simgear/scene/material/Effect.cxx

   1 // Copyright (C) 2008 - 2009  Tim Moore timoore@redhat.com
   2 //
   3 // This library is free software; you can redistribute it and/or
   4 // modify it under the terms of the GNU Library General Public
   5 // License as published by the Free Software Foundation; either
   6 // version 2 of the License, or (at your option) any later version.
   7 //
   8 // This library is distributed in the hope that it will be useful,
   9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 // Library General Public License for more details.
  12 //
  13 // You should have received a copy of the GNU General Public License
  14 // along with this program; if not, write to the Free Software
  15 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  16
  17 #ifdef HAVE_CONFIG_H
  18 #  include <simgear_config.h>
  19 #endif
  20
  21 #include "Effect.hxx"
  22 #include "EffectBuilder.hxx"
  23 #include "Technique.hxx"
  24 #include "Pass.hxx"
  25 #include "TextureBuilder.hxx"
  26
  27 #include <algorithm>
  28 #include <functional>
  29 #include <iterator>
  30 #include <map>
  31 #include <utility>
  32
  33 #include <boost/bind.hpp>
  34 #include <boost/foreach.hpp>
  35 #include <boost/lexical_cast.hpp>
  36 #include <boost/tuple/tuple.hpp>
  37 #include <boost/tuple/tuple_comparison.hpp>
  38
  39 #include <osg/CullFace>
  40 #include <osg/Drawable>
  41 #include <osg/Material>
  42 #include <osg/PolygonMode>
  43 #include <osg/Program>
  44 #include <osg/Referenced>
  45 #include <osg/RenderInfo>
  46 #include <osg/ShadeModel>
  47 #include <osg/StateSet>
  48 #include <osg/TexEnv>
  49 #include <osg/Texture1D>
  50 #include <osg/Texture2D>
  51 #include <osg/Texture3D>
  52 #include <osg/TextureRectangle>
  53 #include <osg/Uniform>
  54 #include <osg/Vec4d>
  55 #include <osgUtil/CullVisitor>
  56 #include <osgDB/FileUtils>
  57 #include <osgDB/Input>
  58 #include <osgDB/ParameterOutput>
  59 #include <osgDB/ReadFile>
  60 #include <osgDB/Registry>
  61
  62 #include <simgear/scene/tgdb/userdata.hxx>
  63 #include <simgear/scene/util/SGSceneFeatures.hxx>
  64 #include <simgear/scene/util/StateAttributeFactory.hxx>
  65 #include <simgear/structure/OSGUtils.hxx>
  66 #include <simgear/structure/SGExpression.hxx>
  67
  68
  69
  70 namespace simgear
  71 {
  72 using namespace std;
  73 using namespace osg;
  74 using namespace osgUtil;
  75
  76 Effect::Effect()
  77 {
  78 }
  79
  80 Effect::Effect(const Effect& rhs, const CopyOp& copyop)
  81     : root(rhs.root), parametersProp(rhs.parametersProp)
  82 {
  83     using namespace boost;
  84     transform(rhs.techniques.begin(), rhs.techniques.end(),
  85               back_inserter(techniques),
  86               bind(simgear::clone_ref<Technique>, _1, copyop));
  87 }
  88
  89 // Assume that the last technique is always valid.
  90 StateSet* Effect::getDefaultStateSet()
  91 {
  92     Technique* tniq = techniques.back().get();
  93     if (!tniq)
  94         return 0;
  95     Pass* pass = tniq->passes.front().get();
  96     return pass;
  97 }
  98
  99 // There should always be a valid technique in an effect.
