq_name = unqualified_name(variable->name);
 794         MatchType match = name_match(var_uq_name, resolved_name.c_str(), &space);
 795
 796         if(var_uq_name!=variable->name)
 797                 resolved_block.assign(variable->name, var_uq_name-2);
 798
 799         if(match==FUZZY)
 800                 resolve_space(string(space, 3));
 801         else if(match==ARRAY)
 802         {
 803                 if(array_subscript.empty())
 804                         array_sum = true;
 805                 else if(var.scope==UNIFORM)
 806                 {
 807                         const char *bracket = strrchr(variable->type, '[');
 808                         if(bracket)
 809                                 array_subscript = string(bracket+1, strlen(bracket)-2);
 810                 }
 811         }
 812 }
 813
 814 void ProgramBuilder::ShaderVariable::resolve(ShaderVariable &var)
 815 {
 816         for(list<ShaderVariable *>::iterator i=referenced_by.begin(); i!=referenced_by.end(); ++i)
 817                 (*i)->update_reference(*this, var);
 818         var.referenced_by.insert(var.referenced_by.end(), referenced_by.begin(), referenced_by.end());
 819 }
 820
 821 void ProgramBuilder::ShaderVariable::resolve_type(const VariableDefinition &var)
 822 {
 823         type = &var;
 824 }
 825
 826 void ProgramBuilder::ShaderVariable::resolve_space(const string &space)
 827 {
 828         if(fuzzy_space)
 829         {
 830                 resolved_space = space;
 831
 832                 string::size_type zzz = resolved_name.find("zzz");
 833                 resolved_name.replace(zzz, 3, resolved_space);
 834                 fuzzy_space = false;
 835
 836                 // Resolving the space could have affected other variables that use this one
 837                 for(list<ShaderVariable *>::iterator i=referenced_by.begin(); i!=referenced_by.end(); ++i)
 838                         (*i)->resolve_space(space);
 839         }
 840
 841         for(list<ShaderVariable *>::iterator i=referenced_vars.begin(); i!=referenced_vars.end(); ++i)
 842                 if((*i)->fuzzy_space)
 843                         (*i)->resolve_space(space);
 844 }
 845
 846 void ProgramBuilder::ShaderVariable::resolve_array(const StandardFeatures &features, unsigned size_hint)
 847 {
 848         if(array_size)
 849                 return;
 850         if(!array_sum && array_subscript.empty())
 851                 return;
 852
 853         if(!array_subscript.empty())
 854         {
 855                 string::size_type bracket = resolved_name.find('[');
 856                 if(bracket!=string::npos)
 857                         resolved_name = resolved_name.substr(0, bracket);
 858         }
 859
 860         if(variable && variable->scope==UNIFORM)
 861         {
 862                 if(array_subscript=="MAX_LIGHTS")
 863                         array_size = features.max_lights;
 864                 else if(isnumrc(array_subscript))
 865                         array_size = lexical_cast<unsigned>(array_subscript);
 866                 else
 867                         throw invalid_variable_definition("invalid array size");
 868         }
 869
 870         if(!array_size)
 871         {
 872                 for(list<ShaderVariable *>::const_iterator i=referenced_vars.begin(); i!=referenced_vars.end(); ++i)
 873                         if((*i)->array_size)
 874                         {
 875                                 array_size = (*i)->array_size;
 876                                 break;
 877                         }
 878         }
 879
 880         if(!array_size && size_hint)
 881                 array_size = size_hint;
 882
 883         if(array_size)
 884         {
 885                 for(list<ShaderVariable *>::const_iterator i=referenced_vars.begin(); i!=referenced_vars.end(); ++i)
 886                         if(!(*i)->array_subscript.empty() && !(*i)->array_size)
 887                                 (*i)->resolve_array(features, array_size);
 888         }
 889 }
 890
 891 void ProgramBuilder::ShaderVariable::add_reference(ShaderVariable &var)
 892 {
 893         referenced_vars.push_back(&var);
 894         var.referenced_by.push_back(this);
 895         if(var.fuzzy_space && !resolved_space.empty())
 896                 var.resolve_space(resolved_space);
 897 }
 898
 899 void ProgramBuilder::ShaderVariable::update_reference(ShaderVariable &from, ShaderVariable &to)
 900 {
 901         replace(referenced_vars.begin(), referenced_vars.end(), &from, &to);
 902         replace(referenced_by.begin(), referenced_by.end(), &from, &to);
 903         if(from.fuzzy_space && !to.fuzzy_space && !to.resolved_space.empty())
