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 "EffectGeode.hxx"
  24 #include "Technique.hxx"
  25 #include "Pass.hxx"
  26 #include "TextureBuilder.hxx"
  27
  28 #include <algorithm>
  29 #include <functional>
  30 #include <iterator>
  31 #include <map>
  32 #include <utility>
  33 #include <boost/tr1/unordered_map.hpp>
  34
  35 #include <boost/bind.hpp>
  36 #include <boost/foreach.hpp>
  37 #include <boost/functional/hash.hpp>
  38 #include <boost/tuple/tuple.hpp>
  39 #include <boost/tuple/tuple_comparison.hpp>
  40
  41 #include <osg/AlphaFunc>
  42 #include <osg/BlendFunc>
  43 #include <osg/CullFace>
  44 #include <osg/Depth>
  45 #include <osg/Drawable>
  46 #include <osg/Material>
  47 #include <osg/Math>
  48 #include <osg/PolygonMode>
  49 #include <osg/Program>
  50 #include <osg/Referenced>
  51 #include <osg/RenderInfo>
  52 #include <osg/ShadeModel>
  53 #include <osg/StateSet>
  54 #include <osg/Stencil>
  55 #include <osg/TexEnv>
  56 #include <osg/Texture1D>
  57 #include <osg/Texture2D>
  58 #include <osg/Texture3D>
  59 #include <osg/TextureRectangle>
  60 #include <osg/Uniform>
  61 #include <osg/Vec4d>
  62 #include <osgUtil/CullVisitor>
  63 #include <osgDB/FileUtils>
  64 #include <osgDB/Input>
  65 #include <osgDB/ParameterOutput>
  66 #include <osgDB/ReadFile>
  67 #include <osgDB/Registry>
  68
  69 #include <simgear/scene/model/SGReaderWriterXMLOptions.hxx>
  70 #include <simgear/scene/tgdb/userdata.hxx>
  71 #include <simgear/scene/util/SGSceneFeatures.hxx>
  72 #include <simgear/scene/util/StateAttributeFactory.hxx>
  73 #include <simgear/structure/OSGUtils.hxx>
  74 #include <simgear/structure/SGExpression.hxx>
  75
  76
  77
  78 namespace simgear
  79 {
  80 using namespace std;
  81 using namespace osg;
  82 using namespace osgUtil;
  83
  84 using namespace effect;
  85
  86 Effect::Effect()
  87     : _cache(0), _isRealized(false)
  88 {
  89 }
  90
  91 Effect::Effect(const Effect& rhs, const CopyOp& copyop)
  92     : root(rhs.root), parametersProp(rhs.parametersProp), _cache(0),
  93       _isRealized(rhs._isRealized)
  94 {
  95     typedef vector<ref_ptr<Technique> > TechniqueList;
  96     for (TechniqueList::const_iterator itr = rhs.techniques.begin(),
  97              end = rhs.techniques.end();
  98          itr != end;
  99          ++itr)
 100         techniques.push_back(static_cast<Technique*>(copyop(itr->get())));
 101 }
 102
 103 // Assume that the last technique is always valid.
 104 StateSet* Effect::getDefaultStateSet()
 105 {
 106     Technique* tniq = techniques.back().get();
 107     if (!tniq)
 108         return 0;
 109     Pass* pass = tniq->passes.front().get();
 110     return pass;
 111 }
 112
 113 // There should always be a valid technique in an effect.
 114
 115 Technique* Effect::chooseTechnique(RenderInfo* info)
 116 {
 117     BOOST_FOREACH(ref_ptr<Technique>& technique, techniques)
 118     {
 119         if (technique->valid(info) == Technique::VALID)
 120             return technique.get();
 121     }
 122     return 0;
 123 }
 124
 125 void Effect::resizeGLObjectBuffers(unsigned int maxSize)
 126 {
 127     BOOST_FOREACH(const ref_ptr<Technique>& technique, techniques)
 128     {
 129         technique->resizeGLObjectBuffers(maxSize);
 130     }
 131 }
 132
 133 void Effect::releaseGLObjects(osg::State* state) const
 134 {
 135     BOOST_FOREACH(const ref_ptr<Technique>& technique, techniques)
 136     {
 137         technique->releaseGLObjects(state);
 138     }
 139 }
 140
 141 Effect::~Effect()
 142 {
 143     delete _cache;
 144 }
 145
 146 void buildPass(Effect* effect, Technique* tniq, const SGPropertyNode* prop,
 147                const SGReaderWriterXMLOptions* options)
 148 {
 149     Pass* pass = new Pass;
 150     tniq->passes.push_back(pass);
 151     for (int i = 0; i < prop->nChildren(); ++i) {
 152         const SGPropertyNode* attrProp = prop->getChild(i);
 153         PassAttributeBuilder* builder
 154             = PassAttributeBuilder::find(attrProp->getNameString());
 155         if (builder)
 156             builder->buildAttribute(effect, pass, attrProp, options);
 157         else
 158             SG_LOG(SG_INPUT, SG_ALERT,
 159                    "skipping unknown pass attribute " << attrProp->getName());
 160     }
 161 }
 162
 163 // Default names for vector property components
 164 const char* vec3Names[] = {"x", "y", "z"};
 165 const char* vec4Names[] = {"x", "y", "z", "w"};
 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 SGReaderWriterXMLOptions* options);
 197 };
 198
 199 void LightingBuilder::buildAttribute(Effect* effect, Pass* pass,
 200                                      const SGPropertyNode* prop,
 201                                      const SGReaderWriterXMLOptions* 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 SGReaderWriterXMLOptions* 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 SGReaderWriterXMLOptions* options)
 238     {
 239         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 240         if (!realProp) {
 241             pass->setMode(GL_CULL_FACE, StateAttribute::OFF);
 242             return;
 243         }
 244         StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 245         string propVal = realProp->getStringValue();
 246         if (propVal == "front")
 247             pass->setAttributeAndModes(attrFact->getCullFaceFront());
 248         else if (propVal == "back")
 249             pass->setAttributeAndModes(attrFact->getCullFaceBack());
 250         else if (propVal == "front-back")
 251             pass->setAttributeAndModes(new CullFace(CullFace::FRONT_AND_BACK));
 252         else if (propVal == "off")
