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 // $Id$
  22
  23 #ifdef HAVE_CONFIG_H
  24 #  include <simgear_config.h>
  25 #endif
  26
  27 #include <simgear/compiler.h>
  28
  29 #include <sstream>
  30
  31 #include <math.h>
  32
  33 #include <osg/AlphaFunc>
  34 #include <osg/BlendFunc>
  35 #include <osg/Geode>
  36 #include <osg/Geometry>
  37 #include <osg/Material>
  38 #include <osg/ShadeModel>
  39 #include <osg/TexEnv>
  40 #include <osg/Texture2D>
  41 #include <osg/TextureCubeMap>
  42 #include <osg/TexMat>
  43
  44 #include <simgear/math/sg_random.h>
  45 #include <simgear/misc/PathOptions.hxx>
  46 #include <simgear/debug/logstream.hxx>
  47 #include <simgear/scene/model/model.hxx>
  48 #include <simgear/math/polar3d.hxx>
  49
  50 #include "newcloud.hxx"
  51 #include "cloudfield.hxx"
  52 #include "cloud.hxx"
  53
  54 using namespace simgear;
  55 // #if defined(__MINGW32__)
  56 // #define isnan(x) _isnan(x)
  57 // #endif
  58
  59 // #if defined (__FreeBSD__)
  60 // #  if __FreeBSD_version < 500000
  61 //      extern "C" {
  62 //        inline int isnan(double r) { return !(r <= 0 || r >= 0); }
  63 //      }
  64 // #  endif
  65 // #endif
  66
  67 #if defined (__CYGWIN__)
  68 #include <ieeefp.h>
  69 #endif
  70
  71 static osg::ref_ptr<osg::StateSet> layer_states[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
  72 static osg::ref_ptr<osg::StateSet> layer_states2[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
  73 static osg::ref_ptr<osg::TextureCubeMap> cubeMap;
  74 static bool state_initialized = false;
  75 static bool bump_mapping = false;
  76
  77 bool SGCloudLayer::enable_bump_mapping = false;
  78
  79 // make an StateSet for a cloud layer given the named texture
  80 static osg::StateSet*
  81 SGMakeState(const SGPath &path, const char* colorTexture,
  82             const char* normalTexture)
  83 {
  84     osg::StateSet *stateSet = new osg::StateSet;
  85
  86     osg::ref_ptr<osgDB::ReaderWriter::Options> options
  87         = makeOptionsFromPath(path);
  88     stateSet->setTextureAttribute(0, SGLoadTexture2D(colorTexture,
  89                                                      options.get()));
  90     stateSet->setTextureMode(0, GL_TEXTURE_2D, osg::StateAttribute::ON);
  91
  92     osg::TexEnv* texEnv = new osg::TexEnv;
  93     texEnv->setMode(osg::TexEnv::MODULATE);
  94     stateSet->setTextureAttribute(0, texEnv);
  95
  96     osg::ShadeModel* shadeModel = new osg::ShadeModel;
  97     // FIXME: TRUE??
  98     shadeModel->setMode(osg::ShadeModel::SMOOTH);
  99     stateSet->setAttributeAndModes(shadeModel);
 100
 101     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 102     stateSet->setMode(GL_CULL_FACE, osg::StateAttribute::OFF);
 103
 104 //     osg::AlphaFunc* alphaFunc = new osg::AlphaFunc;
 105 //     alphaFunc->setFunction(osg::AlphaFunc::GREATER);
 106 //     alphaFunc->setReferenceValue(0.01);
 107 //     stateSet->setAttribute(alphaFunc);
 108 //     stateSet->setMode(GL_ALPHA_TEST, osg::StateAttribute::ON);
 109     stateSet->setMode(GL_ALPHA_TEST, osg::StateAttribute::OFF);
 110
 111     osg::BlendFunc* blendFunc = new osg::BlendFunc;
 112     blendFunc->setSource(osg::BlendFunc::SRC_ALPHA);
 113     blendFunc->setDestination(osg::BlendFunc::ONE_MINUS_SRC_ALPHA);
 114     stateSet->setAttribute(blendFunc);
 115     stateSet->setMode(GL_BLEND, osg::StateAttribute::ON);
 116
 117 //     osg::Material* material = new osg::Material;
 118 //     material->setColorMode(osg::Material::AMBIENT_AND_DIFFUSE);
 119 //     material->setEmission(osg::Material::FRONT_AND_BACK,
 120 //                           osg::Vec4(0.05, 0.05, 0.05, 0));
 121 //     material->setSpecular(osg::Material::FRONT_AND_BACK,
 122 //                           osg::Vec4(0, 0, 0, 1));
 123 //     stateSet->setAttribute(material);
 124
 125     stateSet->setMode(GL_FOG, osg::StateAttribute::OFF);
 126
 127     // OSGFIXME: invented by me ...