 100
 101 Technique* Effect::chooseTechnique(RenderInfo* info)
 102 {
 103     BOOST_FOREACH(ref_ptr<Technique>& technique, techniques)
 104     {
 105         if (technique->valid(info) == Technique::VALID)
 106             return technique.get();
 107     }
 108     return 0;
 109 }
 110
 111 void Effect::resizeGLObjectBuffers(unsigned int maxSize)
 112 {
 113     BOOST_FOREACH(const ref_ptr<Technique>& technique, techniques)
 114     {
 115         technique->resizeGLObjectBuffers(maxSize);
 116     }
 117 }
 118
 119 void Effect::releaseGLObjects(osg::State* state) const
 120 {
 121     BOOST_FOREACH(const ref_ptr<Technique>& technique, techniques)
 122     {
 123         technique->releaseGLObjects(state);
 124     }
 125 }
 126
 127 Effect::~Effect()
 128 {
 129 }
 130
 131 class PassAttributeBuilder : public Referenced
 132 {
 133 public:
 134     virtual void buildAttribute(Effect* effect, Pass* pass,
 135                                 const SGPropertyNode* prop,
 136                                 const osgDB::ReaderWriter::Options* options)
 137     = 0;
 138 };
 139
 140 typedef map<const string, ref_ptr<PassAttributeBuilder> > PassAttrMap;
 141 PassAttrMap passAttrMap;
 142
 143 template<typename T>
 144 struct InstallAttributeBuilder
 145 {
 146     InstallAttributeBuilder(const string& name)
 147     {
 148         passAttrMap.insert(make_pair(name, new T));
 149     }
 150 };
 151
 152 void buildPass(Effect* effect, Technique* tniq, const SGPropertyNode* prop,
 153                const osgDB::ReaderWriter::Options* options)
 154 {
 155     Pass* pass = new Pass;
 156     tniq->passes.push_back(pass);
 157     for (int i = 0; i < prop->nChildren(); ++i) {
 158         const SGPropertyNode* attrProp = prop->getChild(i);
 159         PassAttrMap::iterator itr = passAttrMap.find(attrProp->getName());
 160         if (itr != passAttrMap.end())
 161             itr->second->buildAttribute(effect, pass, attrProp, options);
 162         else
 163             SG_LOG(SG_INPUT, SG_ALERT,
 164                    "skipping unknown pass attribute " << attrProp->getName());
 165     }
 166 }
 167
 168 osg::Vec4f getColor(const SGPropertyNode* prop)
 169 {
 170     if (prop->nChildren() == 0) {
 171         if (prop->getType() == props::VEC4D) {
 172             return osg::Vec4f(toOsg(prop->getValue<SGVec4d>()));
 173         } else if (prop->getType() == props::VEC3D) {
 174             return osg::Vec4f(toOsg(prop->getValue<SGVec3d>()), 1.0f);
 175         } else {
 176             SG_LOG(SG_INPUT, SG_ALERT,
 177                    "invalid color property " << prop->getName() << " "
 178                    << prop->getStringValue());
 179             return osg::Vec4f(0.0f, 0.0f, 0.0f, 1.0f);
 180         }
 181     } else {
 182         osg::Vec4f result;
 183         static const char* colors[] = {"r", "g", "b"};
 184         for (int i = 0; i < 3; ++i) {
 185             const SGPropertyNode* componentProp = prop->getChild(colors[i]);
 186             result[i] = componentProp ? componentProp->getValue<float>() : 0.0f;
 187         }
 188         const SGPropertyNode* alphaProp = prop->getChild("a");
 189         result[3] = alphaProp ? alphaProp->getValue<float>() : 1.0f;
 190         return result;
 191     }
 192 }
 193
 194 struct LightingBuilder : public PassAttributeBuilder
 195 {
 196     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 197                         const osgDB::ReaderWriter::Options* options);
 198 };
 199
 200 void LightingBuilder::buildAttribute(Effect* effect, Pass* pass,
 201                                      const SGPropertyNode* prop,
 202                                      const osgDB::ReaderWriter::Options* options)
 203 {
 204     const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 205     if (!realProp)
 206         return;
 207     pass->setMode(GL_LIGHTING, (realProp->getValue<bool>() ? StateAttribute::ON
 208                                 : StateAttribute::OFF));
 209 }
 210
 211 InstallAttributeBuilder<LightingBuilder> installLighting("lighting");
 212
