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