 128 //     stateSet->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
 129 //     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::ON);
 130
 131 //     stateSet->setMode(GL_LIGHT0, osg::StateAttribute::OFF);
 132
 133     // If the normal texture is given prepare a bumpmapping enabled state
 134 //     if (normalTexture) {
 135 //       SGPath normalPath(path);
 136 //       normalPath.append(normalTexture);
 137 //       stateSet->setTextureAttribute(2, SGLoadTexture2D(normalPath));
 138 //       stateSet->setTextureMode(2, GL_TEXTURE_2D, osg::StateAttribute::ON);
 139 //     }
 140
 141     return stateSet;
 142 }
 143
 144 // Constructor
 145 SGCloudLayer::SGCloudLayer( const string &tex_path ) :
 146     layer_root(new osg::Switch),
 147     group_top(new osg::Group),
 148     group_bottom(new osg::Group),
 149     layer_transform(new osg::MatrixTransform),
 150     cloud_alpha(1.0),
 151     texture_path(tex_path),
 152     layer_span(0.0),
 153     layer_asl(0.0),
 154     layer_thickness(0.0),
 155     layer_transition(0.0),
 156     layer_coverage(SG_CLOUD_CLEAR),
 157     scale(4000.0),
 158     speed(0.0),
 159     direction(0.0),
 160     last_lon(0.0),
 161     last_lat(0.0)
 162 {
 163   layer_root->addChild(group_bottom.get());
 164   layer_root->addChild(group_top.get());
 165   // Force the cloud layers into recursive bins of bin 4.
 166   osg::StateSet *rootSet = layer_root->getOrCreateStateSet();
 167   rootSet->setRenderBinDetails(4, "RenderBin");
 168   rootSet->setTextureAttribute(0, new osg::TexMat());
 169   base = osg::Vec2(sg_random(), sg_random());
 170
 171   group_top->addChild(layer_transform.get());
 172   group_bottom->addChild(layer_transform.get());
 173
 174   layer3D = new SGCloudField;
 175   rebuild();
 176 }
 177
 178 // Destructor
 179 SGCloudLayer::~SGCloudLayer()
 180 {
 181   delete layer3D;
 182 }
 183
 184 float
 185 SGCloudLayer::getSpan_m () const
 186 {
 187     return layer_span;
 188 }
 189
 190 void
 191 SGCloudLayer::setSpan_m (float span_m)
 192 {
 193     if (span_m != layer_span) {
 194         layer_span = span_m;
 195         rebuild();
 196     }
 197 }
 198
 199 float
 200 SGCloudLayer::getElevation_m () const
 201 {
 202     return layer_asl;
 203 }
 204
 205 void
 206 SGCloudLayer::setElevation_m (float elevation_m, bool set_span)
 207 {
 208     layer_asl = elevation_m;
 209
 210     if (set_span) {
 211         if (elevation_m > 4000)
 212             setSpan_m(  elevation_m * 10 );
 213         else
 214             setSpan_m( 40000 );
 215     }
 216 }
 217
 218 float
 219 SGCloudLayer::getThickness_m () const
 220 {
 221     return layer_thickness;
 222 }
 223
 224 void
 225 SGCloudLayer::setThickness_m (float thickness_m)
 226 {
 227     layer_thickness = thickness_m;
 228 }
 229
 230 float
 231 SGCloudLayer::getTransition_m () const
 232 {
 233     return layer_transition;
 234 }
 235
 236 void
 237 SGCloudLayer::setTransition_m (float transition_m)
 238 {
 239     layer_transition = transition_m;
 240 }
 241
 242 SGCloudLayer::Coverage
 243 SGCloudLayer::getCoverage () const
 244 {
 245     return layer_coverage;
 246 }
 247
 248 void
 249 SGCloudLayer::setCoverage (Coverage coverage)
 250 {
 251     if (coverage != layer_coverage) {
 252         layer_coverage = coverage;
 253         rebuild();
 254     }
 255 }
 256
 257 void
 258 SGCloudLayer::setTextureOffset(const osg::Vec2& offset)
 259 {
 260     osg::StateAttribute* attr = layer_root->getStateSet()
 261         ->getTextureAttribute(0, osg::StateAttribute::TEXMAT);
 262     osg::TexMat* texMat = dynamic_cast<osg::TexMat*>(attr);
 263     if (!texMat)
 264         return;
 265     texMat->setMatrix(osg::Matrix::translate(offset[0], offset[1], 0.0));
 266 }
 267
 268 // build the cloud object
 269 void
 270 SGCloudLayer::rebuild()
 271 {
 272     // Initialize states and sizes if necessary.