 213 struct ShadeModelBuilder : public PassAttributeBuilder
 214 {
 215     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 216                         const osgDB::ReaderWriter::Options* options)
 217     {
 218         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 219         if (!realProp)
 220             return;
 221         StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 222         string propVal = realProp->getStringValue();
 223         if (propVal == "flat")
 224             pass->setAttribute(attrFact->getFlatShadeModel());
 225         else if (propVal == "smooth")
 226             pass->setAttribute(attrFact->getSmoothShadeModel());
 227         else
 228             SG_LOG(SG_INPUT, SG_ALERT,
 229                    "invalid shade model property " << propVal);
 230     }
 231 };
 232
 233 InstallAttributeBuilder<ShadeModelBuilder> installShadeModel("shade-model");
 234
 235 struct CullFaceBuilder : PassAttributeBuilder
 236 {
 237     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 238                         const osgDB::ReaderWriter::Options* options)
 239     {
 240         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 241         if (!realProp)
 242             return;
 243         StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 244         string propVal = realProp->getStringValue();
 245         if (propVal == "front")
 246             pass->setAttributeAndModes(attrFact->getCullFaceFront());
 247         else if (propVal == "back")
 248             pass->setAttributeAndModes(attrFact->getCullFaceBack());
 249         else if (propVal == "front-back")
 250             pass->setAttributeAndModes(new CullFace(CullFace::FRONT_AND_BACK));
 251         else
 252             SG_LOG(SG_INPUT, SG_ALERT,
 253                    "invalid cull face property " << propVal);
 254     }
 255 };
 256
 257 InstallAttributeBuilder<CullFaceBuilder> installCullFace("cull-face");
 258
 259 struct HintBuilder : public PassAttributeBuilder
 260 {
 261     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 262                         const osgDB::ReaderWriter::Options* options)
 263     {
 264         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 265         if (!realProp)
 266             return;
 267         string propVal = realProp->getStringValue();
 268         if (propVal == "opaque")
 269             pass->setRenderingHint(StateSet::OPAQUE_BIN);
 270         else if (propVal == "transparent")
 271             pass->setRenderingHint(StateSet::TRANSPARENT_BIN);
 272     }
 273 };
 274
 275 InstallAttributeBuilder<HintBuilder> installHint("rendering-hint");
 276
 277 struct RenderBinBuilder : public PassAttributeBuilder
 278 {
 279     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 280                         const osgDB::ReaderWriter::Options* options)
 281     {
 282         const SGPropertyNode* binProp = prop->getChild("bin-number");
 283         binProp = getEffectPropertyNode(effect, binProp);
 284         const SGPropertyNode* nameProp = prop->getChild("bin-name");
 285         nameProp = getEffectPropertyNode(effect, nameProp);
 286         if (binProp && nameProp) {
 287             pass->setRenderBinDetails(binProp->getIntValue(),
 288                                       nameProp->getStringValue());
 289         } else {
 290             if (!binProp)
 291                 SG_LOG(SG_INPUT, SG_ALERT,
 292                        "No render bin number specified in render bin section");
 293             if (!nameProp)
 294                 SG_LOG(SG_INPUT, SG_ALERT,
 295                        "No render bin name specified in render bin section");
 296         }
 297     }
 298 };
 299
 300 InstallAttributeBuilder<RenderBinBuilder> installRenderBin("render-bin");
 301
 302 struct MaterialBuilder : public PassAttributeBuilder
 303 {
 304     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 305                         const osgDB::ReaderWriter::Options* options);
 306 };
 307
 308 EffectNameValue<Material::ColorMode> colorModes[] =
 309 {