 904                 resolve_space(to.resolved_space);
 905 }
 906
 907 void ProgramBuilder::ShaderVariable::check_inline(bool allow_legacy, bool trivial_only)
 908 {
 909         if(variable->expression)
 910         {
 911                 if(array_sum && array_size>1)
 912                         return;
 913                 if(!allow_legacy && !strncmp(variable->expression, "gl_", 3))
 914                         return;
 915
 916                 // Never inline goal variables
 917                 if(referenced_by.empty())
 918                         return;
 919
 920                 // Inline an expression consisting of a single identifier
 921                 unsigned start, length;
 922                 if(parse_identifier(variable->expression, start, length))
 923                         if(start==0 && variable->expression[length]==0)
 924                         {
 925                                 inlined = true;
 926                                 return;
 927                         }
 928
 929                 if(trivial_only)
 930                         return;
 931
 932                 /* If all references to the variable come from arrays in the same scope
 933                 and of the same size, the variable can be embedded in the loop. */
 934                 in_loop = (array_size>1 && !array_sum);
 935                 for(list<ShaderVariable *>::const_iterator i=referenced_by.begin(); i!=referenced_by.end(); ++i)
 936                         if((*i)->variable->scope!=variable->scope || (*i)->array_size!=array_size)
 937                                 in_loop = false;
 938
 939                 /* Count all refs to this variable.  Refs from array variables count once
 940                 per loop iteration. */
 941                 unsigned total_refs = 0;
 942                 unsigned in_scope_refs = 0;
 943                 for(list<ShaderVariable *>::const_iterator i=referenced_by.begin(); i!=referenced_by.end(); ++i)
 944                 {
 945                         unsigned count = max((*i)->array_size*!in_loop, 1U);
 946                         total_refs += count;
 947                         if((*i)->variable->scope==variable->scope)
 948                                 in_scope_refs += count;
 949                 }
 950
 951                 /* Inline if there's only one ref, or if all refs are in other scopes.
 952                 In the latter case, the actual inlining will happen in the interface
 953                 variable assignment. */
 954                 if(total_refs==1 || in_scope_refs==0)
 955                 {
 956                         inlined = true;
 957                         unsigned level = 0;
 958                         for(const char *c=variable->expression; (!inline_parens && *c); ++c)
 959                         {
 960                                 if(*c=='(')
 961                                         ++level;
 962                                 else if(*c==')')
 963                                         --level;
 964                                 else if(level==0 && !isalnum(*c) && *c!='_' && *c!='.')
 965                                         inline_parens = true;
 966                         }
 967                 }
 968         }
 969 }
 970
 971 bool ProgramBuilder::ShaderVariable::is_referenced_from(VariableScope scope) const
 972 {
 973         for(list<ShaderVariable *>::const_iterator i=referenced_by.begin(); i!=referenced_by.end(); ++i)
 974                 if((*i)->variable->scope==scope)
 975                         return true;
 976         return false;
 977 }
 978
 979 ProgramBuilder::InterfaceFlags ProgramBuilder::ShaderVariable::get_interface_flags(VariableScope scope) const
 980 {
 981         /* Uniforms are available to all stages and are not passed through
 982         interfaces */
 983         if(variable->scope==UNIFORM)
 984                 return NO_INTERFACE;
 985
 986         int flags = NO_INTERFACE;
 987
 988         for(list<ShaderVariable *>::const_iterator i=referenced_by.begin(); i!=referenced_by.end(); ++i)
 989         {
 990                 /* Variables used in a later scope than they are declared in need to go
 991                 through the interface */
 992                 if((*i)->variable->scope>scope && variable->scope<=scope)
 993                         flags |= OUTPUT;
 994                 if((*i)->variable->scope>=scope && variable->scope<scope)
 995                         if(!inlined || variable->scope!=ATTRIBUTE || scope!=VERTEX)
 996                                 flags |= INPUT;
 997         }
 998
 999         // Variables without any references are goals and also outputs.
