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