simgear/scene/sky/cloud.cxx

   1 // cloud.cxx -- model a single cloud layer
   2 //
   3 // Written by Curtis Olson, started June 2000.
   4 //
   5 // Copyright (C) 2000  Curtis L. Olson  - http://www.flightgear.org/~curt
   6 //
   7 // This library is free software; you can redistribute it and/or
   8 // modify it under the terms of the GNU Library General Public
   9 // License as published by the Free Software Foundation; either
  10 // version 2 of the License, or (at your option) any later version.
  11 //
  12 // This library is distributed in the hope that it will be useful, but
  13 // WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 // General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License
  18 // along with this program; if not, write to the Free Software
  19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20 //
  21
  22 #ifdef HAVE_CONFIG_H
  23 #  include <simgear_config.h>
  24 #endif
  25
  26 #include <simgear/compiler.h>
  27
  28 #include <sstream>
  29
  30 #include <math.h>
  31
  32 #include <simgear/structure/OSGVersion.hxx>
  33 #include <osg/AlphaFunc>
  34 #include <osg/BlendFunc>
  35 #include <osg/CullFace>
  36 #include <osg/Geode>
  37 #include <osg/Geometry>
  38 #include <osg/Material>
  39 #include <osg/ShadeModel>
  40 #include <osg/TexEnv>
  41 #include <osg/TexEnvCombine>
  42 #include <osg/Texture2D>
  43 #include <osg/TextureCubeMap>
  44 #include <osg/TexMat>
  45 #include <osg/Fog>
  46
  47 #include <simgear/math/sg_random.h>
  48 #include <simgear/scene/util/SGReaderWriterOptions.hxx>
  49 #include <simgear/debug/logstream.hxx>
  50 #include <simgear/scene/model/model.hxx>
  51 #include <simgear/scene/util/RenderConstants.hxx>
  52 #include <simgear/scene/util/OsgMath.hxx>
  53 #include <simgear/scene/util/StateAttributeFactory.hxx>
  54 #include <simgear/screen/extensions.hxx>
  55
  56 #include "newcloud.hxx"
  57 #include "cloudfield.hxx"
  58 #include "cloud.hxx"
  59
  60 using namespace simgear;
  61 using namespace osg;
  62
  63 #if defined(__MINGW32__)
  64 #define isnan(x) _isnan(x)
  65 #endif
  66
  67 // #if defined (__FreeBSD__)
  68 // #  if __FreeBSD_version < 500000
  69 //      extern "C" {
  70 //        inline int isnan(double r) { return !(r <= 0 || r >= 0); }
  71 //      }
  72 // #  endif
  73 // #endif
  74
  75 static osg::ref_ptr<osg::StateSet> layer_states[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
  76 static osg::ref_ptr<osg::StateSet> layer_states2[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
  77 static osg::ref_ptr<osg::TextureCubeMap> cubeMap;
  78 static bool state_initialized = false;
  79
  80 const std::string SGCloudLayer::SG_CLOUD_OVERCAST_STRING = "overcast";
  81 const std::string SGCloudLayer::SG_CLOUD_BROKEN_STRING = "broken";
  82 const std::string SGCloudLayer::SG_CLOUD_SCATTERED_STRING = "scattered";
  83 const std::string SGCloudLayer::SG_CLOUD_FEW_STRING = "few";
  84 const std::string SGCloudLayer::SG_CLOUD_CIRRUS_STRING = "cirrus";
  85 const std::string SGCloudLayer::SG_CLOUD_CLEAR_STRING = "clear";
  86
  87 // make an StateSet for a cloud layer given the named texture
  88 static osg::StateSet*
  89 SGMakeState(const SGPath &path, const char* colorTexture,
  90             const char* normalTexture)
  91 {
  92     osg::StateSet *stateSet = new osg::StateSet;
  93
  94     osg::ref_ptr<SGReaderWriterOptions> options;
  95     options = SGReaderWriterOptions::fromPath(path.str());
  96     stateSet->setTextureAttribute(0, SGLoadTexture2D(colorTexture,
  97                                                      options.get()));
  98     stateSet->setTextureMode(0, GL_TEXTURE_2D, osg::StateAttribute::ON);
  99     StateAttributeFactory* attribFactory = StateAttributeFactory::instance();
 100     stateSet->setAttributeAndModes(attribFactory->getSmoothShadeModel());
 101     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 102     stateSet->setAttributeAndModes(attribFactory->getStandardAlphaFunc());
 103     stateSet->setAttributeAndModes(attribFactory->getStandardBlendFunc());
 104
 105 //     osg::Material* material = new osg::Material;
 106 //     material->setColorMode(osg::Material::AMBIENT_AND_DIFFUSE);
 107 //     material->setEmission(osg::Material::FRONT_AND_BACK,
 108 //                           osg::Vec4(0.05, 0.05, 0.05, 0));
 109 //     material->setSpecular(osg::Material::FRONT_AND_BACK,
 110 //                           osg::Vec4(0, 0, 0, 1));
 111 //     stateSet->setAttribute(material);
 112
 113     stateSet->setMode(GL_FOG, osg::StateAttribute::OFF);
 114
 115     // OSGFIXME: invented by me ...