 273     if ( !state_initialized ) {
 274         state_initialized = true;
 275
 276         SG_LOG(SG_ASTRO, SG_INFO, "initializing cloud layers");
 277
 278         osg::Texture::Extensions* extensions;
 279         extensions = osg::Texture::getExtensions(0, true);
 280         // OSGFIXME
 281         bump_mapping = extensions->isMultiTexturingSupported() &&
 282           (2 <= extensions->numTextureUnits()) &&
 283           SGIsOpenGLExtensionSupported("GL_ARB_texture_env_combine") &&
 284           SGIsOpenGLExtensionSupported("GL_ARB_texture_env_dot3");
 285
 286         osg::TextureCubeMap::Extensions* extensions2;
 287         extensions2 = osg::TextureCubeMap::getExtensions(0, true);
 288         bump_mapping = bump_mapping && extensions2->isCubeMapSupported();
 289
 290         // This bump mapping code was inspired by the tutorial available at
 291         // http://www.paulsprojects.net/tutorials/simplebump/simplebump.html
 292         // and a NVidia white paper
 293         //  http://developer.nvidia.com/object/bumpmappingwithregistercombiners.html
 294         // The normal map textures were generated by the normal map Gimp plugin :
 295         //  http://nifelheim.dyndns.org/~cocidius/normalmap/
 296         //
 297         cubeMap = new osg::TextureCubeMap;
 298         cubeMap->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
 299         cubeMap->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
 300         cubeMap->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
 301         cubeMap->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
 302         cubeMap->setWrap(osg::Texture::WRAP_R, osg::Texture::CLAMP_TO_EDGE);
 303
 304         const int size = 32;
 305         const float half_size = 16.0f;
 306         const float offset = 0.5f;
 307         osg::Vec3 zero_normal(0.5, 0.5, 0.5);
 308
 309         osg::Image* image = new osg::Image;
 310         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 311         unsigned char *ptr = image->data(0, 0);
 312         for (int j = 0; j < size; j++ ) {
 313           for (int i = 0; i < size; i++ ) {
 314             osg::Vec3 tmp(half_size, -( j + offset - half_size ),
 315                           -( i + offset - half_size ) );
 316             tmp.normalize();
 317             tmp = tmp*0.5 - zero_normal;
 318
 319             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 320             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 321             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 322           }
 323         }
 324         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_X, image);
 325
 326         image = new osg::Image;
 327         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 328         ptr = image->data(0, 0);
 329         for (int j = 0; j < size; j++ ) {
 330           for (int i = 0; i < size; i++ ) {
 331             osg::Vec3 tmp(-half_size, -( j + offset - half_size ),
 332                           ( i + offset - half_size ) );
 333             tmp.normalize();
 334             tmp = tmp*0.5 - zero_normal;
 335
 336             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 337             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 338             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 339           }
 340         }
 341         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_X, image);
 342
 343         image = new osg::Image;
 344         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 345         ptr = image->data(0, 0);
 346         for (int j = 0; j < size; j++ ) {
 347           for (int i = 0; i < size; i++ ) {
 348             osg::Vec3 tmp(( i + offset - half_size ), half_size,
 349                           ( j + offset - half_size ) );
 350             tmp.normalize();
 351             tmp = tmp*0.5 - zero_normal;
 352
 353             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 354             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 355             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 356           }
 357         }
 358         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Y, image);
 359
 360         image = new osg::Image;
 361         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 362         ptr = image->data(0, 0);
 363         for (int j = 0; j < size; j++ ) {
 364           for (int i = 0; i < size; i++ ) {
 365             osg::Vec3 tmp(( i + offset - half_size ), -half_size,
 366                           -( j + offset - half_size ) );
 367             tmp.normalize();
 368             tmp = tmp*0.5 - zero_normal;
 369
 370             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 371             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 372             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 373           }
 374         }
 375         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Y, image);
 376
 377         image = new osg::Image;
 378         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 379         ptr = image->data(0, 0);