 310     { "ambient", Material::AMBIENT },
 311     { "ambient-and-diffuse", Material::AMBIENT_AND_DIFFUSE },
 312     { "diffuse", Material::DIFFUSE },
 313     { "emissive", Material::EMISSION },
 314     { "specular", Material::SPECULAR },
 315     { "off", Material::OFF }
 316 };
 317
 318 void MaterialBuilder::buildAttribute(Effect* effect, Pass* pass,
 319                                      const SGPropertyNode* prop,
 320                                      const osgDB::ReaderWriter::Options* options)
 321 {
 322     Material* mat = new Material;
 323     const SGPropertyNode* color = 0;
 324     if ((color = getEffectPropertyChild(effect, prop, "ambient")))
 325         mat->setAmbient(Material::FRONT_AND_BACK, getColor(color));
 326     if ((color = getEffectPropertyChild(effect, prop, "ambient-front")))
 327         mat->setAmbient(Material::FRONT, getColor(color));
 328     if ((color = getEffectPropertyChild(effect, prop, "ambient-back")))
 329         mat->setAmbient(Material::BACK, getColor(color));
 330     if ((color = getEffectPropertyChild(effect, prop, "diffuse")))
 331         mat->setDiffuse(Material::FRONT_AND_BACK, getColor(color));
 332     if ((color = getEffectPropertyChild(effect, prop, "diffuse-front")))
 333         mat->setDiffuse(Material::FRONT, getColor(color));
 334     if ((color = getEffectPropertyChild(effect, prop, "diffuse-back")))
 335         mat->setDiffuse(Material::BACK, getColor(color));
 336     if ((color = getEffectPropertyChild(effect, prop, "specular")))
 337         mat->setSpecular(Material::FRONT_AND_BACK, getColor(color));
 338     if ((color = getEffectPropertyChild(effect, prop, "specular-front")))
 339         mat->setSpecular(Material::FRONT, getColor(color));
 340     if ((color = getEffectPropertyChild(effect, prop, "specular-back")))
 341         mat->setSpecular(Material::BACK, getColor(color));
 342     if ((color = getEffectPropertyChild(effect, prop, "emissive")))
 343         mat->setEmission(Material::FRONT_AND_BACK, getColor(color));
 344     if ((color = getEffectPropertyChild(effect, prop, "emissive-front")))
 345         mat->setEmission(Material::FRONT, getColor(color));
 346     if ((color = getEffectPropertyChild(effect, prop, "emissive-back")))
 347         mat->setEmission(Material::BACK, getColor(color));
 348     const SGPropertyNode* shininess = 0;
 349     mat->setShininess(Material::FRONT_AND_BACK, 0.0f);
 350     if ((shininess = getEffectPropertyChild(effect, prop, "shininess")))
 351         mat->setShininess(Material::FRONT_AND_BACK, shininess->getFloatValue());
 352     if ((shininess = getEffectPropertyChild(effect, prop, "shininess-front")))
 353         mat->setShininess(Material::FRONT, shininess->getFloatValue());
 354     if ((shininess = getEffectPropertyChild(effect, prop, "shininess-back")))
 355         mat->setShininess(Material::BACK, shininess->getFloatValue());
 356     Material::ColorMode colorMode = Material::OFF;
 357     findAttr(colorModes, getEffectPropertyChild(effect, prop, "color-mode"),
 358              colorMode);
 359     mat->setColorMode(colorMode);
 360     pass->setAttribute(mat);
 361 }
 362
 363 InstallAttributeBuilder<MaterialBuilder> installMaterial("material");
 364
 365 struct BlendBuilder : public PassAttributeBuilder
 366 {
 367     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 368                         const osgDB::ReaderWriter::Options* options)
 369     {
 370         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 371         if (!realProp)
 372             return;
 373         pass->setMode(GL_BLEND, (realProp->getBoolValue()
 374                                  ? StateAttribute::ON
 375                                  : StateAttribute::OFF));
 376     }
 377 };
 378
 379 InstallAttributeBuilder<BlendBuilder> installBlend("blend");
 380
 381 struct AlphaTestBuilder : public PassAttributeBuilder
 382 {
 383     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 384                         const osgDB::ReaderWriter::Options* options)
 385     {