 116 //     stateSet->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
 117 //     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::ON);
 118
 119 //     stateSet->setMode(GL_LIGHT0, osg::StateAttribute::OFF);
 120
 121     // If the normal texture is given prepare a bumpmapping enabled state
 122 //     if (normalTexture) {
 123 //       SGPath normalPath(path);
 124 //       normalPath.append(normalTexture);
 125 //       stateSet->setTextureAttribute(2, SGLoadTexture2D(normalPath));
 126 //       stateSet->setTextureMode(2, GL_TEXTURE_2D, osg::StateAttribute::ON);
 127 //     }
 128
 129     return stateSet;
 130 }
 131
 132 // Constructor
 133 SGCloudLayer::SGCloudLayer( const string &tex_path ) :
 134     cloud_root(new osg::Switch),
 135     layer_root(new osg::Switch),
 136     group_top(new osg::Group),
 137     group_bottom(new osg::Group),
 138     layer_transform(new osg::MatrixTransform),
 139     cloud_alpha(1.0),
 140     texture_path(tex_path),
 141     layer_span(0.0),
 142     layer_asl(0.0),
 143     layer_thickness(0.0),
 144     layer_transition(0.0),
 145     layer_visibility(25.0),
 146     layer_coverage(SG_CLOUD_CLEAR),
 147     scale(4000.0),
 148     speed(0.0),
 149     direction(0.0),
 150     last_course(0.0),
 151     max_alpha(1.0)
 152 {
 153     // XXX
 154     // Render bottoms before the rest of transparent objects (rendered
 155     // in bin 10), tops after. The negative numbers on the bottoms
 156     // RenderBins and the positive numbers on the tops enforce this
 157     // order.
 158   cloud_root->addChild(layer_root.get(), true);
 159   layer_root->addChild(group_bottom.get());
 160   layer_root->addChild(group_top.get());
 161   osg::StateSet *rootSet = layer_root->getOrCreateStateSet();
 162   rootSet->setRenderBinDetails(CLOUDS_BIN, "DepthSortedBin");
 163   rootSet->setTextureAttribute(0, new osg::TexMat);
 164   rootSet->setMode(GL_CULL_FACE, osg::StateAttribute::ON);
 165   // Combiner for fog color and cloud alpha
 166   osg::TexEnvCombine* combine0 = new osg::TexEnvCombine;
 167   osg::TexEnvCombine* combine1 = new osg::TexEnvCombine;
 168   combine0->setCombine_RGB(osg::TexEnvCombine::MODULATE);
 169   combine0->setSource0_RGB(osg::TexEnvCombine::PREVIOUS);
 170   combine0->setOperand0_RGB(osg::TexEnvCombine::SRC_COLOR);
 171   combine0->setSource1_RGB(osg::TexEnvCombine::TEXTURE0);
 172   combine0->setOperand1_RGB(osg::TexEnvCombine::SRC_COLOR);
 173   combine0->setCombine_Alpha(osg::TexEnvCombine::MODULATE);
 174   combine0->setSource0_Alpha(osg::TexEnvCombine::PREVIOUS);
 175   combine0->setOperand0_Alpha(osg::TexEnvCombine::SRC_ALPHA);
 176   combine0->setSource1_Alpha(osg::TexEnvCombine::TEXTURE0);
 177   combine0->setOperand1_Alpha(osg::TexEnvCombine::SRC_ALPHA);
 178
 179   combine1->setCombine_RGB(osg::TexEnvCombine::MODULATE);
 180   combine1->setSource0_RGB(osg::TexEnvCombine::PREVIOUS);
 181   combine1->setOperand0_RGB(osg::TexEnvCombine::SRC_COLOR);
 182   combine1->setSource1_RGB(osg::TexEnvCombine::CONSTANT);
 183   combine1->setOperand1_RGB(osg::TexEnvCombine::SRC_COLOR);
 184   combine1->setCombine_Alpha(osg::TexEnvCombine::MODULATE);
 185   combine1->setSource0_Alpha(osg::TexEnvCombine::PREVIOUS);
 186   combine1->setOperand0_Alpha(osg::TexEnvCombine::SRC_ALPHA);
 187   combine1->setSource1_Alpha(osg::TexEnvCombine::CONSTANT);
 188   combine1->setOperand1_Alpha(osg::TexEnvCombine::SRC_ALPHA);
 189   combine1->setDataVariance(osg::Object::DYNAMIC);
 190   rootSet->setTextureAttributeAndModes(0, combine0);
 191   rootSet->setTextureAttributeAndModes(1, combine1);
 192   rootSet->setTextureMode(1, GL_TEXTURE_2D, osg::StateAttribute::ON);
 193   rootSet->setTextureAttributeAndModes(1, StateAttributeFactory::instance()
 194                                        ->getWhiteTexture(),
 195                                        osg::StateAttribute::ON);
 196   rootSet->setDataVariance(osg::Object::DYNAMIC);
 197
 198   // Ensure repeatability of the random seed within 10 minutes,
 199   // to keep multi-computer systems in sync.
 200   sg_srandom_time_10();
 201   base = osg::Vec2(sg_random(), sg_random());
 202   group_top->addChild(layer_transform.get());
 203   group_bottom->addChild(layer_transform.get());
 204
 205   layer3D = new SGCloudField();
 206   cloud_root->addChild(layer3D->getNode(), false);
 207
 208   rebuild();
 209 }
 210
 211 // Destructor
 212 SGCloudLayer::~SGCloudLayer()
 213 {
 214   delete layer3D;
 215 }
 216
 217 float