 253             pass->setMode(GL_CULL_FACE, StateAttribute::OFF);
 254         else
 255             SG_LOG(SG_INPUT, SG_ALERT,
 256                    "invalid cull face property " << propVal);
 257     }
 258 };
 259
 260 InstallAttributeBuilder<CullFaceBuilder> installCullFace("cull-face");
 261
 262 struct ColorMaskBuilder : PassAttributeBuilder
 263 {
 264     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 265                         const SGReaderWriterXMLOptions* options)
 266     {
 267         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 268         if (!realProp)
 269             return;
 270
 271         ColorMask *mask = new ColorMask;
 272         Vec4 m = getColor(realProp);
 273         mask->setMask(m.r(), m.g(), m.b(), m.a());
 274         pass->setAttributeAndModes(mask);
 275     }
 276 };
 277
 278 InstallAttributeBuilder<ColorMaskBuilder> installColorMask("color-mask");
 279
 280 EffectNameValue<StateSet::RenderingHint> renderingHintInit[] =
 281 {
 282     { "default", StateSet::DEFAULT_BIN },
 283     { "opaque", StateSet::OPAQUE_BIN },
 284     { "transparent", StateSet::TRANSPARENT_BIN }
 285 };
 286
 287 EffectPropertyMap<StateSet::RenderingHint> renderingHints(renderingHintInit);
 288
 289 struct HintBuilder : public PassAttributeBuilder
 290 {
 291     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 292                         const SGReaderWriterXMLOptions* options)
 293     {
 294         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 295         if (!realProp)
 296             return;
 297         StateSet::RenderingHint renderingHint = StateSet::DEFAULT_BIN;
 298         findAttr(renderingHints, realProp, renderingHint);
 299         pass->setRenderingHint(renderingHint);
 300     }
 301 };
 302
 303 InstallAttributeBuilder<HintBuilder> installHint("rendering-hint");
 304
 305 struct RenderBinBuilder : public PassAttributeBuilder
 306 {
 307     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 308                         const SGReaderWriterXMLOptions* options)
 309     {
 310         if (!isAttributeActive(effect, prop))
 311             return;
 312         const SGPropertyNode* binProp = prop->getChild("bin-number");
 313         binProp = getEffectPropertyNode(effect, binProp);
 314         const SGPropertyNode* nameProp = prop->getChild("bin-name");
 315         nameProp = getEffectPropertyNode(effect, nameProp);
 316         if (binProp && nameProp) {
 317             pass->setRenderBinDetails(binProp->getIntValue(),
 318                                       nameProp->getStringValue());
 319         } else {
 320             if (!binProp)
 321                 SG_LOG(SG_INPUT, SG_ALERT,
 322                        "No render bin number specified in render bin section");
 323             if (!nameProp)
 324                 SG_LOG(SG_INPUT, SG_ALERT,
 325                        "No render bin name specified in render bin section");
 326         }
 327     }
 328 };
 329
 330 InstallAttributeBuilder<RenderBinBuilder> installRenderBin("render-bin");
 331
 332 struct MaterialBuilder : public PassAttributeBuilder
 333 {
 334     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 335                         const SGReaderWriterXMLOptions* options);
 336 };
 337
 338 EffectNameValue<Material::ColorMode> colorModeInit[] =
 339 {
 340     { "ambient", Material::AMBIENT },
 341     { "ambient-and-diffuse", Material::AMBIENT_AND_DIFFUSE },
 342     { "diffuse", Material::DIFFUSE },
 343     { "emissive", Material::EMISSION },
 344     { "specular", Material::SPECULAR },
 345     { "off", Material::OFF }
 346 };
 347 EffectPropertyMap<Material::ColorMode> colorModes(colorModeInit);
 348
 349 void MaterialBuilder::buildAttribute(Effect* effect, Pass* pass,
 350                                      const SGPropertyNode* prop,
 351                                      const SGReaderWriterXMLOptions* options)
 352 {
 353     if (!isAttributeActive(effect, prop))
 354         return;
 355     Material* mat = new Material;
 356     const SGPropertyNode* color = 0;
 357     if ((color = getEffectPropertyChild(effect, prop, "ambient")))
 358         mat->setAmbient(Material::FRONT_AND_BACK, getColor(color));
 359     if ((color = getEffectPropertyChild(effect, prop, "ambient-front")))
 360         mat->setAmbient(Material::FRONT, getColor(color));
 361     if ((color = getEffectPropertyChild(effect, prop, "ambient-back")))
 362         mat->setAmbient(Material::BACK, getColor(color));
 363     if ((color = getEffectPropertyChild(effect, prop, "diffuse")))
 364         mat->setDiffuse(Material::FRONT_AND_BACK, getColor(color));
 365     if ((color = getEffectPropertyChild(effect, prop, "diffuse-front")))
 366         mat->setDiffuse(Material::FRONT, getColor(color));
 367     if ((color = getEffectPropertyChild(effect, prop, "diffuse-back")))
 368         mat->setDiffuse(Material::BACK, getColor(color));
 369     if ((color = getEffectPropertyChild(effect, prop, "specular")))
 370         mat->setSpecular(Material::FRONT_AND_BACK, getColor(color));
 371     if ((color = getEffectPropertyChild(effect, prop, "specular-front")))
 372         mat->setSpecular(Material::FRONT, getColor(color));
 373     if ((color = getEffectPropertyChild(effect, prop, "specular-back")))
 374         mat->setSpecular(Material::BACK, getColor(color));
 375     if ((color = getEffectPropertyChild(effect, prop, "emissive")))
 376         mat->setEmission(Material::FRONT_AND_BACK, getColor(color));
 377     if ((color = getEffectPropertyChild(effect, prop, "emissive-front")))
 378         mat->setEmission(Material::FRONT, getColor(color));
