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   base = osg::Vec2(sg_random(), sg_random());
 199   group_top->addChild(layer_transform.get());
 200   group_bottom->addChild(layer_transform.get());
 201
 202   layer3D = new SGCloudField();
 203   cloud_root->addChild(layer3D->getNode(), false);
 204
 205   rebuild();
 206 }
 207
 208 // Destructor
 209 SGCloudLayer::~SGCloudLayer()
 210 {
 211   delete layer3D;
 212 }
 213
 214 float
 215 SGCloudLayer::getSpan_m () const
 216 {
 217     return layer_span;
 218 }
 219
 220 void
 221 SGCloudLayer::setSpan_m (float span_m)
 222 {
 223     if (span_m != layer_span) {
 224         layer_span = span_m;
 225         rebuild();
 226     }
 227 }
 228
 229 float
 230 SGCloudLayer::getElevation_m () const
 231 {
 232     return layer_asl;
 233 }
 234
 235 void
 236 SGCloudLayer::setElevation_m (float elevation_m, bool set_span)
 237 {
 238     layer_asl = elevation_m;
 239
 240     if (set_span) {
 241         if (elevation_m > 4000)
 242             setSpan_m(  elevation_m * 10 );
 243         else
 244             setSpan_m( 40000 );
 245     }
 246 }
 247
 248 float
 249 SGCloudLayer::getThickness_m () const
 250 {
 251     return layer_thickness;
 252 }
 253
 254 void
 255 SGCloudLayer::setThickness_m (float thickness_m)
 256 {
 257     layer_thickness = thickness_m;
 258 }
 259
 260 float
 261 SGCloudLayer::getVisibility_m() const
 262 {
 263     return layer_visibility;
 264 }
 265
 266 void
 267 SGCloudLayer::setVisibility_m (float visibility_m)
 268 {
 269     layer_visibility = visibility_m;
 270 }
 271
 272 float
 273 SGCloudLayer::getTransition_m () const
 274 {
 275     return layer_transition;
 276 }
 277
 278 void
 279 SGCloudLayer::setTransition_m (float transition_m)
 280 {
 281     layer_transition = transition_m;
 282 }
 283
 284 SGCloudLayer::Coverage
 285 SGCloudLayer::getCoverage () const
 286 {
 287     return layer_coverage;
 288 }
 289
 290 void
 291 SGCloudLayer::setCoverage (Coverage coverage)
 292 {
 293     if (coverage != layer_coverage) {
 294         layer_coverage = coverage;
 295         rebuild();
 296     }
 297 }
 298
 299 const std::string &
 300 SGCloudLayer::getCoverageString( Coverage coverage )
 301 {
 302         switch( coverage ) {
 303                 case SG_CLOUD_OVERCAST:
 304                         return SG_CLOUD_OVERCAST_STRING;
 305                 case SG_CLOUD_BROKEN:
 306                         return SG_CLOUD_BROKEN_STRING;
 307                 case SG_CLOUD_SCATTERED:
 308                         return SG_CLOUD_SCATTERED_STRING;
 309                 case SG_CLOUD_FEW:
 310                         return SG_CLOUD_FEW_STRING;
 311                 case SG_CLOUD_CIRRUS:
 312                         return SG_CLOUD_CIRRUS_STRING;
 313                 case SG_CLOUD_CLEAR:
 314                 default:
 315                         return SG_CLOUD_CLEAR_STRING;
 316         }
 317 }
 318
 319 SGCloudLayer::Coverage
 320 SGCloudLayer::getCoverageType( const std::string & coverage )
 321 {
 322         if( SG_CLOUD_OVERCAST_STRING == coverage ) {
 323                 return SG_CLOUD_OVERCAST;
 324         } else if( SG_CLOUD_BROKEN_STRING == coverage ) {
 325                 return SG_CLOUD_BROKEN;
 326         } else if( SG_CLOUD_SCATTERED_STRING == coverage ) {
 327                 return SG_CLOUD_SCATTERED;
 328         } else if( SG_CLOUD_FEW_STRING == coverage ) {
 329                 return SG_CLOUD_FEW;
 330         } else if( SG_CLOUD_CIRRUS_STRING == coverage ) {
 331                 return SG_CLOUD_CIRRUS;
 332         } else {
 333                 return SG_CLOUD_CLEAR;
 334         }
 335 }
 336
 337 const std::string &
 338 SGCloudLayer::getCoverageString() const
 339 {
 340         return getCoverageString(layer_coverage);
 341 }
 342
 343 void
 344 SGCloudLayer::setCoverageString( const std::string & coverage )
 345 {
 346         setCoverage( getCoverageType(coverage) );
 347 }
 348
 349 void
 350 SGCloudLayer::setTextureOffset(const osg::Vec2& offset)
 351 {
 352     osg::StateAttribute* attr = layer_root->getStateSet()
 353         ->getTextureAttribute(0, osg::StateAttribute::TEXMAT);
 354     osg::TexMat* texMat = dynamic_cast<osg::TexMat*>(attr);
 355     if (!texMat)
 356         return;
 357     texMat->setMatrix(osg::Matrix::translate(offset[0], offset[1], 0.0));
 358 }
 359
 360 // colors for debugging the cloud layers