 218 SGCloudLayer::getSpan_m () const
 219 {
 220     return layer_span;
 221 }
 222
 223 void
 224 SGCloudLayer::setSpan_m (float span_m)
 225 {
 226     if (span_m != layer_span) {
 227         layer_span = span_m;
 228         rebuild();
 229     }
 230 }
 231
 232 float
 233 SGCloudLayer::getElevation_m () const
 234 {
 235     return layer_asl;
 236 }
 237
 238 void
 239 SGCloudLayer::setElevation_m (float elevation_m, bool set_span)
 240 {
 241     layer_asl = elevation_m;
 242
 243     if (set_span) {
 244         if (elevation_m > 4000)
 245             setSpan_m(  elevation_m * 10 );
 246         else
 247             setSpan_m( 40000 );
 248     }
 249 }
 250
 251 float
 252 SGCloudLayer::getThickness_m () const
 253 {
 254     return layer_thickness;
 255 }
 256
 257 void
 258 SGCloudLayer::setThickness_m (float thickness_m)
 259 {
 260     layer_thickness = thickness_m;
 261 }
 262
 263 float
 264 SGCloudLayer::getVisibility_m() const
 265 {
 266     return layer_visibility;
 267 }
 268
 269 void
 270 SGCloudLayer::setVisibility_m (float visibility_m)
 271 {
 272     layer_visibility = visibility_m;
 273 }
 274
 275 float
 276 SGCloudLayer::getTransition_m () const
 277 {
 278     return layer_transition;
 279 }
 280
 281 void
 282 SGCloudLayer::setTransition_m (float transition_m)
 283 {
 284     layer_transition = transition_m;
 285 }
 286
 287 SGCloudLayer::Coverage
 288 SGCloudLayer::getCoverage () const
 289 {
 290     return layer_coverage;
 291 }
 292
 293 void
 294 SGCloudLayer::setCoverage (Coverage coverage)
 295 {
 296     if (coverage != layer_coverage) {
 297         layer_coverage = coverage;
 298         rebuild();
 299     }
 300 }
 301
 302 const std::string &
 303 SGCloudLayer::getCoverageString( Coverage coverage )
 304 {
 305         switch( coverage ) {
 306                 case SG_CLOUD_OVERCAST:
 307                         return SG_CLOUD_OVERCAST_STRING;
 308                 case SG_CLOUD_BROKEN:
 309                         return SG_CLOUD_BROKEN_STRING;
 310                 case SG_CLOUD_SCATTERED:
 311                         return SG_CLOUD_SCATTERED_STRING;
 312                 case SG_CLOUD_FEW:
 313                         return SG_CLOUD_FEW_STRING;
 314                 case SG_CLOUD_CIRRUS:
 315                         return SG_CLOUD_CIRRUS_STRING;
 316                 case SG_CLOUD_CLEAR:
 317                 default:
 318                         return SG_CLOUD_CLEAR_STRING;
 319         }
 320 }
 321
 322 SGCloudLayer::Coverage
 323 SGCloudLayer::getCoverageType( const std::string & coverage )
 324 {
 325         if( SG_CLOUD_OVERCAST_STRING == coverage ) {
 326                 return SG_CLOUD_OVERCAST;
 327         } else if( SG_CLOUD_BROKEN_STRING == coverage ) {
 328                 return SG_CLOUD_BROKEN;
 329         } else if( SG_CLOUD_SCATTERED_STRING == coverage ) {
 330                 return SG_CLOUD_SCATTERED;
 331         } else if( SG_CLOUD_FEW_STRING == coverage ) {
 332                 return SG_CLOUD_FEW;
 333         } else if( SG_CLOUD_CIRRUS_STRING == coverage ) {
 334                 return SG_CLOUD_CIRRUS;
 335         } else {
 336                 return SG_CLOUD_CLEAR;
 337         }
 338 }
 339
 340 const std::string &
 341 SGCloudLayer::getCoverageString() const
 342 {
 343         return getCoverageString(layer_coverage);
 344 }
 345
 346 void
 347 SGCloudLayer::setCoverageString( const std::string & coverage )
 348 {
 349         setCoverage( getCoverageType(coverage) );
 350 }
 351
 352 void
 353 SGCloudLayer::setTextureOffset(const osg::Vec2& offset)
 354 {
 355     osg::StateAttribute* attr = layer_root->getStateSet()
 356         ->getTextureAttribute(0, osg::StateAttribute::TEXMAT);
 357     osg::TexMat* texMat = dynamic_cast<osg::TexMat*>(attr);
 358     if (!texMat)
 359         return;
 360     texMat->setMatrix(osg::Matrix::translate(offset[0], offset[1], 0.0));
 361 }
 362
 363 // colors for debugging the cloud layers
 364 #ifdef CLOUD_DEBUG
 365 Vec3 cloudColors[] = {Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 0.0f, 0.0f),
 366                       Vec3(0.0f, 1.0f, 0.0f), Vec3(0.0f, 0.0f, 1.0f)};
 367 #else
 368 Vec3 cloudColors[] = {Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 1.0f, 1.0f),
 369                       Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 1.0f, 1.0f)};
 370 #endif
 371
 372 // build the cloud object
 373 void
 374 SGCloudLayer::rebuild()
 375 {
 376     // Initialize states and sizes if necessary.
