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