 379     if ((color = getEffectPropertyChild(effect, prop, "emissive-back")))
 380         mat->setEmission(Material::BACK, getColor(color));
 381     const SGPropertyNode* shininess = 0;
 382     mat->setShininess(Material::FRONT_AND_BACK, 0.0f);
 383     if ((shininess = getEffectPropertyChild(effect, prop, "shininess")))
 384         mat->setShininess(Material::FRONT_AND_BACK, shininess->getFloatValue());
 385     if ((shininess = getEffectPropertyChild(effect, prop, "shininess-front")))
 386         mat->setShininess(Material::FRONT, shininess->getFloatValue());
 387     if ((shininess = getEffectPropertyChild(effect, prop, "shininess-back")))
 388         mat->setShininess(Material::BACK, shininess->getFloatValue());
 389     Material::ColorMode colorMode = Material::OFF;
 390     findAttr(colorModes, getEffectPropertyChild(effect, prop, "color-mode"),
 391              colorMode);
 392     mat->setColorMode(colorMode);
 393     pass->setAttribute(mat);
 394 }
 395
 396 InstallAttributeBuilder<MaterialBuilder> installMaterial("material");
 397
 398 EffectNameValue<BlendFunc::BlendFuncMode> blendFuncModesInit[] =
 399 {
 400     {"dst-alpha", BlendFunc::DST_ALPHA},
 401     {"dst-color", BlendFunc::DST_COLOR},
 402     {"one", BlendFunc::ONE},
 403     {"one-minus-dst-alpha", BlendFunc::ONE_MINUS_DST_ALPHA},
 404     {"one-minus-dst-color", BlendFunc::ONE_MINUS_DST_COLOR},
 405     {"one-minus-src-alpha", BlendFunc::ONE_MINUS_SRC_ALPHA},
 406     {"one-minus-src-color", BlendFunc::ONE_MINUS_SRC_COLOR},
 407     {"src-alpha", BlendFunc::SRC_ALPHA},
 408     {"src-alpha-saturate", BlendFunc::SRC_ALPHA_SATURATE},
 409     {"src-color", BlendFunc::SRC_COLOR},
 410     {"constant-color", BlendFunc::CONSTANT_COLOR},
 411     {"one-minus-constant-color", BlendFunc::ONE_MINUS_CONSTANT_COLOR},
 412     {"constant-alpha", BlendFunc::CONSTANT_ALPHA},
 413     {"one-minus-constant-alpha", BlendFunc::ONE_MINUS_CONSTANT_ALPHA},
 414     {"zero", BlendFunc::ZERO}
 415 };
 416 EffectPropertyMap<BlendFunc::BlendFuncMode> blendFuncModes(blendFuncModesInit);
 417
 418 struct BlendBuilder : public PassAttributeBuilder
 419 {
 420     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 421                         const SGReaderWriterXMLOptions* options)
 422     {
 423         if (!isAttributeActive(effect, prop))
 424             return;
 425         // XXX Compatibility with early <blend> syntax; should go away
 426         // before a release
 427         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 428         if (!realProp)
 429             return;
 430         if (realProp->nChildren() == 0) {
 431             pass->setMode(GL_BLEND, (realProp->getBoolValue()
 432                                      ? StateAttribute::ON
 433                                      : StateAttribute::OFF));
 434             return;
 435         }
 436
 437         const SGPropertyNode* pmode = getEffectPropertyChild(effect, prop,
 438                                                              "mode");
 439         // XXX When dynamic parameters are supported, this code should
 440         // create the blend function even if the mode is off.
 441         if (pmode && !pmode->getValue<bool>()) {
 442             pass->setMode(GL_BLEND, StateAttribute::OFF);
 443             return;
 444         }
 445         const SGPropertyNode* psource
 446             = getEffectPropertyChild(effect, prop, "source");
 447         const SGPropertyNode* pdestination
 448             = getEffectPropertyChild(effect, prop, "destination");
 449         const SGPropertyNode* psourceRGB
 450             = getEffectPropertyChild(effect, prop, "source-rgb");
 451         const SGPropertyNode* psourceAlpha
 452             = getEffectPropertyChild(effect, prop, "source-alpha");
 453         const SGPropertyNode* pdestRGB
 454             = getEffectPropertyChild(effect, prop, "destination-rgb");
 455         const SGPropertyNode* pdestAlpha
 456             = getEffectPropertyChild(effect, prop, "destination-alpha");
 457         BlendFunc::BlendFuncMode sourceMode = BlendFunc::ONE;
 458         BlendFunc::BlendFuncMode destMode = BlendFunc::ZERO;
 459         if (psource)
 460             findAttr(blendFuncModes, psource, sourceMode);
 461         if (pdestination)
 462             findAttr(blendFuncModes, pdestination, destMode);
 463         if (psource && pdestination
 464             && !(psourceRGB || psourceAlpha || pdestRGB || pdestAlpha)
 465             && sourceMode == BlendFunc::SRC_ALPHA
 466             && destMode == BlendFunc::ONE_MINUS_SRC_ALPHA) {
 467             pass->setAttributeAndModes(StateAttributeFactory::instance()
 468                                        ->getStandardBlendFunc());
 469             return;
 470         }
 471         BlendFunc* blendFunc = new BlendFunc;
 472         if (psource)
 473             blendFunc->setSource(sourceMode);
 474         if (pdestination)
 475             blendFunc->setDestination(destMode);
 476         if (psourceRGB) {
 477             BlendFunc::BlendFuncMode sourceRGBMode;
 478             findAttr(blendFuncModes, psourceRGB, sourceRGBMode);
 479             blendFunc->setSourceRGB(sourceRGBMode);
 480         }
 481         if (pdestRGB) {
 482             BlendFunc::BlendFuncMode destRGBMode;
 483             findAttr(blendFuncModes, pdestRGB, destRGBMode);
 484             blendFunc->setDestinationRGB(destRGBMode);
 485         }
 486         if (psourceAlpha) {
 487             BlendFunc::BlendFuncMode sourceAlphaMode;
 488             findAttr(blendFuncModes, psourceAlpha, sourceAlphaMode);