 361 #ifdef CLOUD_DEBUG
 362 Vec3 cloudColors[] = {Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 0.0f, 0.0f),
 363                       Vec3(0.0f, 1.0f, 0.0f), Vec3(0.0f, 0.0f, 1.0f)};
 364 #else
 365 Vec3 cloudColors[] = {Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 1.0f, 1.0f),
 366                       Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 1.0f, 1.0f)};
 367 #endif
 368
 369 // build the cloud object
 370 void
 371 SGCloudLayer::rebuild()
 372 {
 373     // Initialize states and sizes if necessary.
 374     if ( !state_initialized ) {
 375         state_initialized = true;
 376
 377         SG_LOG(SG_ASTRO, SG_INFO, "initializing cloud layers");
 378
 379         // This bump mapping code was inspired by the tutorial available at
 380         // http://www.paulsprojects.net/tutorials/simplebump/simplebump.html
 381         // and a NVidia white paper
 382         //  http://developer.nvidia.com/object/bumpmappingwithregistercombiners.html
 383         // The normal map textures were generated by the normal map Gimp plugin :
 384         //  http://nifelheim.dyndns.org/~cocidius/normalmap/
 385         //
 386         cubeMap = new osg::TextureCubeMap;
 387         cubeMap->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
 388         cubeMap->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
 389         cubeMap->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
 390         cubeMap->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
 391         cubeMap->setWrap(osg::Texture::WRAP_R, osg::Texture::CLAMP_TO_EDGE);
 392
 393         const int size = 32;
 394         const float half_size = 16.0f;
 395         const float offset = 0.5f;
 396         osg::Vec3 zero_normal(0.5, 0.5, 0.5);
 397
 398         osg::Image* image = new osg::Image;
 399         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 400         unsigned char *ptr = image->data(0, 0);
 401         for (int j = 0; j < size; j++ ) {
 402           for (int i = 0; i < size; i++ ) {
 403             osg::Vec3 tmp(half_size, -( j + offset - half_size ),
 404                           -( i + offset - half_size ) );
 405             tmp.normalize();
 406             tmp = tmp*0.5 - zero_normal;
 407
 408             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 409             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 410             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 411           }
 412         }
 413         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_X, image);
 414
 415         image = new osg::Image;
 416         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 417         ptr = image->data(0, 0);
 418         for (int j = 0; j < size; j++ ) {
 419           for (int i = 0; i < size; i++ ) {
 420             osg::Vec3 tmp(-half_size, -( j + offset - half_size ),
 421                           ( i + offset - half_size ) );
 422             tmp.normalize();
 423             tmp = tmp*0.5 - zero_normal;
 424
 425             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 426             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 427             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 428           }
 429         }
 430         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_X, image);
 431
 432         image = new osg::Image;
 433         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 434         ptr = image->data(0, 0);
 435         for (int j = 0; j < size; j++ ) {
 436           for (int i = 0; i < size; i++ ) {
 437             osg::Vec3 tmp(( i + offset - half_size ), half_size,
 438                           ( j + offset - half_size ) );
 439             tmp.normalize();
 440             tmp = tmp*0.5 - zero_normal;
 441
 442             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 443             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 444             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 445           }
 446         }
 447         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Y, image);
 448
 449         image = new osg::Image;
 450         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 451         ptr = image->data(0, 0);
 452         for (int j = 0; j < size; j++ ) {
 453           for (int i = 0; i < size; i++ ) {
 454             osg::Vec3 tmp(( i + offset - half_size ), -half_size,