 377     if ( !state_initialized ) {
 378         state_initialized = true;
 379
 380         SG_LOG(SG_ASTRO, SG_INFO, "initializing cloud layers");
 381
 382         // This bump mapping code was inspired by the tutorial available at
 383         // http://www.paulsprojects.net/tutorials/simplebump/simplebump.html
 384         // and a NVidia white paper
 385         //  http://developer.nvidia.com/object/bumpmappingwithregistercombiners.html
 386         // The normal map textures were generated by the normal map Gimp plugin :
 387         //  http://nifelheim.dyndns.org/~cocidius/normalmap/
 388         //
 389         cubeMap = new osg::TextureCubeMap;
 390         cubeMap->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
 391         cubeMap->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
 392         cubeMap->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
 393         cubeMap->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
 394         cubeMap->setWrap(osg::Texture::WRAP_R, osg::Texture::CLAMP_TO_EDGE);
 395
 396         const int size = 32;
 397         const float half_size = 16.0f;
 398         const float offset = 0.5f;
 399         osg::Vec3 zero_normal(0.5, 0.5, 0.5);
 400
 401         osg::Image* image = new osg::Image;
 402         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 403         unsigned char *ptr = image->data(0, 0);
 404         for (int j = 0; j < size; j++ ) {
 405           for (int i = 0; i < size; i++ ) {
 406             osg::Vec3 tmp(half_size, -( j + offset - half_size ),
 407                           -( i + offset - half_size ) );
 408             tmp.normalize();
 409             tmp = tmp*0.5 - zero_normal;
 410
 411             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 412             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 413             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 414           }
 415         }
 416         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_X, image);
 417
 418         image = new osg::Image;
 419         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 420         ptr = image->data(0, 0);
 421         for (int j = 0; j < size; j++ ) {
 422           for (int i = 0; i < size; i++ ) {
 423             osg::Vec3 tmp(-half_size, -( j + offset - half_size ),
 424                           ( i + offset - half_size ) );
 425             tmp.normalize();
 426             tmp = tmp*0.5 - zero_normal;
 427
 428             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 429             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 430             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 431           }
 432         }
 433         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_X, image);
 434
 435         image = new osg::Image;
 436         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 437         ptr = image->data(0, 0);
 438         for (int j = 0; j < size; j++ ) {
 439           for (int i = 0; i < size; i++ ) {
 440             osg::Vec3 tmp(( i + offset - half_size ), half_size,
 441                           ( j + offset - half_size ) );
 442             tmp.normalize();
 443             tmp = tmp*0.5 - zero_normal;
 444
 445             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 446             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 447             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 448           }
 449         }
 450         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Y, image);
 451
 452         image = new osg::Image;
 453         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 454         ptr = image->data(0, 0);
 455         for (int j = 0; j < size; j++ ) {
 456           for (int i = 0; i < size; i++ ) {
 457             osg::Vec3 tmp(( i + offset - half_size ), -half_size,
 458                           -( j + offset - half_size ) );
 459             tmp.normalize();
 460             tmp = tmp*0.5 - zero_normal;
 461