 489             blendFunc->setSourceAlpha(sourceAlphaMode);
 490         }
 491         if (pdestAlpha) {
 492             BlendFunc::BlendFuncMode destAlphaMode;
 493             findAttr(blendFuncModes, pdestAlpha, destAlphaMode);
 494             blendFunc->setDestinationAlpha(destAlphaMode);
 495         }
 496         pass->setAttributeAndModes(blendFunc);
 497     }
 498 };
 499
 500 InstallAttributeBuilder<BlendBuilder> installBlend("blend");
 501
 502
 503 EffectNameValue<Stencil::Function> stencilFunctionInit[] =
 504 {
 505     {"never", Stencil::NEVER },
 506     {"less", Stencil::LESS},
 507     {"equal", Stencil::EQUAL},
 508     {"less-or-equal", Stencil::LEQUAL},
 509     {"greater", Stencil::GREATER},
 510     {"not-equal", Stencil::NOTEQUAL},
 511     {"greater-or-equal", Stencil::GEQUAL},
 512     {"always", Stencil::ALWAYS}
 513 };
 514
 515 EffectPropertyMap<Stencil::Function> stencilFunction(stencilFunctionInit);
 516
 517 EffectNameValue<Stencil::Operation> stencilOperationInit[] =
 518 {
 519     {"keep", Stencil::KEEP},
 520     {"zero", Stencil::ZERO},
 521     {"replace", Stencil::REPLACE},
 522     {"increase", Stencil::INCR},
 523     {"decrease", Stencil::DECR},
 524     {"invert", Stencil::INVERT},
 525     {"increase-wrap", Stencil::INCR_WRAP},
 526     {"decrease-wrap", Stencil::DECR_WRAP}
 527 };
 528
 529 EffectPropertyMap<Stencil::Operation> stencilOperation(stencilOperationInit);
 530
 531 struct StencilBuilder : public PassAttributeBuilder
 532 {
 533     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 534                         const SGReaderWriterXMLOptions* options)
 535     {
 536         if (!isAttributeActive(effect, prop))
 537             return;
 538
 539         const SGPropertyNode* pmode = getEffectPropertyChild(effect, prop,
 540                                                              "mode");
 541         if (pmode && !pmode->getValue<bool>()) {
 542             pass->setMode(GL_STENCIL, StateAttribute::OFF);
 543             return;
 544         }
 545         const SGPropertyNode* pfunction
 546             = getEffectPropertyChild(effect, prop, "function");
 547         const SGPropertyNode* pvalue
 548             = getEffectPropertyChild(effect, prop, "value");
 549         const SGPropertyNode* pmask
 550             = getEffectPropertyChild(effect, prop, "mask");
 551         const SGPropertyNode* psfail
 552             = getEffectPropertyChild(effect, prop, "stencil-fail");
 553         const SGPropertyNode* pzfail
 554             = getEffectPropertyChild(effect, prop, "z-fail");
 555         const SGPropertyNode* ppass
 556             = getEffectPropertyChild(effect, prop, "pass");
 557
 558         Stencil::Function func = Stencil::ALWAYS;  // Always pass
 559         int ref = 0;
 560         unsigned int mask = ~0u;  // All bits on
 561         Stencil::Operation sfailop = Stencil::KEEP;  // Keep the old values as default
 562         Stencil::Operation zfailop = Stencil::KEEP;
 563         Stencil::Operation passop = Stencil::KEEP;
 564
 565         ref_ptr<Stencil> stencilFunc = new Stencil;
 566
 567         if (pfunction)
 568             findAttr(stencilFunction, pfunction, func);
 569         if (pvalue)
 570             ref = pvalue->getIntValue();
 571         if (pmask)
 572             mask = pmask->getIntValue();
 573
 574         if (psfail)
 575             findAttr(stencilOperation, psfail, sfailop);
 576         if (pzfail)
 577             findAttr(stencilOperation, pzfail, zfailop);
 578         if (ppass)
 579             findAttr(stencilOperation, ppass, passop);
 580
 581         // Set the stencil operation
 582         stencilFunc->setFunction(func, ref, mask);
 583
 584         // Set the operation, s-fail, s-pass/z-fail, s-pass/z-pass
 585         stencilFunc->setOperation(sfailop, zfailop, passop);
 586
 587         // Add the operation to pass
 588         pass->setAttributeAndModes(stencilFunc.get());
 589     }
 590 };
 591
 592 InstallAttributeBuilder<StencilBuilder> installStencil("stencil");
 593
 594
 595 EffectNameValue<AlphaFunc::ComparisonFunction> alphaComparisonInit[] =
 596 {
 597     {"never", AlphaFunc::NEVER},
 598     {"less", AlphaFunc::LESS},
 599     {"equal", AlphaFunc::EQUAL},
 600     {"lequal", AlphaFunc::LEQUAL},
 601     {"greater", AlphaFunc::GREATER},
 602     {"notequal", AlphaFunc::NOTEQUAL},
 603     {"gequal", AlphaFunc::GEQUAL},
 604     {"always", AlphaFunc::ALWAYS}
 605 };
 606 EffectPropertyMap<AlphaFunc::ComparisonFunction>
 607 alphaComparison(alphaComparisonInit);
 608
 609 struct AlphaTestBuilder : public PassAttributeBuilder
 610 {
 611     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 612                         const SGReaderWriterXMLOptions* options)
 613     {
 614         if (!isAttributeActive(effect, prop))
 615             return;
 616         // XXX Compatibility with early <alpha-test> syntax; should go away
 617         // before a release
 618         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 619         if (!realProp)
 620             return;
 621         if (realProp->nChildren() == 0) {
 622             pass->setMode(GL_ALPHA_TEST, (realProp->getBoolValue()
 623                                      ? StateAttribute::ON
 624                                      : StateAttribute::OFF));
 625             return;
 626         }
 627
 628         const SGPropertyNode* pmode = getEffectPropertyChild(effect, prop,
 629                                                              "mode");
 630         // XXX When dynamic parameters are supported, this code should
 631         // create the blend function even if the mode is off.