 455                           -( j + offset - half_size ) );
 456             tmp.normalize();
 457             tmp = tmp*0.5 - zero_normal;
 458
 459             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 460             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 461             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 462           }
 463         }
 464         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Y, image);
 465
 466         image = new osg::Image;
 467         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 468         ptr = image->data(0, 0);
 469         for (int j = 0; j < size; j++ ) {
 470           for (int i = 0; i < size; i++ ) {
 471             osg::Vec3 tmp(( i + offset - half_size ),
 472                           -( j + offset - half_size ), half_size );
 473             tmp.normalize();
 474             tmp = tmp*0.5 - zero_normal;
 475
 476             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 477             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 478             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 479           }
 480         }
 481         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Z, image);
 482
 483         image = new osg::Image;
 484         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 485         ptr = image->data(0, 0);
 486         for (int j = 0; j < size; j++ ) {
 487           for (int i = 0; i < size; i++ ) {
 488             osg::Vec3 tmp(-( i + offset - half_size ),
 489                           -( j + offset - half_size ), -half_size );
 490             tmp.normalize();
 491             tmp = tmp*0.5 - zero_normal;
 492             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 493             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 494             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 495           }
 496         }
 497         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Z, image);
 498
 499         osg::StateSet* state;
 500         state = SGMakeState(texture_path, "overcast.png", "overcast_n.png");
 501         layer_states[SG_CLOUD_OVERCAST] = state;
 502         state = SGMakeState(texture_path, "overcast_top.png", "overcast_top_n.png");
 503         layer_states2[SG_CLOUD_OVERCAST] = state;
 504
 505         state = SGMakeState(texture_path, "broken.png", "broken_n.png");
 506         layer_states[SG_CLOUD_BROKEN] = state;
 507         layer_states2[SG_CLOUD_BROKEN] = state;
 508
 509         state = SGMakeState(texture_path, "scattered.png", "scattered_n.png");
 510         layer_states[SG_CLOUD_SCATTERED] = state;
 511         layer_states2[SG_CLOUD_SCATTERED] = state;
 512
 513         state = SGMakeState(texture_path, "few.png", "few_n.png");
 514         layer_states[SG_CLOUD_FEW] = state;
 515         layer_states2[SG_CLOUD_FEW] = state;
 516
 517         state = SGMakeState(texture_path, "cirrus.png", "cirrus_n.png");
 518         layer_states[SG_CLOUD_CIRRUS] = state;
 519         layer_states2[SG_CLOUD_CIRRUS] = state;
 520
 521         layer_states[SG_CLOUD_CLEAR] = 0;
 522         layer_states2[SG_CLOUD_CLEAR] = 0;
 523 #if 1
 524         // experimental optimization that may not make any difference
 525         // at all :/
 526         osg::CopyOp copyOp;
 527         for (int i = 0; i < SG_MAX_CLOUD_COVERAGES; ++i) {
 528             StateAttributeFactory *saf = StateAttributeFactory::instance();
 529             if (layer_states[i].valid()) {
 530                 if (layer_states[i] == layer_states2[i])
 531                     layer_states2[i] = static_cast<osg::StateSet*>(layer_states[i]->clone(copyOp));
 532                 layer_states[i]->setAttribute(saf ->getCullFaceFront());
 533                 layer_states2[i]->setAttribute(saf ->getCullFaceBack());
 534             }
 535         }
 536 #endif
 537     }
 538
 539     scale = 4000.0;
 540
 541     setTextureOffset(base);
 542     // build the cloud layer
 543     const float layer_scale = layer_span / scale;
 544     const float mpi = SG_PI/4;
 545
 546     // caclculate the difference between a flat-earth model and
 547     // a round earth model given the span and altutude ASL of
 548     // the cloud layer. This is the difference in altitude between
 549     // the top of the inverted bowl and the edge of the bowl.