 462             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 463             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 464             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 465           }
 466         }
 467         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Y, image);
 468
 469         image = new osg::Image;
 470         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 471         ptr = image->data(0, 0);
 472         for (int j = 0; j < size; j++ ) {
 473           for (int i = 0; i < size; i++ ) {
 474             osg::Vec3 tmp(( i + offset - half_size ),
 475                           -( j + offset - half_size ), half_size );
 476             tmp.normalize();
 477             tmp = tmp*0.5 - zero_normal;
 478
 479             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 480             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 481             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 482           }
 483         }
 484         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Z, image);
 485
 486         image = new osg::Image;
 487         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 488         ptr = image->data(0, 0);
 489         for (int j = 0; j < size; j++ ) {
 490           for (int i = 0; i < size; i++ ) {
 491             osg::Vec3 tmp(-( i + offset - half_size ),
 492                           -( j + offset - half_size ), -half_size );
 493             tmp.normalize();
 494             tmp = tmp*0.5 - zero_normal;
 495             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 496             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 497             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 498           }
 499         }
 500         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Z, image);
 501
 502         osg::StateSet* state;
 503         state = SGMakeState(texture_path, "overcast.png", "overcast_n.png");
 504         layer_states[SG_CLOUD_OVERCAST] = state;
 505         state = SGMakeState(texture_path, "overcast_top.png", "overcast_top_n.png");
 506         layer_states2[SG_CLOUD_OVERCAST] = state;
 507
 508         state = SGMakeState(texture_path, "broken.png", "broken_n.png");
 509         layer_states[SG_CLOUD_BROKEN] = state;
 510         layer_states2[SG_CLOUD_BROKEN] = state;
 511
 512         state = SGMakeState(texture_path, "scattered.png", "scattered_n.png");
 513         layer_states[SG_CLOUD_SCATTERED] = state;
 514         layer_states2[SG_CLOUD_SCATTERED] = state;
 515
 516         state = SGMakeState(texture_path, "few.png", "few_n.png");
 517         layer_states[SG_CLOUD_FEW] = state;
 518         layer_states2[SG_CLOUD_FEW] = state;
 519
 520         state = SGMakeState(texture_path, "cirrus.png", "cirrus_n.png");
 521         layer_states[SG_CLOUD_CIRRUS] = state;
 522         layer_states2[SG_CLOUD_CIRRUS] = state;
 523
 524         layer_states[SG_CLOUD_CLEAR] = 0;
 525         layer_states2[SG_CLOUD_CLEAR] = 0;
 526 #if 1
 527         // experimental optimization that may not make any difference
 528         // at all :/
 529         osg::CopyOp copyOp;
 530         for (int i = 0; i < SG_MAX_CLOUD_COVERAGES; ++i) {
 531             StateAttributeFactory *saf = StateAttributeFactory::instance();
 532             if (layer_states[i].valid()) {
 533                 if (layer_states[i] == layer_states2[i])
 534                     layer_states2[i] = static_cast<osg::StateSet*>(layer_states[i]->clone(copyOp));
 535                 layer_states[i]->setAttribute(saf ->getCullFaceFront());
 536                 layer_states2[i]->setAttribute(saf ->getCullFaceBack());
 537             }
 538         }
 539 #endif
 540     }
 541
 542     scale = 4000.0;
 543
 544     setTextureOffset(base);
 545     // build the cloud layer
 546     const float layer_scale = layer_span / scale;
 547     const float mpi = SG_PI/4;
 548
 549     // caclculate the difference between a flat-earth model and
 550     // a round earth model given the span and altutude ASL of
 551     // the cloud layer. This is the difference in altitude between
 552     // the top of the inverted bowl and the edge of the bowl.