 632         if (pmode && !pmode->getValue<bool>()) {
 633             pass->setMode(GL_ALPHA_TEST, StateAttribute::OFF);
 634             return;
 635         }
 636         const SGPropertyNode* pComp = getEffectPropertyChild(effect, prop,
 637                                                              "comparison");
 638         const SGPropertyNode* pRef = getEffectPropertyChild(effect, prop,
 639                                                              "reference");
 640         AlphaFunc::ComparisonFunction func = AlphaFunc::ALWAYS;
 641         float refValue = 1.0f;
 642         if (pComp)
 643             findAttr(alphaComparison, pComp, func);
 644         if (pRef)
 645             refValue = pRef->getValue<float>();
 646         if (func == AlphaFunc::GREATER && osg::equivalent(refValue, 1.0f)) {
 647             pass->setAttributeAndModes(StateAttributeFactory::instance()
 648                                        ->getStandardAlphaFunc());
 649         } else {
 650             AlphaFunc* alphaFunc = new AlphaFunc;
 651             alphaFunc->setFunction(func);
 652             alphaFunc->setReferenceValue(refValue);
 653             pass->setAttributeAndModes(alphaFunc);
 654         }
 655     }
 656 };
 657
 658 InstallAttributeBuilder<AlphaTestBuilder> installAlphaTest("alpha-test");
 659
 660 InstallAttributeBuilder<TextureUnitBuilder> textureUnitBuilder("texture-unit");
 661
 662 // Shader key, used both for shaders with relative and absolute names
 663 typedef pair<string, Shader::Type> ShaderKey;
 664
 665 struct ProgramKey
 666 {
 667     typedef pair<string, int> AttribKey;
 668     osgDB::FilePathList paths;
 669     vector<ShaderKey> shaders;
 670     vector<AttribKey> attributes;
 671     struct EqualTo
 672     {
 673         bool operator()(const ProgramKey& lhs, const ProgramKey& rhs) const
 674         {
 675             return (lhs.paths.size() == rhs.paths.size()
 676                     && equal(lhs.paths.begin(), lhs.paths.end(),
 677                              rhs.paths.begin())
 678                     && lhs.shaders.size() == rhs.shaders.size()
 679                     && equal (lhs.shaders.begin(), lhs.shaders.end(),
 680                               rhs.shaders.begin())
 681                     && lhs.attributes.size() == rhs.attributes.size()
 682                     && equal(lhs.attributes.begin(), lhs.attributes.end(),
 683                              rhs.attributes.begin()));
 684         }
 685     };
 686 };
 687
 688 size_t hash_value(const ProgramKey& key)
 689 {
 690     size_t seed = 0;
 691     boost::hash_range(seed, key.paths.begin(), key.paths.end());
 692     boost::hash_range(seed, key.shaders.begin(), key.shaders.end());
 693     boost::hash_range(seed, key.attributes.begin(), key.attributes.end());
 694     return seed;
 695 }
 696
 697 // XXX Should these be protected by a mutex? Probably
 698
 699 typedef tr1::unordered_map<ProgramKey, ref_ptr<Program>,
 700                            boost::hash<ProgramKey>, ProgramKey::EqualTo>
 701 ProgramMap;
 702 ProgramMap programMap;
 703
 704 typedef tr1::unordered_map<ShaderKey, ref_ptr<Shader>, boost::hash<ShaderKey> >
 705 ShaderMap;
 706 ShaderMap shaderMap;
 707
 708 void reload_shaders()
 709 {
 710     for(ShaderMap::iterator sitr = shaderMap.begin(); sitr != shaderMap.end(); ++sitr)
 711     {
 712         Shader *shader = sitr->second.get();
 713         string fileName = osgDB::findDataFile(sitr->first.first);
 714         if (!fileName.empty()) {
 715             shader->loadShaderSourceFromFile(fileName);
 716         }
 717     }
 718 }
 719
 720 struct ShaderProgramBuilder : PassAttributeBuilder
 721 {
 722     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 723                         const SGReaderWriterXMLOptions* options);
 724 };
 725
 726 void ShaderProgramBuilder::buildAttribute(Effect* effect, Pass* pass,
 727                                           const SGPropertyNode* prop,
 728                                           const SGReaderWriterXMLOptions*
 729                                           options)
 730 {
 731     using namespace boost;
 732     if (!isAttributeActive(effect, prop))
 733         return;
 734     PropertyList pVertShaders = prop->getChildren("vertex-shader");
 735     PropertyList pFragShaders = prop->getChildren("fragment-shader");
 736     PropertyList pAttributes = prop->getChildren("attribute");
 737     ProgramKey prgKey;
 738     for (PropertyList::iterator itr = pVertShaders.begin(),
 739              e = pVertShaders.end();
 740          itr != e;
 741          ++itr)
 742         prgKey.shaders.push_back(ShaderKey((*itr)->getStringValue(),
 743                                            Shader::VERTEX));
 744     for (PropertyList::iterator itr = pFragShaders.begin(),
 745              e = pFragShaders.end();
 746          itr != e;
 747          ++itr)
 748         prgKey.shaders.push_back(ShaderKey((*itr)->getStringValue(),
 749                                            Shader::FRAGMENT));
 750     for (PropertyList::iterator itr = pAttributes.begin(),
 751              e = pAttributes.end();
 752          itr != e;
 753          ++itr) {
 754         const SGPropertyNode* pName = getEffectPropertyChild(effect, *itr,
 755                                                              "name");
 756         const SGPropertyNode* pIndex = getEffectPropertyChild(effect, *itr,
 757                                                               "index");
 758         if (!pName || ! pIndex)
 759             throw BuilderException("malformed attribute property");
 760         prgKey.attributes
 761             .push_back(ProgramKey::AttribKey(pName->getStringValue(),
 762                                              pIndex->getValue<int>()));
 763     }
 764     if (options)
 765         prgKey.paths = options->getDatabasePathList();
 766     Program* program = 0;
 767     ProgramMap::iterator pitr = programMap.find(prgKey);
 768     if (pitr != programMap.end()) {
 769         program = pitr->second.get();
 770     } else {
 771         program = new Program;
 772         // Add vertex shaders, then fragment shaders
 773         PropertyList& pvec = pVertShaders;
 774         Shader::Type stype = Shader::VERTEX;