 380         for (int j = 0; j < size; j++ ) {
 381           for (int i = 0; i < size; i++ ) {
 382             osg::Vec3 tmp(( i + offset - half_size ),
 383                           -( j + offset - half_size ), half_size );
 384             tmp.normalize();
 385             tmp = tmp*0.5 - zero_normal;
 386
 387             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 388             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 389             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 390           }
 391         }
 392         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Z, image);
 393
 394         image = new osg::Image;
 395         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
 396         ptr = image->data(0, 0);
 397         for (int j = 0; j < size; j++ ) {
 398           for (int i = 0; i < size; i++ ) {
 399             osg::Vec3 tmp(-( i + offset - half_size ),
 400                           -( j + offset - half_size ), -half_size );
 401             tmp.normalize();
 402             tmp = tmp*0.5 - zero_normal;
 403             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
 404             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
 405             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
 406           }
 407         }
 408         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Z, image);
 409
 410         osg::StateSet* state;
 411         state = SGMakeState(texture_path, "overcast.rgb", "overcast_n.rgb");
 412         layer_states[SG_CLOUD_OVERCAST] = state;
 413         state = SGMakeState(texture_path, "overcast_top.rgb", "overcast_top_n.rgb");
 414         layer_states2[SG_CLOUD_OVERCAST] = state;
 415
 416         state = SGMakeState(texture_path, "broken.rgba", "broken_n.rgb");
 417         layer_states[SG_CLOUD_BROKEN] = state;
 418         layer_states2[SG_CLOUD_BROKEN] = state;
 419
 420         state = SGMakeState(texture_path, "scattered.rgba", "scattered_n.rgb");
 421         layer_states[SG_CLOUD_SCATTERED] = state;
 422         layer_states2[SG_CLOUD_SCATTERED] = state;
 423
 424         state = SGMakeState(texture_path, "few.rgba", "few_n.rgb");
 425         layer_states[SG_CLOUD_FEW] = state;
 426         layer_states2[SG_CLOUD_FEW] = state;
 427
 428         state = SGMakeState(texture_path, "cirrus.rgba", "cirrus_n.rgb");
 429         layer_states[SG_CLOUD_CIRRUS] = state;
 430         layer_states2[SG_CLOUD_CIRRUS] = state;
 431
 432         layer_states[SG_CLOUD_CLEAR] = 0;
 433         layer_states2[SG_CLOUD_CLEAR] = 0;
 434
 435       // OSGFIXME
 436 //              SGNewCloud::loadTextures(texture_path.str());
 437 //              layer3D->buildTestLayer();
 438     }
 439
 440     scale = 4000.0;
 441     last_lon = last_lat = -999.0f;
 442
 443     setTextureOffset(base);
 444     // build the cloud layer
 445     const float layer_scale = layer_span / scale;
 446     const float mpi = SG_PI/4;
 447
 448     // caclculate the difference between a flat-earth model and
 449     // a round earth model given the span and altutude ASL of
 450     // the cloud layer. This is the difference in altitude between
 451     // the top of the inverted bowl and the edge of the bowl.
 452     // const float alt_diff = layer_asl * 0.8;
 453     const float layer_to_core = (SG_EARTH_RAD * 1000 + layer_asl);
 454     const float layer_angle = 0.5*layer_span / layer_to_core; // The angle is half the span
 455     const float border_to_core = layer_to_core * cos(layer_angle);
 456     const float alt_diff = layer_to_core - border_to_core;
 457
 458     for (int i = 0; i < 4; i++) {
 459       if ( layer[i] != NULL ) {
 460         layer_transform->removeChild(layer[i].get()); // automatic delete
 461       }
 462
 463       vl[i] = new osg::Vec3Array;
 464       cl[i] = new osg::Vec4Array;
 465       tl[i] = new osg::Vec2Array;
 466
 467
 468       osg::Vec3 vertex(layer_span*(i-2)/2, -layer_span,
 469                        alt_diff * (sin(i*mpi) - 2));
 470       osg::Vec2 tc(layer_scale * i/4, 0.0f);
 471       osg::Vec4 color(1.0f, 1.0f, 1.0f, (i == 0) ? 0.0f : 0.15f);
 472
 473       cl[i]->push_back(color);
 474       vl[i]->push_back(vertex);
 475       tl[i]->push_back(tc);
 476
 477       for (int j = 0; j < 4; j++) {
 478         vertex = osg::Vec3(layer_span*(i-1)/2, layer_span*(j-2)/2,
 479                            alt_diff * (sin((i+1)*mpi) + sin(j*mpi) - 2));
 480         tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale * j/4);
 481         color = osg::Vec4(1.0f, 1.0f, 1.0f,
 482                           ( (j == 0) || (i == 3)) ?
 483                           ( (j == 0) && (i == 3)) ? 0.0f : 0.15f : 1.0f );
 484
 485         cl[i]->push_back(color);
 486         vl[i]->push_back(vertex);
 487         tl[i]->push_back(tc);
 488
 489         vertex = osg::Vec3(layer_span*(i-2)/2, layer_span*(j-1)/2,
 490                            alt_diff * (sin(i*mpi) + sin((j+1)*mpi) - 2) );
 491         tc = osg::Vec2(layer_scale * i/4, layer_scale * (j+1)/4 );
 492         color = osg::Vec4(1.0f, 1.0f, 1.0f,
 493                           ((j == 3) || (i == 0)) ?