1000         if(referenced_by.empty() && variable->scope==scope)
1001                 flags |= OUTPUT|GOAL;
1002
1003         return static_cast<InterfaceFlags>(flags);
1004 }
1005
1006 string ProgramBuilder::ShaderVariable::create_type_declaration() const
1007 {
1008         if(!type)
1009                 throw logic_error("no type");
1010
1011         if(!strncmp(type->type, "struct", 6))
1012         {
1013                 const char *brace = strchr(type->type, '{');
1014                 if(brace)
1015                         return format("struct %s %s", type->name, brace);
1016         }
1017
1018         throw invalid_variable_definition("invalid typedef");
1019 }
1020
1021 string ProgramBuilder::ShaderVariable::create_declaration(char iface, bool loop) const
1022 {
1023         if(variable->scope==UNIFORM && !array_subscript.empty())
1024         {
1025                 const char *bracket = strrchr(variable->type, '[');
1026                 if(bracket)
1027                         return format("%s %s[%d]", string(variable->type, bracket), resolved_name, array_size);
1028         }
1029
1030         string array;
1031         if(!array_sum && array_size>1 && !loop)
1032                 array = format("[%d]", array_size);
1033
1034         if(iface)
1035                 return format("%s %c_%s%s", variable->type, iface, resolved_name, array);
1036         else
1037                 return format("%s %s%s", variable->type, resolved_name, array);
1038 }
1039
1040 string ProgramBuilder::ShaderVariable::create_replacement(VariableScope from_scope, const char *loop) const
1041 {
1042         string replacement = resolved_name;
1043         InterfaceFlags iface = NO_INTERFACE;
1044         if(variable)
1045         {
1046                 iface = get_interface_flags(from_scope);
1047                 if((iface&INPUT) && interfaces[from_scope-1])
1048                         replacement = format("%c_%s", interfaces[from_scope-1], replacement);
1049                 else if(inlined)
1050                 {
1051                         replacement = create_expression(loop);
1052                         if(inline_parens)
1053                                 replacement = "("+replacement+")";
1054                         return replacement;
1055                 }
1056         }
1057
1058         // Add an array subscript, unless the variable is embedded in a loop
1059         if(!array_subscript.empty() && !in_loop)
1060         {
1061                 if(loop)
1062                         return format("%s[%s]", replacement, loop);
1063                 else if(!variable || variable->scope==UNIFORM)
1064                         return replacement+"[0]";
1065         }
1066
1067         return replacement;
1068 }
1069
1070 string ProgramBuilder::ShaderVariable::create_expression(const char *loop) const
1071 {
1072         map<string, string> replace_map;
1073         for(list<ShaderVariable *>::const_iterator i=referenced_vars.begin(); i!=referenced_vars.end(); ++i)
1074         {
1075                 string replacement = (*i)->create_replacement(variable->scope, loop);
1076                 if(replacement!=(*i)->name)
1077                         replace_map[(*i)->name] = replacement;
1078         }
1079
1080         if(replace_map.empty())
1081                 return variable->expression;
1082         else
1083                 return replace_identifiers(variable->expression, replace_map);
1084 }
1085
1086
1087 ProgramBuilder::StandardFeatures::Loader::Loader(StandardFeatures &f):
1088         DataFile::ObjectLoader<StandardFeatures>(f)
1089 {
1090         add("custom",    &StandardFeatures::custom);
1091         add("fog",       &StandardFeatures::fog);
1092         add("lighting",  &StandardFeatures::lighting);
1093         add("material",  &StandardFeatures::material);
1094         add("max_lights", &StandardFeatures::max_lights);
1095         add("normalmap", &StandardFeatures::normalmap);
1096         add("reflection", &StandardFeatures::reflection);
1097         add("shadow",    &StandardFeatures::shadow);
1098         add("skylight",  &StandardFeatures::skylight);
1099         add("specular",  &StandardFeatures::specular);
1100         add("texture",   &StandardFeatures::texture);
1101 }
1102
1103 } // namespace GL
1104 } // namespace Msp