 553     // const float alt_diff = layer_asl * 0.8;
 554     const float layer_to_core = (SG_EARTH_RAD * 1000 + layer_asl);
 555     const float layer_angle = 0.5*layer_span / layer_to_core; // The angle is half the span
 556     const float border_to_core = layer_to_core * cos(layer_angle);
 557     const float alt_diff = layer_to_core - border_to_core;
 558
 559     for (int i = 0; i < 4; i++) {
 560       if ( layer[i] != NULL ) {
 561         layer_transform->removeChild(layer[i].get()); // automatic delete
 562       }
 563
 564       vl[i] = new osg::Vec3Array;
 565       cl[i] = new osg::Vec4Array;
 566       tl[i] = new osg::Vec2Array;
 567
 568
 569       osg::Vec3 vertex(layer_span*(i-2)/2, -layer_span,
 570                        alt_diff * (sin(i*mpi) - 2));
 571       osg::Vec2 tc(layer_scale * i/4, 0.0f);
 572       osg::Vec4 color(cloudColors[0], (i == 0) ? 0.0f : 0.15f);
 573
 574       cl[i]->push_back(color);
 575       vl[i]->push_back(vertex);
 576       tl[i]->push_back(tc);
 577
 578       for (int j = 0; j < 4; j++) {
 579         vertex = osg::Vec3(layer_span*(i-1)/2, layer_span*(j-2)/2,
 580                            alt_diff * (sin((i+1)*mpi) + sin(j*mpi) - 2));
 581         tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale * j/4);
 582         color = osg::Vec4(cloudColors[0],
 583                           ( (j == 0) || (i == 3)) ?
 584                           ( (j == 0) && (i == 3)) ? 0.0f : 0.15f : 1.0f );
 585
 586         cl[i]->push_back(color);
 587         vl[i]->push_back(vertex);
 588         tl[i]->push_back(tc);
 589
 590         vertex = osg::Vec3(layer_span*(i-2)/2, layer_span*(j-1)/2,
 591                            alt_diff * (sin(i*mpi) + sin((j+1)*mpi) - 2) );
 592         tc = osg::Vec2(layer_scale * i/4, layer_scale * (j+1)/4 );
 593         color = osg::Vec4(cloudColors[0],
 594                           ((j == 3) || (i == 0)) ?