 494                           ((j == 3) && (i == 0)) ? 0.0f : 0.15f : 1.0f );
 495         cl[i]->push_back(color);
 496         vl[i]->push_back(vertex);
 497         tl[i]->push_back(tc);
 498       }
 499
 500       vertex = osg::Vec3(layer_span*(i-1)/2, layer_span,
 501                          alt_diff * (sin((i+1)*mpi) - 2));
 502
 503       tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale);
 504
 505       color = osg::Vec4(1.0f, 1.0f, 1.0f, (i == 3) ? 0.0f : 0.15f );
 506
 507       cl[i]->push_back( color );
 508       vl[i]->push_back( vertex );
 509       tl[i]->push_back( tc );
 510
 511       osg::Geometry* geometry = new osg::Geometry;
 512       geometry->setUseDisplayList(false);
 513       geometry->setVertexArray(vl[i].get());
 514       geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 515       geometry->setColorArray(cl[i].get());
 516       geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 517       geometry->setTexCoordArray(0, tl[i].get());
 518       geometry->addPrimitiveSet(new osg::DrawArrays(GL_TRIANGLE_STRIP, 0, vl[i]->size()));
 519       layer[i] = new osg::Geode;
 520
 521       std::stringstream sstr;
 522       sstr << "Cloud Layer (" << i << ")";
 523       geometry->setName(sstr.str());
 524       layer[i]->setName(sstr.str());
 525       layer[i]->addDrawable(geometry);
 526       layer_transform->addChild(layer[i].get());
 527     }
 528
 529     //OSGFIXME: true
 530     if ( layer_states[layer_coverage].valid() ) {
 531       osg::CopyOp copyOp(osg::CopyOp::DEEP_COPY_ALL
 532                          & ~osg::CopyOp::DEEP_COPY_TEXTURES);
 533       // render bin will be set in reposition
 534       osg::StateSet* stateSet = static_cast<osg::StateSet*>(layer_states2[layer_coverage]->clone(copyOp));
 535       stateSet->setDataVariance(osg::Object::DYNAMIC);
 536       group_top->setStateSet(stateSet);
 537       stateSet = static_cast<osg::StateSet*>(layer_states2[layer_coverage]->clone(copyOp));
 538       stateSet->setDataVariance(osg::Object::DYNAMIC);
 539       group_bottom->setStateSet(stateSet);
 540     }
 541 }
 542
 543 #if 0
 544             sgMat4 modelview,
 545                    tmp,
 546                    transform;
 547             ssgGetModelviewMatrix( modelview );
 548             layer_transform->getTransform( transform );
 549
 550             sgTransposeNegateMat4( tmp, transform );
 551
 552             sgPostMultMat4( transform, modelview );
 553             ssgLoadModelviewMatrix( transform );
 554
 555             sgVec3 lightVec;
 556             ssgGetLight( 0 )->getPosition( lightVec );
 557             sgNegateVec3( lightVec );
 558             sgXformVec3( lightVec, tmp );
 559
 560             for ( int i = 0; i < 25; i++ ) {
 561                 CloudVertex &v = vertices[ i ];
 562                 sgSetVec3( v.tangentSpLight,
 563                            sgScalarProductVec3( v.sTangent, lightVec ),
 564                            sgScalarProductVec3( v.tTangent, lightVec ),
 565                            sgScalarProductVec3( v.normal, lightVec ) );
 566             }
 567
 568             ssgTexture *decal = color_map[ layer_coverage ][ top ? 1 : 0 ];
 569             if ( top && decal == 0 ) {
 570                 decal = color_map[ layer_coverage ][ 0 ];
 571             }
 572             ssgTexture *normal = normal_map[ layer_coverage ][ top ? 1 : 0 ];
 573             if ( top && normal == 0 ) {
 574                 normal = normal_map[ layer_coverage ][ 0 ];
 575             }
 576
 577             glDisable( GL_LIGHTING );
 578             glDisable( GL_CULL_FACE );
 579 //            glDisable( GL_ALPHA_TEST );
 580             if ( layer_coverage == SG_CLOUD_FEW ) {
 581                 glEnable( GL_ALPHA_TEST );
 582                 glAlphaFunc ( GL_GREATER, 0.01 );
 583             }
 584             glEnable( GL_BLEND );
 585             glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
 586
 587             glShadeModel( GL_SMOOTH );
 588             glEnable( GL_COLOR_MATERIAL );
 589             sgVec4 color;
 590             float emis = 0.05;
 591             if ( 1 ) {
 592                 ssgGetLight( 0 )->getColour( GL_DIFFUSE, color );
 593                 emis = ( color[0]+color[1]+color[2] ) / 3.0;
 594                 if ( emis < 0.05 )
 595                     emis = 0.05;
 596             }
 597             sgSetVec4( color, emis, emis, emis, 0.0 );
 598             glMaterialfv( GL_FRONT_AND_BACK, GL_EMISSION, color );
 599             sgSetVec4( color, 1.0f, 1.0f, 1.0f, 0.0 );
 600             glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT, color );
 601             sgSetVec4( color, 1.0, 1.0, 1.0, 0.0 );
 602             glMaterialfv( GL_FRONT_AND_BACK, GL_DIFFUSE, color );
 603             sgSetVec4( color, 0.0, 0.0, 0.0, 0.0 );
 604             glMaterialfv( GL_FRONT_AND_BACK, GL_SPECULAR, color );
 605
 606             glColor4f( 1.0f, 1.0f, 1.0f, 1.0f );
 607
 608             glActiveTexturePtr( GL_TEXTURE0_ARB );
 609             glBindTexture( GL_TEXTURE_2D, normal->getHandle() );
 610             glEnable( GL_TEXTURE_2D );