 550     // const float alt_diff = layer_asl * 0.8;
 551     const float layer_to_core = (SG_EARTH_RAD * 1000 + layer_asl);
 552     const float layer_angle = 0.5*layer_span / layer_to_core; // The angle is half the span
 553     const float border_to_core = layer_to_core * cos(layer_angle);
 554     const float alt_diff = layer_to_core - border_to_core;
 555
 556     for (int i = 0; i < 4; i++) {
 557       if ( layer[i] != NULL ) {
 558         layer_transform->removeChild(layer[i].get()); // automatic delete
 559       }
 560
 561       vl[i] = new osg::Vec3Array;
 562       cl[i] = new osg::Vec4Array;
 563       tl[i] = new osg::Vec2Array;
 564
 565
 566       osg::Vec3 vertex(layer_span*(i-2)/2, -layer_span,
 567                        alt_diff * (sin(i*mpi) - 2));
 568       osg::Vec2 tc(layer_scale * i/4, 0.0f);
 569       osg::Vec4 color(cloudColors[0], (i == 0) ? 0.0f : 0.15f);
 570
 571       cl[i]->push_back(color);
 572       vl[i]->push_back(vertex);
 573       tl[i]->push_back(tc);
 574
 575       for (int j = 0; j < 4; j++) {
 576         vertex = osg::Vec3(layer_span*(i-1)/2, layer_span*(j-2)/2,
 577                            alt_diff * (sin((i+1)*mpi) + sin(j*mpi) - 2));
 578         tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale * j/4);
 579         color = osg::Vec4(cloudColors[0],
 580                           ( (j == 0) || (i == 3)) ?
 581                           ( (j == 0) && (i == 3)) ? 0.0f : 0.15f : 1.0f );
 582
 583         cl[i]->push_back(color);
 584         vl[i]->push_back(vertex);
 585         tl[i]->push_back(tc);
 586
 587         vertex = osg::Vec3(layer_span*(i-2)/2, layer_span*(j-1)/2,
 588                            alt_diff * (sin(i*mpi) + sin((j+1)*mpi) - 2) );
 589         tc = osg::Vec2(layer_scale * i/4, layer_scale * (j+1)/4 );
 590         color = osg::Vec4(cloudColors[0],
 591                           ((j == 3) || (i == 0)) ?
 592                           ((j == 3) && (i == 0)) ? 0.0f : 0.15f : 1.0f );
 593         cl[i]->push_back(color);
 594         vl[i]->push_back(vertex);
 595         tl[i]->push_back(tc);
 596       }
 597
 598       vertex = osg::Vec3(layer_span*(i-1)/2, layer_span,
 599                          alt_diff * (sin((i+1)*mpi) - 2));
 600
 601       tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale);
 602
 603       color = osg::Vec4(cloudColors[0], (i == 3) ? 0.0f : 0.15f );
 604
 605       cl[i]->push_back( color );
 606       vl[i]->push_back( vertex );
 607       tl[i]->push_back( tc );
 608
 609       osg::Geometry* geometry = new osg::Geometry;
 610       geometry->setUseDisplayList(false);
 611       geometry->setVertexArray(vl[i].get());
 612       geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 613       geometry->setColorArray(cl[i].get());
 614       geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 615       geometry->setTexCoordArray(0, tl[i].get());
 616       geometry->addPrimitiveSet(new osg::DrawArrays(GL_TRIANGLE_STRIP, 0, vl[i]->size()));
 617       layer[i] = new osg::Geode;
 618
 619       std::stringstream sstr;
 620       sstr << "Cloud Layer (" << i << ")";
 621       geometry->setName(sstr.str());
 622       layer[i]->setName(sstr.str());
 623       layer[i]->addDrawable(geometry);
 624       layer_transform->addChild(layer[i].get());
 625     }
 626
 627     //OSGFIXME: true
 628     if ( layer_states[layer_coverage].valid() ) {
 629       osg::CopyOp copyOp;    // shallow copy