 775         for (int i = 0; i < 2; ++i) {
 776             for (PropertyList::iterator nameItr = pvec.begin(), e = pvec.end();
 777                  nameItr != e;
 778                  ++nameItr) {
 779                 string shaderName = (*nameItr)->getStringValue();
 780                 string fileName = osgDB::findDataFile(shaderName, options);
 781                 if (fileName.empty())
 782                     throw BuilderException(string("couldn't find shader ") +
 783                                            shaderName);
 784                 ShaderKey skey(fileName, stype);
 785                 ShaderMap::iterator sitr = shaderMap.find(skey);
 786                 if (sitr != shaderMap.end()) {
 787                     program->addShader(sitr->second.get());
 788                 } else {
 789                     ref_ptr<Shader> shader = new Shader(stype);
 790                     if (shader->loadShaderSourceFromFile(fileName)) {
 791                         program->addShader(shader.get());
 792                         shaderMap.insert(ShaderMap::value_type(skey, shader));
 793                     }
 794                 }
 795             }
 796             pvec = pFragShaders;
 797             stype = Shader::FRAGMENT;
 798         }
 799         BOOST_FOREACH(const ProgramKey::AttribKey& key, prgKey.attributes) {
 800             program->addBindAttribLocation(key.first, key.second);
 801         }
 802        programMap.insert(ProgramMap::value_type(prgKey, program));
 803     }
 804     pass->setAttributeAndModes(program);
 805 }
 806
 807 InstallAttributeBuilder<ShaderProgramBuilder> installShaderProgram("program");
 808
 809 EffectNameValue<Uniform::Type> uniformTypesInit[] =
 810 {
 811     {"float", Uniform::FLOAT},
 812     {"float-vec3", Uniform::FLOAT_VEC3},
 813     {"float-vec4", Uniform::FLOAT_VEC4},
 814     {"sampler-1d", Uniform::SAMPLER_1D},
 815     {"sampler-1d-shadow", Uniform::SAMPLER_1D_SHADOW},
 816     {"sampler-2d", Uniform::SAMPLER_2D},
 817     {"sampler-2d-shadow", Uniform::SAMPLER_2D_SHADOW},
 818     {"sampler-3d", Uniform::SAMPLER_3D},
 819     {"sampler-cube", Uniform::SAMPLER_CUBE}
 820 };
 821 EffectPropertyMap<Uniform::Type> uniformTypes(uniformTypesInit);
 822
 823 struct UniformBuilder :public PassAttributeBuilder
 824 {
 825     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 826                         const SGReaderWriterXMLOptions* options)
 827     {
 828         if (!isAttributeActive(effect, prop))
 829             return;
 830         const SGPropertyNode* nameProp = prop->getChild("name");
 831         const SGPropertyNode* typeProp = prop->getChild("type");
 832         const SGPropertyNode* valProp = prop->getChild("value");
 833         string name;
 834         Uniform::Type uniformType = Uniform::FLOAT;
 835         if (nameProp) {
 836             name = nameProp->getStringValue();
 837         } else {
 838             SG_LOG(SG_INPUT, SG_ALERT, "No name for uniform property ");
 839             return;
 840         }
 841         if (!valProp) {
 842             SG_LOG(SG_INPUT, SG_ALERT, "No value for uniform property "
 843                    << name);
 844             return;
 845         }
 846         if (!typeProp) {
 847             props::Type propType = valProp->getType();
 848             switch (propType) {
 849             case props::FLOAT:
 850             case props::DOUBLE:
 851                 break;          // default float type;
 852             case props::VEC3D:
 853                 uniformType = Uniform::FLOAT_VEC3;
 854                 break;
 855             case props::VEC4D:
 856                 uniformType = Uniform::FLOAT_VEC4;
 857                 break;
 858             default:
 859                 SG_LOG(SG_INPUT, SG_ALERT, "Can't deduce type of uniform "
 860                        << name);
 861                 return;
 862             }
 863         } else {
 864             findAttr(uniformTypes, typeProp, uniformType);
 865         }
 866         ref_ptr<Uniform> uniform = new Uniform;
 867         uniform->setName(name);
 868         uniform->setType(uniformType);
 869         switch (uniformType) {
 870         case Uniform::FLOAT:
 871             initFromParameters(effect, valProp, uniform.get(),
 872                                static_cast<bool (Uniform::*)(float)>(&Uniform::set),
 873                                options);
 874             break;
 875         case Uniform::FLOAT_VEC3:
 876             initFromParameters(effect, valProp, uniform.get(),
 877                                static_cast<bool (Uniform::*)(const Vec3&)>(&Uniform::set),
 878                                vec3Names, options);
 879             break;
 880         case Uniform::FLOAT_VEC4:
 881             initFromParameters(effect, valProp, uniform.get(),
 882                                static_cast<bool (Uniform::*)(const Vec4&)>(&Uniform::set),
 883                                vec4Names, options);
 884             break;
 885         case Uniform::SAMPLER_1D:
 886         case Uniform::SAMPLER_2D:
 887         case Uniform::SAMPLER_3D:
 888         case Uniform::SAMPLER_1D_SHADOW:
 889         case Uniform::SAMPLER_2D_SHADOW:
 890         case Uniform::SAMPLER_CUBE:
 891             initFromParameters(effect, valProp, uniform.get(),
 892                                static_cast<bool (Uniform::*)(int)>(&Uniform::set),
 893                                options);
 894             break;
 895         default: // avoid compiler warning
 896             break;
 897         }
 898         pass->addUniform(uniform.get());
 899     }
 900 };
 901
 902 InstallAttributeBuilder<UniformBuilder> installUniform("uniform");
 903
 904 // Not sure what to do with "name". At one point I wanted to use it to
 905 // order the passes, but I do support render bin and stuff too...
 906
 907 struct NameBuilder : public PassAttributeBuilder
 908 {
 909     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 910                         const SGReaderWriterXMLOptions* options)
 911     {
 912         // name can't use <use>
 913         string name = prop->getStringValue();
 914         if (!name.empty())
 915             pass->setName(name);
 916     }
 917 };
 918
 919 InstallAttributeBuilder<NameBuilder> installName("name");