 611
 612             //Bind normalisation cube map to texture unit 1
 613             glActiveTexturePtr( GL_TEXTURE1_ARB );
 614             glBindTexture( GL_TEXTURE_CUBE_MAP_ARB, normalization_cube_map );
 615             glEnable( GL_TEXTURE_CUBE_MAP_ARB );
 616             glActiveTexturePtr( GL_TEXTURE0_ARB );
 617
 618             //Set vertex arrays for cloud
 619             glVertexPointer( 3, GL_FLOAT, sizeof(CloudVertex), &vertices[0].position );
 620             glEnableClientState( GL_VERTEX_ARRAY );
 621 /*
 622             if ( nb_texture_unit >= 3 ) {
 623                 glColorPointer( 4, GL_FLOAT, sizeof(CloudVertex), &vertices[0].color );
 624                 glEnableClientState( GL_COLOR_ARRAY );
 625             }
 626 */
 627             //Send texture coords for normal map to unit 0
 628             glTexCoordPointer( 2, GL_FLOAT, sizeof(CloudVertex), &vertices[0].texCoord );
 629             glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 630
 631             //Send tangent space light vectors for normalisation to unit 1
 632             glClientActiveTexturePtr( GL_TEXTURE1_ARB );
 633             glTexCoordPointer( 3, GL_FLOAT, sizeof(CloudVertex), &vertices[0].tangentSpLight );
 634             glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 635
 636             //Set up texture environment to do (tex0 dot tex1)*color
 637             glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB );
 638             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE );
 639             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_REPLACE );
 640             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_TEXTURE );
 641             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_REPLACE );
 642
 643 // use TexEnvCombine to add the highlights to the original lighting
 644 osg::TexEnvCombine *te = new osg::TexEnvCombine;
 645 te->setSource0_RGB(osg::TexEnvCombine::TEXTURE);
 646 te->setCombine_RGB(osg::TexEnvCombine::REPLACE);
 647 te->setSource0_Alpha(osg::TexEnvCombine::TEXTURE);
 648 te->setCombine_Alpha(osg::TexEnvCombine::REPLACE);
 649 ss->setTextureAttributeAndModes(0, te, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
 650
 651
 652             glActiveTexturePtr( GL_TEXTURE1_ARB );
 653
 654             glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB );
 655             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE );
 656             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_DOT3_RGB_ARB );
 657             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PREVIOUS_ARB );
 658             glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_PREVIOUS_ARB );
 659             glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_REPLACE );
 660
 661 osg::TexEnvCombine *te = new osg::TexEnvCombine;
 662 te->setSource0_RGB(osg::TexEnvCombine::TEXTURE);
 663 te->setCombine_RGB(osg::TexEnvCombine::DOT3_RGB);
 664 te->setSource1_RGB(osg::TexEnvCombine::PREVIOUS);
 665 te->setSource0_Alpha(osg::TexEnvCombine::PREVIOUS);
 666 te->setCombine_Alpha(osg::TexEnvCombine::REPLACE);
 667 ss->setTextureAttributeAndModes(0, te, osg::StateAttribute::OVERRIDE | osg::StateAttribute::ON);
 668
 669
 670             if ( nb_texture_unit >= 3 ) {
 671                 glActiveTexturePtr( GL_TEXTURE2_ARB );
 672                 glBindTexture( GL_TEXTURE_2D, decal->getHandle() );
 673
 674                 glClientActiveTexturePtr( GL_TEXTURE2_ARB );
 675                 glTexCoordPointer( 2, GL_FLOAT, sizeof(CloudVertex), &vertices[0].texCoord );
 676                 glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 677
 678                 glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB );
 679                 glTexEnvi( GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_ADD );
 680                 glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE );
 681                 glTexEnvi( GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PREVIOUS_ARB );
 682
 683                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 684                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 685
 686                 //Draw cloud layer
 687                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[0] );
 688                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[10] );
 689                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[20] );
 690                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[30] );
 691
 692                 glDisable( GL_TEXTURE_2D );
 693                 glActiveTexturePtr( GL_TEXTURE1_ARB );
 694                 glDisable( GL_TEXTURE_CUBE_MAP_ARB );
 695                 glActiveTexturePtr( GL_TEXTURE2_ARB );
 696                 glDisable( GL_TEXTURE_2D );
 697                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 698
 699                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 700                 glClientActiveTexturePtr( GL_TEXTURE1_ARB );
 701                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 702                 glClientActiveTexturePtr( GL_TEXTURE2_ARB );