 595                           ((j == 3) && (i == 0)) ? 0.0f : 0.15f : 1.0f );
 596         cl[i]->push_back(color);
 597         vl[i]->push_back(vertex);
 598         tl[i]->push_back(tc);
 599       }
 600
 601       vertex = osg::Vec3(layer_span*(i-1)/2, layer_span,
 602                          alt_diff * (sin((i+1)*mpi) - 2));
 603
 604       tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale);
 605
 606       color = osg::Vec4(cloudColors[0], (i == 3) ? 0.0f : 0.15f );
 607
 608       cl[i]->push_back( color );
 609       vl[i]->push_back( vertex );
 610       tl[i]->push_back( tc );
 611
 612       osg::Geometry* geometry = new osg::Geometry;
 613       geometry->setUseDisplayList(false);
 614       geometry->setVertexArray(vl[i].get());
 615       geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 616       geometry->setColorArray(cl[i].get());
 617       geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 618       geometry->setTexCoordArray(0, tl[i].get());
 619       geometry->addPrimitiveSet(new osg::DrawArrays(GL_TRIANGLE_STRIP, 0, vl[i]->size()));
 620       layer[i] = new osg::Geode;
 621
 622       std::stringstream sstr;
 623       sstr << "Cloud Layer (" << i << ")";
 624       geometry->setName(sstr.str());
 625       layer[i]->setName(sstr.str());
 626       layer[i]->addDrawable(geometry);
 627       layer_transform->addChild(layer[i].get());
 628     }
 629
 630     //OSGFIXME: true
 631     if ( layer_states[layer_coverage].valid() ) {
 632       osg::CopyOp copyOp;    // shallow copy
 633       // render bin will be set in reposition
 634       osg::StateSet* stateSet = static_cast<osg::StateSet*>(layer_states2[layer_coverage]->clone(copyOp));
 635       stateSet->setDataVariance(osg::Object::DYNAMIC);
 636       group_top->setStateSet(stateSet);
 637       stateSet = static_cast<osg::StateSet*>(layer_states[layer_coverage]->clone(copyOp));
 638       stateSet->setDataVariance(osg::Object::DYNAMIC);
 639       group_bottom->setStateSet(stateSet);
 640     }
 641 }
 642
 643 // repaint the cloud layer colors
 644 bool SGCloudLayer::repaint( const SGVec3f& fog_color ) {
 645     osg::Vec4f combineColor(toOsg(fog_color), cloud_alpha);
 646     osg::TexEnvCombine* combiner
 647         = dynamic_cast<osg::TexEnvCombine*>(layer_root->getStateSet()
 648                                             ->getTextureAttribute(1, osg::StateAttribute::TEXENV));
 649     combiner->setConstantColor(combineColor);
 650
 651     // Set the fog color for the 3D clouds too.
 652     //cloud3dfog->setColor(combineColor);
 653     return true;
 654 }
 655
 656 // reposition the cloud layer at the specified origin and orientation
 657 // lon specifies a rotation about the Z axis
 658 // lat specifies a rotation about the new Y axis
 659 // spin specifies a rotation about the new Z axis (and orients the
 660 // sunrise/set effects
 661 bool SGCloudLayer::reposition( const SGVec3f& p, const SGVec3f& up, double lon, double lat,
 662                                double alt, double dt )
 663 {
 664
 665     if (getCoverage() != SGCloudLayer::SG_CLOUD_CLEAR)
 666     {
 667         // combine p and asl (meters) to get translation offset
 668         osg::Vec3 asl_offset(toOsg(up));
 669         asl_offset.normalize();
 670         if ( alt <= layer_asl ) {
 671             asl_offset *= layer_asl;
 672         } else {
 673             asl_offset *= layer_asl + layer_thickness;
 674         }
 675
 676         // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 677         //      << "," << asl_offset[2] << endl;
 678         asl_offset += toOsg(p);
 679         // cout << "  asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 680         //      << "," << asl_offset[2] << endl;
 681
 682         osg::Matrix T, LON, LAT;
 683         // Translate to zero elevation
 684         // Point3D zero_elev = current_view.get_cur_zero_elev();
 685         T.makeTranslate( asl_offset );
 686
 687         // printf("  Translated to %.2f %.2f %.2f\n",
 688         //        zero_elev.x, zero_elev.y, zero_elev.z );
 689
 690         // Rotate to proper orientation
 691         // printf("  lon = %.2f  lat = %.2f\n",
 692         //        lon * SGD_RADIANS_TO_DEGREES,
 693         //        lat * SGD_RADIANS_TO_DEGREES);
 694         LON.makeRotate(lon, osg::Vec3(0, 0, 1));
 695
 696         // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
 697         //             0.0, 1.0, 0.0 );
 698         LAT.makeRotate(90.0 * SGD_DEGREES_TO_RADIANS - lat, osg::Vec3(0, 1, 0));
 699
 700         layer_transform->setMatrix( LAT*LON*T );
 701
 702         // The layers need to be drawn in order because they are
 703         // translucent, but OSG transparency sorting doesn't work because
 704         // the cloud polys are huge. However, the ordering is simple: the
 705         // bottom polys should be drawn from high altitude to low, and the
 706         // top polygons from low to high. The altitude can be used
 707         // directly to order the polygons!