 386         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 387         if (!realProp)
 388             return;
 389         pass->setMode(GL_ALPHA_TEST, (realProp->getBoolValue()
 390                                       ? StateAttribute::ON
 391                                       : StateAttribute::OFF));
 392     }
 393 };
 394
 395 InstallAttributeBuilder<AlphaTestBuilder> installAlphaTest("alpha-test");
 396
 397 EffectNameValue<TexEnv::Mode> texEnvModes[] =
 398 {
 399     {"add", TexEnv::ADD},
 400     {"blend", TexEnv::BLEND},
 401     {"decal", TexEnv::DECAL},
 402     {"modulate", TexEnv::MODULATE},
 403     {"replace", TexEnv::REPLACE}
 404 };
 405
 406 TexEnv* buildTexEnv(Effect* effect, const SGPropertyNode* prop)
 407 {
 408     const SGPropertyNode* modeProp = getEffectPropertyChild(effect, prop,
 409                                                             "mode");
 410     const SGPropertyNode* colorProp = getEffectPropertyChild(effect, prop,
 411                                                              "color");
 412     if (!modeProp)
 413         return 0;
 414     TexEnv::Mode mode = TexEnv::MODULATE;
 415     findAttr(texEnvModes, modeProp, mode);
 416     if (mode == TexEnv::MODULATE) {
 417         return StateAttributeFactory::instance()->getStandardTexEnv();
 418     }
 419     TexEnv* env = new TexEnv(mode);
 420     if (colorProp)
 421         env->setColor(toOsg(colorProp->getValue<SGVec4d>()));
 422     return env;
 423  }
 424
 425
 426 struct TextureUnitBuilder : PassAttributeBuilder
 427 {
 428     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 429                         const osgDB::ReaderWriter::Options* options);
 430 };
 431
 432 void TextureUnitBuilder::buildAttribute(Effect* effect, Pass* pass,
 433                                         const SGPropertyNode* prop,
 434                                         const osgDB::ReaderWriter::Options* options)
 435 {
 436
 437     // Decode the texture unit
 438     int unit = 0;
 439     const SGPropertyNode* pUnit = prop->getChild("unit");
 440     if (pUnit) {
 441         unit = pUnit->getValue<int>();
 442     } else {
 443         const SGPropertyNode* pName = prop->getChild("name");
 444         if (pName)
 445             try {
 446                 unit = boost::lexical_cast<int>(pName->getStringValue());
 447             } catch (boost::bad_lexical_cast& lex) {
 448                 SG_LOG(SG_INPUT, SG_ALERT, "can't decode name as texture unit "
 449                        << lex.what());
 450             }
 451     }
 452     const SGPropertyNode* pType = prop->getChild("type");
 453     string type;
 454     if (!pType)
 455         type = "2d";
 456     else
 457         type = pType->getStringValue();
 458     Texture* texture = 0;
 459     try {
 460         texture = TextureBuilder::buildFromType(effect, type, prop,
 461                                                 options);
 462     }
 463     catch (BuilderException& e) {
 464         SG_LOG(SG_INPUT, SG_ALERT, "No image file for texture, using white ");
 465         texture = StateAttributeFactory::instance()->getWhiteTexture();
 466     }
 467     pass->setTextureAttributeAndModes(unit, texture);
 468     const SGPropertyNode* envProp = prop->getChild("environment");
 469     if (envProp) {
 470         TexEnv* env = buildTexEnv(effect, envProp);
 471         if (env)
 472             pass->setTextureAttributeAndModes(unit, env);
 473     }
 474 }
 475
 476
 477
 478 InstallAttributeBuilder<TextureUnitBuilder> textureUnitBuilder("texture-unit");
 479
 480 typedef map<string, ref_ptr<Program> > ProgramMap;
 481 ProgramMap programMap;
 482
 483 typedef map<string, ref_ptr<Shader> > ShaderMap;
 484 ShaderMap shaderMap;
 485
 486 void reload_shaders()
 487 {
 488     for(ShaderMap::iterator sitr = shaderMap.begin(); sitr != shaderMap.end(); ++sitr)
 489     {
 490         Shader *shader = sitr->second.get();
 491         string fileName = osgDB::findDataFile(sitr->first);
 492         if (!fileName.empty()) {
 493             shader->loadShaderSourceFromFile(fileName);
 494         }
