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