 630       // render bin will be set in reposition
 631       osg::StateSet* stateSet = static_cast<osg::StateSet*>(layer_states2[layer_coverage]->clone(copyOp));
 632       stateSet->setDataVariance(osg::Object::DYNAMIC);
 633       group_top->setStateSet(stateSet);
 634       stateSet = static_cast<osg::StateSet*>(layer_states[layer_coverage]->clone(copyOp));
 635       stateSet->setDataVariance(osg::Object::DYNAMIC);
 636       group_bottom->setStateSet(stateSet);
 637     }
 638 }
 639
 640 // repaint the cloud layer colors
 641 bool SGCloudLayer::repaint( const SGVec3f& fog_color ) {
 642     osg::Vec4f combineColor(toOsg(fog_color), cloud_alpha);
 643     osg::TexEnvCombine* combiner
 644         = dynamic_cast<osg::TexEnvCombine*>(layer_root->getStateSet()
 645                                             ->getTextureAttribute(1, osg::StateAttribute::TEXENV));
 646     combiner->setConstantColor(combineColor);
 647
 648     // Set the fog color for the 3D clouds too.
 649     //cloud3dfog->setColor(combineColor);
 650     return true;
 651 }
 652
 653 // reposition the cloud layer at the specified origin and orientation
 654 // lon specifies a rotation about the Z axis
 655 // lat specifies a rotation about the new Y axis
 656 // spin specifies a rotation about the new Z axis (and orients the
 657 // sunrise/set effects
 658 bool SGCloudLayer::reposition( const SGVec3f& p, const SGVec3f& up, double lon, double lat,
 659                                double alt, double dt )
 660 {
 661
 662     if (getCoverage() != SGCloudLayer::SG_CLOUD_CLEAR)
 663     {
 664         // combine p and asl (meters) to get translation offset
 665         osg::Vec3 asl_offset(toOsg(up));
 666         asl_offset.normalize();
 667         if ( alt <= layer_asl ) {
 668             asl_offset *= layer_asl;
 669         } else {
 670             asl_offset *= layer_asl + layer_thickness;
 671         }
 672
 673         // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 674         //      << "," << asl_offset[2] << endl;
 675         asl_offset += toOsg(p);
 676         // cout << "  asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 677         //      << "," << asl_offset[2] << endl;
 678
 679         osg::Matrix T, LON, LAT;
 680         // Translate to zero elevation
 681         // Point3D zero_elev = current_view.get_cur_zero_elev();
 682         T.makeTranslate( asl_offset );
 683
 684         // printf("  Translated to %.2f %.2f %.2f\n",
 685         //        zero_elev.x, zero_elev.y, zero_elev.z );
 686
 687         // Rotate to proper orientation
 688         // printf("  lon = %.2f  lat = %.2f\n",
 689         //        lon * SGD_RADIANS_TO_DEGREES,
 690         //        lat * SGD_RADIANS_TO_DEGREES);
 691         LON.makeRotate(lon, osg::Vec3(0, 0, 1));
 692
 693         // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
 694         //             0.0, 1.0, 0.0 );
 695         LAT.makeRotate(90.0 * SGD_DEGREES_TO_RADIANS - lat, osg::Vec3(0, 1, 0));
 696
 697         layer_transform->setMatrix( LAT*LON*T );
 698
 699         // The layers need to be drawn in order because they are
 700         // translucent, but OSG transparency sorting doesn't work because
 701         // the cloud polys are huge. However, the ordering is simple: the
 702         // bottom polys should be drawn from high altitude to low, and the
 703         // top polygons from low to high. The altitude can be used
 704         // directly to order the polygons!