 703                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 704                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 705
 706                 glDisableClientState( GL_COLOR_ARRAY );
 707                 glEnable( GL_LIGHTING );
 708
 709                 glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
 710
 711             } else {
 712                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 713                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 714
 715                 //Draw cloud layer
 716                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[0] );
 717                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[10] );
 718                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[20] );
 719                 glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[30] );
 720
 721                 //Disable textures
 722                 glDisable( GL_TEXTURE_2D );
 723
 724                 glActiveTexturePtr( GL_TEXTURE1_ARB );
 725                 glDisable( GL_TEXTURE_CUBE_MAP_ARB );
 726                 glActiveTexturePtr( GL_TEXTURE0_ARB );
 727
 728                 //disable vertex arrays
 729                 glDisableClientState( GL_VERTEX_ARRAY );
 730
 731                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 732                 glClientActiveTexturePtr( GL_TEXTURE1_ARB );
 733                 glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 734                 glClientActiveTexturePtr( GL_TEXTURE0_ARB );
 735
 736                 //Return to standard modulate texenv
 737                 glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
 738
 739                 if ( layer_coverage == SG_CLOUD_OVERCAST ) {
 740                     glDepthFunc(GL_LEQUAL);
 741
 742                     glEnable( GL_LIGHTING );
 743                     sgVec4 color;
 744                     ssgGetLight( 0 )->getColour( GL_DIFFUSE, color );
 745                     float average = ( color[0] + color[1] + color[2] ) / 3.0f;
 746                     average = 0.15 + average/10;
 747                     sgVec4 averageColor;
 748                     sgSetVec4( averageColor, average, average, average, 1.0f );
 749                     ssgGetLight( 0 )->setColour( GL_DIFFUSE, averageColor );
 750
 751                     glBlendColorPtr( average, average, average, 1.0f );
 752                     glBlendFunc( GL_ONE_MINUS_CONSTANT_COLOR, GL_CONSTANT_COLOR );
 753
 754                     //Perform a second pass to color the torus
 755                     //Bind decal texture
 756                     glBindTexture( GL_TEXTURE_2D, decal->getHandle() );
 757                     glEnable(GL_TEXTURE_2D);
 758
 759                     //Set vertex arrays for torus
 760                     glVertexPointer( 3, GL_FLOAT, sizeof(CloudVertex), &vertices[0].position );
 761                     glEnableClientState( GL_VERTEX_ARRAY );
 762
 763                     //glColorPointer( 4, GL_FLOAT, sizeof(CloudVertex), &vertices[0].color );
 764                     //glEnableClientState( GL_COLOR_ARRAY );
 765
 766                     glNormalPointer( GL_FLOAT, sizeof(CloudVertex), &vertices[0].normal );
 767                     glEnableClientState( GL_NORMAL_ARRAY );
 768
 769                     glTexCoordPointer( 2, GL_FLOAT, sizeof(CloudVertex), &vertices[0].texCoord );
 770                     glEnableClientState( GL_TEXTURE_COORD_ARRAY );
 771
 772                     //Draw cloud layer
 773                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[0] );
 774                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[10] );
 775                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[20] );
 776                     glDrawElements( GL_TRIANGLE_STRIP, 10, GL_UNSIGNED_INT, &indices[30] );
 777
 778                     ssgGetLight( 0 )->setColour( GL_DIFFUSE, color );
 779
 780                     glDisableClientState( GL_TEXTURE_COORD_ARRAY );
 781                 }
 782             }
 783             //Disable texture
 784             glDisable( GL_TEXTURE_2D );
 785
 786             glDisableClientState( GL_VERTEX_ARRAY );
 787             glDisableClientState( GL_NORMAL_ARRAY );
 788
 789             glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
 790             glEnable( GL_CULL_FACE );
 791             glDepthFunc(GL_LESS);
 792
 793             ssgLoadModelviewMatrix( modelview );
 794 #endif
 795
 796 // repaint the cloud layer colors
 797 bool SGCloudLayer::repaint( const SGVec3f& fog_color ) {
 798   for ( int i = 0; i < 4; i++ ) {
 799     osg::Vec4 color(fog_color.osg(), 1);
 800     color[3] = (i == 0) ? 0.0f : cloud_alpha * 0.15f;
 801     (*cl[i])[0] = color;
 802
 803     for ( int j = 0; j < 4; ++j ) {
 804       color[3] =
 805         ((j == 0) || (i == 3)) ?
 806         ((j == 0) && (i == 3)) ? 0.0f : cloud_alpha * 0.15f : cloud_alpha;
 807       (*cl[i])[(2*j) + 1] = color;
 808
 809       color[3] =
 810         ((j == 3) || (i == 0)) ?