 495     }
 496 }
 497
 498 struct ShaderProgramBuilder : PassAttributeBuilder
 499 {
 500     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 501                         const osgDB::ReaderWriter::Options* options);
 502 };
 503
 504 void ShaderProgramBuilder::buildAttribute(Effect* effect, Pass* pass,
 505                                           const SGPropertyNode* prop,
 506                                           const osgDB::ReaderWriter::Options*
 507                                           options)
 508 {
 509     PropertyList pVertShaders = prop->getChildren("vertex-shader");
 510     PropertyList pFragShaders = prop->getChildren("fragment-shader");
 511     string programKey;
 512     for (PropertyList::iterator itr = pVertShaders.begin(),
 513              e = pVertShaders.end();
 514          itr != e;
 515          ++itr)
 516     {
 517         programKey += (*itr)->getStringValue();
 518         programKey += ";";
 519     }
 520     for (PropertyList::iterator itr = pFragShaders.begin(),
 521              e = pFragShaders.end();
 522          itr != e;
 523          ++itr)
 524     {
 525         programKey += (*itr)->getStringValue();
 526         programKey += ";";
 527     }
 528     Program* program = 0;
 529     ProgramMap::iterator pitr = programMap.find(programKey);
 530     if (pitr != programMap.end()) {
 531         program = pitr->second.get();
 532     } else {
 533         program = new Program;
 534         program->setName(programKey);
 535         // Add vertex shaders, then fragment shaders
 536         PropertyList& pvec = pVertShaders;
 537         Shader::Type stype = Shader::VERTEX;
 538         for (int i = 0; i < 2; ++i) {
 539             for (PropertyList::iterator nameItr = pvec.begin(), e = pvec.end();
 540                  nameItr != e;
 541                  ++nameItr) {
 542                 string shaderName = (*nameItr)->getStringValue();
 543                 ShaderMap::iterator sitr = shaderMap.find(shaderName);
 544                 if (sitr != shaderMap.end()) {
 545                     program->addShader(sitr->second.get());
 546                 } else {
 547                     string fileName = osgDB::findDataFile(shaderName, options);
 548                     if (!fileName.empty()) {
 549                         ref_ptr<Shader> shader = new Shader(stype);
 550                         if (shader->loadShaderSourceFromFile(fileName)) {
 551                             program->addShader(shader.get());
 552                             shaderMap.insert(make_pair(shaderName, shader));
 553                         }
 554                     }
 555                 }
 556             }
 557             pvec = pFragShaders;
 558             stype = Shader::FRAGMENT;
 559         }
 560         programMap.insert(make_pair(programKey, program));
 561     }
 562     pass->setAttributeAndModes(program);
 563 }
 564
 565 InstallAttributeBuilder<ShaderProgramBuilder> installShaderProgram("program");
 566
 567 EffectNameValue<Uniform::Type> uniformTypes[] =
 568 {
 569     {"float", Uniform::FLOAT},
 570     {"float-vec3", Uniform::FLOAT_VEC3},
 571     {"float-vec4", Uniform::FLOAT_VEC4},
 572     {"sampler-1d", Uniform::SAMPLER_1D},
 573     {"sampler-2d", Uniform::SAMPLER_2D},
 574     {"sampler-3d", Uniform::SAMPLER_3D}
 575 };
 576
 577 struct UniformBuilder :public PassAttributeBuilder
 578 {
 579     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 580                         const osgDB::ReaderWriter::Options* options)
 581     {
 582         const SGPropertyNode* nameProp = prop->getChild("name");
 583         const SGPropertyNode* typeProp = prop->getChild("type");
 584         const SGPropertyNode* valProp
 585             = getEffectPropertyChild(effect, prop, "value");
 586         string name;
 587         Uniform::Type uniformType = Uniform::FLOAT;
 588         if (nameProp) {
 589             name = nameProp->getStringValue();
 590         } else {
 591             SG_LOG(SG_INPUT, SG_ALERT, "No name for uniform property ");
 592             return;