 920
 921 EffectNameValue<PolygonMode::Mode> polygonModeModesInit[] =
 922 {
 923     {"fill", PolygonMode::FILL},
 924     {"line", PolygonMode::LINE},
 925     {"point", PolygonMode::POINT}
 926 };
 927 EffectPropertyMap<PolygonMode::Mode> polygonModeModes(polygonModeModesInit);
 928
 929 struct PolygonModeBuilder : public PassAttributeBuilder
 930 {
 931     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 932                         const SGReaderWriterXMLOptions* options)
 933     {
 934         if (!isAttributeActive(effect, prop))
 935             return;
 936         const SGPropertyNode* frontProp
 937             = getEffectPropertyChild(effect, prop, "front");
 938         const SGPropertyNode* backProp
 939             = getEffectPropertyChild(effect, prop, "back");
 940         ref_ptr<PolygonMode> pmode = new PolygonMode;
 941         PolygonMode::Mode frontMode = PolygonMode::FILL;
 942         PolygonMode::Mode backMode = PolygonMode::FILL;
 943         if (frontProp) {
 944             findAttr(polygonModeModes, frontProp, frontMode);
 945             pmode->setMode(PolygonMode::FRONT, frontMode);
 946         }
 947         if (backProp) {
 948             findAttr(polygonModeModes, backProp, backMode);
 949             pmode->setMode(PolygonMode::BACK, backMode);
 950         }
 951         pass->setAttribute(pmode.get());
 952     }
 953 };
 954
 955 InstallAttributeBuilder<PolygonModeBuilder> installPolygonMode("polygon-mode");
 956
 957 struct VertexProgramTwoSideBuilder : public PassAttributeBuilder
 958 {
 959     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 960                         const SGReaderWriterXMLOptions* options)
 961     {
 962         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 963         if (!realProp)
 964             return;
 965         pass->setMode(GL_VERTEX_PROGRAM_TWO_SIDE,
 966                       (realProp->getValue<bool>()
 967                        ? StateAttribute::ON : StateAttribute::OFF));
 968     }
 969 };
 970
 971 InstallAttributeBuilder<VertexProgramTwoSideBuilder>
 972 installTwoSide("vertex-program-two-side");
 973
 974 struct VertexProgramPointSizeBuilder : public PassAttributeBuilder
 975 {
 976     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
 977                         const SGReaderWriterXMLOptions* options)
 978     {
 979         const SGPropertyNode* realProp = getEffectPropertyNode(effect, prop);
 980         if (!realProp)
 981             return;
 982         pass->setMode(GL_VERTEX_PROGRAM_POINT_SIZE,
 983                       (realProp->getValue<bool>()
 984                        ? StateAttribute::ON : StateAttribute::OFF));
 985     }
 986 };
 987
 988 InstallAttributeBuilder<VertexProgramPointSizeBuilder>
 989 installPointSize("vertex-program-point-size");
 990
 991 EffectNameValue<Depth::Function> depthFunctionInit[] =
 992 {
 993     {"never", Depth::NEVER},
 994     {"less", Depth::LESS},
 995     {"equal", Depth::EQUAL},
 996     {"lequal", Depth::LEQUAL},
 997     {"greater", Depth::GREATER},
 998     {"notequal", Depth::NOTEQUAL},
 999     {"gequal", Depth::GEQUAL},
1000     {"always", Depth::ALWAYS}
1001 };
1002 EffectPropertyMap<Depth::Function> depthFunction(depthFunctionInit);
1003
1004 struct DepthBuilder : public PassAttributeBuilder
1005 {
1006     void buildAttribute(Effect* effect, Pass* pass, const SGPropertyNode* prop,
1007                         const SGReaderWriterXMLOptions* options)
1008     {
1009         if (!isAttributeActive(effect, prop))
1010             return;
1011         ref_ptr<Depth> depth = new Depth;
1012         const SGPropertyNode* pfunc
1013             = getEffectPropertyChild(effect, prop, "function");
1014         if (pfunc) {
1015             Depth::Function func = Depth::LESS;
1016             findAttr(depthFunction, pfunc, func);
1017             depth->setFunction(func);
1018         }
1019         const SGPropertyNode* pnear
1020             = getEffectPropertyChild(effect, prop, "near");
1021         if (pnear)
1022             depth->setZNear(pnear->getValue<double>());
1023         const SGPropertyNode* pfar
1024             = getEffectPropertyChild(effect, prop, "far");
1025         if (pfar)
1026             depth->setZFar(pnear->getValue<double>());
1027         const SGPropertyNode* pmask
1028             = getEffectPropertyChild(effect, prop, "write-mask");
1029         if (pmask)
1030             depth->setWriteMask(pmask->getValue<bool>());
1031         pass->setAttribute(depth.get());
1032     }
1033 };
1034
1035 InstallAttributeBuilder<DepthBuilder> installDepth("depth");
1036
1037 void buildTechnique(Effect* effect, const SGPropertyNode* prop,
1038                     const SGReaderWriterXMLOptions* options)
1039 {
1040     Technique* tniq = new Technique;
1041     effect->techniques.push_back(tniq);
1042     const SGPropertyNode* predProp = prop->getChild("predicate");
1043     if (!predProp) {
1044         tniq->setAlwaysValid(true);
1045     } else {
1046         try {
1047             TechniquePredParser parser;
1048             parser.setTechnique(tniq);
1049             expression::BindingLayout& layout = parser.getBindingLayout();
1050             /*int contextLoc = */layout.addBinding("__contextId", expression::INT);
1051             SGExpressionb* validExp
1052                 = dynamic_cast<SGExpressionb*>(parser.read(predProp
1053                                                            ->getChild(0)));
1054             if (validExp)
1055                 tniq->setValidExpression(validExp, layout);
1056             else
1057                 throw expression::ParseError("technique predicate is not a boolean expression");
1058         }
1059         catch (expression::ParseError& except)
1060         {
1061             SG_LOG(SG_INPUT, SG_ALERT,
1062                    "parsing technique predicate " << except.getMessage());
1063             tniq->setAlwaysValid(false);
1064         }
1065     }
1066     PropertyList passProps = prop->getChildren("pass");
1067     for (PropertyList::iterator itr = passProps.begin(), e = passProps.end();
1068          itr != e;
1069          ++itr) {
1070         buildPass(effect, tniq, itr->ptr(), options);
1071     }
1072 }
1073
1074 // Specifically for .ac files...