 708         group_bottom->getStateSet()->setRenderBinDetails(-(int)layer_asl,
 709                                                          "RenderBin");
 710         group_top->getStateSet()->setRenderBinDetails((int)layer_asl,
 711                                                       "RenderBin");
 712         if ( alt <= layer_asl ) {
 713           layer_root->setSingleChildOn(0);
 714         } else if ( alt >= layer_asl + layer_thickness ) {
 715           layer_root->setSingleChildOn(1);
 716         } else {
 717           layer_root->setAllChildrenOff();
 718         }
 719
 720
 721         // now calculate update texture coordinates
 722         SGGeod pos = SGGeod::fromRad(lon, lat);
 723         if ( last_pos == SGGeod() ) {
 724             last_pos = pos;
 725         }
 726
 727         double sp_dist = speed*dt;
 728
 729
 730         if ( lon != last_pos.getLongitudeRad() || lat != last_pos.getLatitudeRad() || sp_dist != 0 ) {
 731             double course = SGGeodesy::courseDeg(last_pos, pos) * SG_DEGREES_TO_RADIANS,
 732                 dist = SGGeodesy::distanceM(last_pos, pos);
 733
 734             // if start and dest are too close together,
 735             // calc_gc_course_dist() can return a course of "nan".  If
 736             // this happens, lets just use the last known good course.
 737             // This is a hack, and it would probably be better to make
 738             // calc_gc_course_dist() more robust.
 739             if ( isnan(course) ) {
 740                 course = last_course;
 741             } else {
 742                 last_course = course;
 743             }
 744
 745             // calculate cloud movement due to external forces
 746             double ax = 0.0, ay = 0.0, bx = 0.0, by = 0.0;
 747
 748             if (dist > 0.0) {
 749                 ax = -cos(course) * dist;
 750                 ay = sin(course) * dist;
 751             }
 752
 753             if (sp_dist > 0) {
 754                 bx = cos((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 755                 by = sin((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 756             }
 757
 758
 759             double xoff = (ax + bx) / (2 * scale);
 760             double yoff = (ay + by) / (2 * scale);
 761
 762
 763     //        const float layer_scale = layer_span / scale;
 764
 765             // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
 766             base[0] += xoff;
 767
 768             // the while loops can lead to *long* pauses if base[0] comes
 769             // with a bogus value.
 770             // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
 771             // while ( base[0] < 0.0 ) { base[0] += 1.0; }
 772             if ( base[0] > -10.0 && base[0] < 10.0 ) {
 773                 base[0] -= (int)base[0];
 774             } else {
 775                 SG_LOG(SG_ASTRO, SG_DEBUG,
 776                     "Error: base = " << base[0] << "," << base[1] <<
 777                     " course = " << course << " dist = " << dist );
 778                 base[0] = 0.0;
 779             }
 780
 781             base[1] += yoff;
 782             // the while loops can lead to *long* pauses if base[0] comes
 783             // with a bogus value.
 784             // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
 785             // while ( base[1] < 0.0 ) { base[1] += 1.0; }
 786             if ( base[1] > -10.0 && base[1] < 10.0 ) {
 787                 base[1] -= (int)base[1];
 788             } else {
 789                 SG_LOG(SG_ASTRO, SG_DEBUG,
 790                         "Error: base = " << base[0] << "," << base[1] <<
 791                         " course = " << course << " dist = " << dist );
 792                 base[1] = 0.0;
 793             }
 794
 795             // cout << "base = " << base[0] << "," << base[1] << endl;
 796
 797             setTextureOffset(base);
 798             last_pos = pos;
 799         }
 800     }
 801
 802     layer3D->reposition( p, up, lon, lat, dt, layer_asl, speed, direction);
 803     return true;
 804 }
 805
 806 void SGCloudLayer::set_enable3dClouds(bool enable) {
 807
 808     if (layer3D->isDefined3D() && enable) {
 809         cloud_root->setChildValue(layer3D->getNode(), true);
 810         cloud_root->setChildValue(layer_root.get(),   false);
 811     } else {
 812         cloud_root->setChildValue(layer3D->getNode(), false);
 813         cloud_root->setChildValue(layer_root.get(),   true);
 814     }
 815 }