 593         }
 594         if (!valProp) {
 595             SG_LOG(SG_INPUT, SG_ALERT, "No value for uniform property "
 596                    << name);
 597             return;
 598         }
 599         if (!typeProp) {
 600             props::Type propType = valProp->getType();
 601             switch (propType) {
 602             case props::FLOAT:
 603             case props::DOUBLE:
 604                 break;          // default float type;
 605             case props::VEC3D:
 606                 uniformType = Uniform::FLOAT_VEC3;
 607                 break;
 608             case props::VEC4D:
 609                 uniformType = Uniform::FLOAT_VEC4;
 610                 break;
 611             default:
 612                 SG_LOG(SG_INPUT, SG_ALERT, "Can't deduce type of uniform "
 613                        << name);
 614                 return;
 615             }
 616         } else {
 617             findAttr(uniformTypes, typeProp, uniformType);
 618         }
 619         ref_ptr<Uniform> uniform = new Uniform;
 620         uniform->setName(name);
 621         uniform->setType(uniformType);
 622         switch (uniformType) {
 623         case Uniform::FLOAT:
 624             uniform->set(valProp->getValue<float>());
 625             break;
 626         case Uniform::FLOAT_VEC3:
 627             uniform->set(toOsg(valProp->getValue<SGVec3d>()));
 628             break;
 629         case Uniform::FLOAT_VEC4:
 630             uniform->set(toOsg(valProp->getValue<SGVec4d>()));
 631             break;
 632         case Uniform::SAMPLER_1D:
 633         case Uniform::SAMPLER_2D:
 634         case Uniform::SAMPLER_3D:
 635             uniform->set(valProp->getValue<int>());
 636             break;
 637         default: // avoid compiler warning
 638             break;
 639         }
 640         pass->addUniform(uniform.get());
 641     }
 642 };
 643
 644 InstallAttributeBuilder<UniformBuilder> installUniform("uniform");
 645
 646 // Not sure what to do with "name". At one point I wanted to use it to
 647 // order the passes, but I do support render bin and stuff too...
 648
 649 struct NameBuilder : public PassAttributeBuilder
 650 {
 651     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 652                         const osgDB::ReaderWriter::Options* options)
 653     {
 654         // name can't use <use>
 655         string name = prop->getStringValue();
 656         if (!name.empty())
 657             pass->setName(name);
 658     }
 659 };
 660
 661 InstallAttributeBuilder<NameBuilder> installName("name");
 662
 663 EffectNameValue<PolygonMode::Mode> polygonModeModes[] =
 664 {
 665     {"fill", PolygonMode::FILL},
 666     {"line", PolygonMode::LINE},
 667     {"point", PolygonMode::POINT}
 668 };
 669
 670 struct PolygonModeBuilder : public PassAttributeBuilder
 671 {
 672     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 673                         const osgDB::ReaderWriter::Options* options)
 674     {
 675         const SGPropertyNode* frontProp
 676             = getEffectPropertyChild(effect, prop, "front");
 677         const SGPropertyNode* backProp
 678             = getEffectPropertyChild(effect, prop, "back");
 679         ref_ptr<PolygonMode> pmode = new PolygonMode;
 680         PolygonMode::Mode frontMode = PolygonMode::FILL;
 681         PolygonMode::Mode backMode = PolygonMode::FILL;
 682         if (frontProp) {
 683             findAttr(polygonModeModes, frontProp, frontMode);
 684             pmode->setMode(PolygonMode::FRONT, frontMode);
 685         }
 686         if (backProp) {
 687             findAttr(polygonModeModes, backProp, backMode);
 688             pmode->setMode(PolygonMode::BACK, backMode);
 689         }
 690         pass->setAttribute(pmode.get());
 691     }
 692 };
 693
 694 InstallAttributeBuilder<PolygonModeBuilder> installPolygonMode("polygon-mode");
 695 void buildTechnique(Effect* effect, const SGPropertyNode* prop,
 696                     const osgDB::ReaderWriter::Options* options)
 697 {
 698     Technique* tniq = new Technique;