 705         group_bottom->getStateSet()->setRenderBinDetails(-(int)layer_asl,
 706                                                          "RenderBin");
 707         group_top->getStateSet()->setRenderBinDetails((int)layer_asl,
 708                                                       "RenderBin");
 709         if ( alt <= layer_asl ) {
 710           layer_root->setSingleChildOn(0);
 711         } else if ( alt >= layer_asl + layer_thickness ) {
 712           layer_root->setSingleChildOn(1);
 713         } else {
 714           layer_root->setAllChildrenOff();
 715         }
 716
 717
 718         // now calculate update texture coordinates
 719         SGGeod pos = SGGeod::fromRad(lon, lat);
 720         if ( last_pos == SGGeod() ) {
 721             last_pos = pos;
 722         }
 723
 724         double sp_dist = speed*dt;
 725
 726
 727         if ( lon != last_pos.getLongitudeRad() || lat != last_pos.getLatitudeRad() || sp_dist != 0 ) {
 728             double course = SGGeodesy::courseDeg(last_pos, pos) * SG_DEGREES_TO_RADIANS,
 729                 dist = SGGeodesy::distanceM(last_pos, pos);
 730
 731             // if start and dest are too close together,
 732             // calc_gc_course_dist() can return a course of "nan".  If
 733             // this happens, lets just use the last known good course.
 734             // This is a hack, and it would probably be better to make
 735             // calc_gc_course_dist() more robust.
 736             if ( isnan(course) ) {
 737                 course = last_course;
 738             } else {
 739                 last_course = course;
 740             }
 741
 742             // calculate cloud movement due to external forces
 743             double ax = 0.0, ay = 0.0, bx = 0.0, by = 0.0;
 744
 745             if (dist > 0.0) {
 746                 ax = -cos(course) * dist;
 747                 ay = sin(course) * dist;
 748             }
 749
 750             if (sp_dist > 0) {
 751                 bx = cos((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 752                 by = sin((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 753             }
 754
 755
 756             double xoff = (ax + bx) / (2 * scale);
 757             double yoff = (ay + by) / (2 * scale);
 758
 759
 760     //        const float layer_scale = layer_span / scale;
 761
 762             // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
 763             base[0] += xoff;
 764
 765             // the while loops can lead to *long* pauses if base[0] comes
 766             // with a bogus value.
 767             // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
 768             // while ( base[0] < 0.0 ) { base[0] += 1.0; }
 769             if ( base[0] > -10.0 && base[0] < 10.0 ) {
 770                 base[0] -= (int)base[0];
 771             } else {
 772                 SG_LOG(SG_ASTRO, SG_DEBUG,
 773                     "Error: base = " << base[0] << "," << base[1] <<
 774                     " course = " << course << " dist = " << dist );
 775                 base[0] = 0.0;
 776             }
 777
 778             base[1] += yoff;
 779             // the while loops can lead to *long* pauses if base[0] comes
 780             // with a bogus value.
 781             // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
 782             // while ( base[1] < 0.0 ) { base[1] += 1.0; }
 783             if ( base[1] > -10.0 && base[1] < 10.0 ) {
 784                 base[1] -= (int)base[1];
 785             } else {
 786                 SG_LOG(SG_ASTRO, SG_DEBUG,
 787                         "Error: base = " << base[0] << "," << base[1] <<
 788                         " course = " << course << " dist = " << dist );
 789                 base[1] = 0.0;
 790             }
 791
 792             // cout << "base = " << base[0] << "," << base[1] << endl;
 793
 794             setTextureOffset(base);
 795             last_pos = pos;
 796         }
 797     }
 798
 799     layer3D->reposition( p, up, lon, lat, dt, layer_asl, speed, direction);
 800     return true;
 801 }
 802
 803 void SGCloudLayer::set_enable3dClouds(bool enable) {
 804
 805     if (layer3D->isDefined3D() && enable) {
 806         cloud_root->setChildValue(layer3D->getNode(), true);
 807         cloud_root->setChildValue(layer_root.get(),   false);
 808     } else {
 809         cloud_root->setChildValue(layer3D->getNode(), false);
 810         cloud_root->setChildValue(layer_root.get(),   true);
 811     }
 812 }