source/programbuilder.cpp

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