1075 bool makeParametersFromStateSet(SGPropertyNode* effectRoot, const StateSet* ss)
1076 {
1077     SGPropertyNode* paramRoot = makeChild(effectRoot, "parameters");
1078     SGPropertyNode* matNode = paramRoot->getChild("material", 0, true);
1079     Vec4f ambVal, difVal, specVal, emisVal;
1080     float shininess = 0.0f;
1081     const Material* mat = getStateAttribute<Material>(ss);
1082     if (mat) {
1083         ambVal = mat->getAmbient(Material::FRONT_AND_BACK);
1084         difVal = mat->getDiffuse(Material::FRONT_AND_BACK);
1085         specVal = mat->getSpecular(Material::FRONT_AND_BACK);
1086         emisVal = mat->getEmission(Material::FRONT_AND_BACK);
1087         shininess = mat->getShininess(Material::FRONT_AND_BACK);
1088         makeChild(matNode, "active")->setValue(true);
1089         makeChild(matNode, "ambient")->setValue(toVec4d(toSG(ambVal)));
1090         makeChild(matNode, "diffuse")->setValue(toVec4d(toSG(difVal)));
1091         makeChild(matNode, "specular")->setValue(toVec4d(toSG(specVal)));
1092         makeChild(matNode, "emissive")->setValue(toVec4d(toSG(emisVal)));
1093         makeChild(matNode, "shininess")->setValue(shininess);
1094         matNode->getChild("color-mode", 0, true)->setStringValue("diffuse");
1095     } else {
1096         makeChild(matNode, "active")->setValue(false);
1097     }
1098     const ShadeModel* sm = getStateAttribute<ShadeModel>(ss);
1099     string shadeModelString("smooth");
1100     if (sm) {
1101         ShadeModel::Mode smMode = sm->getMode();
1102         if (smMode == ShadeModel::FLAT)
1103             shadeModelString = "flat";
1104     }
1105     makeChild(paramRoot, "shade-model")->setStringValue(shadeModelString);
1106     string cullFaceString("off");
1107     const CullFace* cullFace = getStateAttribute<CullFace>(ss);
1108     if (cullFace) {
1109         switch (cullFace->getMode()) {
1110         case CullFace::FRONT:
1111             cullFaceString = "front";
1112             break;
1113         case CullFace::BACK:
1114             cullFaceString = "back";
1115             break;
1116         case CullFace::FRONT_AND_BACK:
1117             cullFaceString = "front-back";
1118             break;
1119         default:
1120             break;
1121         }
1122     }
1123     makeChild(paramRoot, "cull-face")->setStringValue(cullFaceString);
1124     const BlendFunc* blendFunc = getStateAttribute<BlendFunc>(ss);
1125     SGPropertyNode* blendNode = makeChild(paramRoot, "blend");
1126     if (blendFunc) {
1127         string sourceMode = findName(blendFuncModes, blendFunc->getSource());
1128         string destMode = findName(blendFuncModes, blendFunc->getDestination());
1129         makeChild(blendNode, "active")->setValue(true);
1130         makeChild(blendNode, "source")->setStringValue(sourceMode);
1131         makeChild(blendNode, "destination")->setStringValue(destMode);
1132         makeChild(blendNode, "mode")->setValue(true);
1133     } else {
1134         makeChild(blendNode, "active")->setValue(false);
1135     }
1136     string renderingHint = findName(renderingHints, ss->getRenderingHint());
1137     makeChild(paramRoot, "rendering-hint")->setStringValue(renderingHint);
1138     makeTextureParameters(paramRoot, ss);
1139     return true;
1140 }
1141
1142 // Walk the techniques property tree, building techniques and
1143 // passes.
1144 bool Effect::realizeTechniques(const SGReaderWriterXMLOptions* options)
1145 {
1146     if (_isRealized)
1147         return true;
1148     PropertyList tniqList = root->getChildren("technique");
1149     for (PropertyList::iterator itr = tniqList.begin(), e = tniqList.end();
1150          itr != e;
1151          ++itr)
1152         buildTechnique(this, *itr, options);
1153     _isRealized = true;
1154     return true;
1155 }
1156
1157 void Effect::InitializeCallback::doUpdate(osg::Node* node, osg::NodeVisitor* nv)
1158 {
1159     EffectGeode* eg = dynamic_cast<EffectGeode*>(node);
1160     if (!eg)
1161         return;
1162     Effect* effect = eg->getEffect();
1163     if (!effect)
1164         return;
1165     SGPropertyNode* root = getPropertyRoot();
1166     for (vector<SGSharedPtr<Updater> >::iterator itr = effect->_extraData.begin(),
1167              end = effect->_extraData.end();
1168          itr != end;
1169          ++itr) {
1170         InitializeWhenAdded* adder
1171             = dynamic_cast<InitializeWhenAdded*>(itr->ptr());
1172         if (adder)
1173             adder->initOnAdd(effect, root);
1174     }
1175 }
1176
1177 bool Effect::Key::EqualTo::operator()(const Effect::Key& lhs,
1178                                       const Effect::Key& rhs) const
1179 {
1180     if (lhs.paths.size() != rhs.paths.size()
1181         || !equal(lhs.paths.begin(), lhs.paths.end(), rhs.paths.begin()))
1182         return false;
1183     if (lhs.unmerged.valid() && rhs.unmerged.valid())
1184         return props::Compare()(lhs.unmerged, rhs.unmerged);
1185     else
1186         return lhs.unmerged == rhs.unmerged;
1187 }
1188
1189 size_t hash_value(const Effect::Key& key)
1190 {
1191     size_t seed = 0;
1192     if (key.unmerged.valid())
1193         boost::hash_combine(seed, *key.unmerged);
1194     boost::hash_range(seed, key.paths.begin(), key.paths.end());
1195     return seed;
1196 }
1197
1198 bool Effect_writeLocalData(const Object& obj, osgDB::Output& fw)
1199 {
1200     const Effect& effect = static_cast<const Effect&>(obj);
1201
1202     fw.indent() << "techniques " << effect.techniques.size() << "\n";
1203     BOOST_FOREACH(const ref_ptr<Technique>& technique, effect.techniques) {
1204         fw.writeObject(*technique);
1205     }
1206     return true;
1207 }
1208
1209 namespace
1210 {
1211 osgDB::RegisterDotOsgWrapperProxy effectProxy
1212 (
1213     new Effect,
1214     "simgear::Effect",
1215     "Object simgear::Effect",
1216     0,
1217     &Effect_writeLocalData
1218     );
1219 }
1220
1221 // Property expressions for technique predicates
1222 class PropertyExpression : public SGExpression<bool>
1223 {
1224 public:
1225     PropertyExpression(SGPropertyNode* pnode) : _pnode(pnode) {}
1226
1227     void eval(bool& value, const expression::Binding*) const
1228     {
1229         value = _pnode->getValue<bool>();
1230     }
1231 protected:
1232     SGPropertyNode_ptr _pnode;
1233 };
1234
1235 class EffectPropertyListener : public SGPropertyChangeListener
1236 {
1237 public:
1238     EffectPropertyListener(Technique* tniq) : _tniq(tniq) {}
1239
1240     void valueChanged(SGPropertyNode* node)
1241     {
1242         _tniq->refreshValidity();
1243     }
1244 protected:
1245     osg::ref_ptr<Technique> _tniq;
1246 };
1247
1248 Expression* propertyExpressionParser(const SGPropertyNode* exp,
1249                                      expression::Parser* parser)
1250 {
1251     SGPropertyNode_ptr pnode = getPropertyRoot()->getNode(exp->getStringValue(),
1252                                                           true);
1253     PropertyExpression* pexp = new PropertyExpression(pnode);
1254     TechniquePredParser* predParser
1255         = dynamic_cast<TechniquePredParser*>(parser);
1256     if (predParser)
1257         pnode->addChangeListener(new EffectPropertyListener(predParser
1258                                                             ->getTechnique()));
1259     return pexp;
1260 }
1261
1262 expression::ExpParserRegistrar propertyRegistrar("property",
1263                                                  propertyExpressionParser);
1264
1265 }