 699     effect->techniques.push_back(tniq);
 700     const SGPropertyNode* predProp = prop->getChild("predicate");
 701     if (!predProp) {
 702         tniq->setAlwaysValid(true);
 703     } else {
 704         try {
 705             TechniquePredParser parser;
 706             parser.setTechnique(tniq);
 707             expression::BindingLayout& layout = parser.getBindingLayout();
 708             /*int contextLoc = */layout.addBinding("__contextId", expression::INT);
 709             SGExpressionb* validExp
 710                 = dynamic_cast<SGExpressionb*>(parser.read(predProp
 711                                                            ->getChild(0)));
 712             if (validExp)
 713                 tniq->setValidExpression(validExp, layout);
 714             else
 715                 throw expression::ParseError("technique predicate is not a boolean expression");
 716         }
 717         catch (expression::ParseError& except)
 718         {
 719             SG_LOG(SG_INPUT, SG_ALERT,
 720                    "parsing technique predicate " << except.getMessage());
 721             tniq->setAlwaysValid(false);
 722         }
 723     }
 724     PropertyList passProps = prop->getChildren("pass");
 725     for (PropertyList::iterator itr = passProps.begin(), e = passProps.end();
 726          itr != e;
 727          ++itr) {
 728         buildPass(effect, tniq, itr->ptr(), options);
 729     }
 730 }
 731
 732 // Walk the techniques property tree, building techniques and
 733 // passes.
 734 bool Effect::realizeTechniques(const osgDB::ReaderWriter::Options* options)
 735 {
 736     PropertyList tniqList = root->getChildren("technique");
 737     for (PropertyList::iterator itr = tniqList.begin(), e = tniqList.end();
 738          itr != e;
 739          ++itr)
 740         buildTechnique(this, *itr, options);
 741     return true;
 742 }
 743
 744 bool Effect_writeLocalData(const Object& obj, osgDB::Output& fw)
 745 {
 746     const Effect& effect = static_cast<const Effect&>(obj);
 747
 748     fw.indent() << "techniques " << effect.techniques.size() << "\n";
 749     BOOST_FOREACH(const ref_ptr<Technique>& technique, effect.techniques) {
 750         fw.writeObject(*technique);
 751     }
 752     return true;
 753 }
 754
 755 namespace
 756 {
 757 osgDB::RegisterDotOsgWrapperProxy effectProxy
 758 (
 759     new Effect,
 760     "simgear::Effect",
 761     "Object simgear::Effect",
 762     0,
 763     &Effect_writeLocalData
 764     );
 765 }
 766
 767 // Property expressions for technique predicates
 768 class PropertyExpression : public SGExpression<bool>
 769 {
 770 public:
 771     PropertyExpression(SGPropertyNode* pnode) : _pnode(pnode) {}
 772
 773     void eval(bool& value, const expression::Binding*) const
 774     {
 775         value = _pnode->getValue<bool>();
 776     }
 777 protected:
 778     SGPropertyNode_ptr _pnode;
 779 };
 780
 781 class EffectPropertyListener : public SGPropertyChangeListener
 782 {
 783 public:
 784     EffectPropertyListener(Technique* tniq) : _tniq(tniq) {}
 785
 786     void valueChanged(SGPropertyNode* node)
 787     {
 788         _tniq->refreshValidity();
 789     }
 790 protected:
 791     osg::ref_ptr<Technique> _tniq;
 792 };
 793
 794 Expression* propertyExpressionParser(const SGPropertyNode* exp,
 795                                      expression::Parser* parser)
 796 {
 797     SGPropertyNode_ptr pnode = getPropertyRoot()->getNode(exp->getStringValue(),
 798                                                           true);
 799     PropertyExpression* pexp = new PropertyExpression(pnode);
 800     TechniquePredParser* predParser
 801         = dynamic_cast<TechniquePredParser*>(parser);
 802     if (predParser)
 803         pnode->addChangeListener(new EffectPropertyListener(predParser
 804                                                             ->getTechnique()));
 805     return pexp;
 806 }
 807
 808 expression::ExpParserRegistrar propertyRegistrar("property",
 809                                                  propertyExpressionParser);
 810
 811 }