 811         ((j == 3) && (i == 0)) ? 0.0f : cloud_alpha * 0.15f : cloud_alpha;
 812       (*cl[i])[(2*j) + 2] = color;
 813     }
 814
 815     color[3] = (i == 3) ? 0.0f : cloud_alpha * 0.15f;
 816     (*cl[i])[9] = color;
 817
 818     cl[i]->dirty();
 819   }
 820
 821   return true;
 822 }
 823
 824 // reposition the cloud layer at the specified origin and orientation
 825 // lon specifies a rotation about the Z axis
 826 // lat specifies a rotation about the new Y axis
 827 // spin specifies a rotation about the new Z axis (and orients the
 828 // sunrise/set effects
 829 bool SGCloudLayer::reposition( const SGVec3f& p, const SGVec3f& up, double lon, double lat,
 830                                double alt, double dt )
 831 {
 832     // combine p and asl (meters) to get translation offset
 833     osg::Vec3 asl_offset(up.osg());
 834     asl_offset.normalize();
 835     if ( alt <= layer_asl ) {
 836         asl_offset *= layer_asl;
 837     } else {
 838         asl_offset *= layer_asl + layer_thickness;
 839     }
 840
 841     // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 842     //      << "," << asl_offset[2] << endl;
 843     asl_offset += p.osg();
 844     // cout << "  asl_offset = " << asl_offset[0] << "," << asl_offset[1]
 845     //      << "," << asl_offset[2] << endl;
 846
 847     osg::Matrix T, LON, LAT;
 848     // Translate to zero elevation
 849     // Point3D zero_elev = current_view.get_cur_zero_elev();
 850     T.makeTranslate( asl_offset );
 851
 852     // printf("  Translated to %.2f %.2f %.2f\n",
 853     //        zero_elev.x, zero_elev.y, zero_elev.z );
 854
 855     // Rotate to proper orientation
 856     // printf("  lon = %.2f  lat = %.2f\n",
 857     //        lon * SGD_RADIANS_TO_DEGREES,
 858     //        lat * SGD_RADIANS_TO_DEGREES);
 859     LON.makeRotate(lon, osg::Vec3(0, 0, 1));
 860
 861     // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
 862     //             0.0, 1.0, 0.0 );
 863     LAT.makeRotate(90.0 * SGD_DEGREES_TO_RADIANS - lat, osg::Vec3(0, 1, 0));
 864
 865     layer_transform->setMatrix( LAT*LON*T );
 866     // The layers need to be drawn in order because they are
 867     // translucent, but OSG transparency sorting doesn't work because
 868     // the cloud polys are huge. However, the ordering is simple: the
 869     // bottom polys should be drawn from high altitude to low, and the
 870     // top polygons from low to high. The altitude can be used
 871     // directly to order the polygons!
 872     layer_root->getChild(0)->getStateSet()->setRenderBinDetails(-(int)layer_asl,
 873                                                                 "RenderBin");
 874     layer_root->getChild(1)->getStateSet()->setRenderBinDetails((int)layer_asl,
 875                                                                 "RenderBin");
 876     if ( alt <= layer_asl ) {
 877       layer_root->setSingleChildOn(0);
 878     } else if ( alt >= layer_asl + layer_thickness ) {
 879       layer_root->setSingleChildOn(1);
 880     } else {
 881       layer_root->setAllChildrenOff();
 882     }
 883
 884
 885     // now calculate update texture coordinates
 886     if ( last_lon < -900 ) {
 887         last_lon = lon;
 888         last_lat = lat;
 889     }
 890
 891     double sp_dist = speed*dt;
 892
 893     if ( lon != last_lon || lat != last_lat || sp_dist != 0 ) {
 894         Point3D start( last_lon, last_lat, 0.0 );
 895         Point3D dest( lon, lat, 0.0 );
 896         double course = 0.0, dist = 0.0;
 897
 898         calc_gc_course_dist( dest, start, &course, &dist );
 899         // cout << "course = " << course << ", dist = " << dist << endl;
 900
 901         // if start and dest are too close together,
 902         // calc_gc_course_dist() can return a course of "nan".  If
 903         // this happens, lets just use the last known good course.
 904         // This is a hack, and it would probably be better to make
 905         // calc_gc_course_dist() more robust.
 906         if ( isnan(course) ) {
 907             course = last_course;
 908         } else {
 909             last_course = course;
 910         }
 911
 912         // calculate cloud movement due to external forces
 913         double ax = 0.0, ay = 0.0, bx = 0.0, by = 0.0;
 914
 915         if (dist > 0.0) {
 916             ax = cos(course) * dist;
 917             ay = sin(course) * dist;
 918         }
 919
 920         if (sp_dist > 0) {
 921             bx = cos((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 922             by = sin((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
 923         }
 924
 925
 926         double xoff = (ax + bx) / (2 * scale);
 927         double yoff = (ay + by) / (2 * scale);
 928
 929         const float layer_scale = layer_span / scale;
 930
 931         // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
 932         base[0] += xoff;
 933
 934         // the while loops can lead to *long* pauses if base[0] comes
 935         // with a bogus value.
 936         // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
 937         // while ( base[0] < 0.0 ) { base[0] += 1.0; }
 938         if ( base[0] > -10.0 && base[0] < 10.0 ) {
 939             base[0] -= (int)base[0];
 940         } else {
 941             SG_LOG(SG_ASTRO, SG_DEBUG,
 942                 "Error: base = " << base[0] << "," << base[1] <<
 943                 " course = " << course << " dist = " << dist );
 944             base[0] = 0.0;
 945         }
 946
 947         base[1] += yoff;
 948         // the while loops can lead to *long* pauses if base[0] comes
 949         // with a bogus value.
 950         // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
 951         // while ( base[1] < 0.0 ) { base[1] += 1.0; }
 952         if ( base[1] > -10.0 && base[1] < 10.0 ) {
 953             base[1] -= (int)base[1];
 954         } else {
 955             SG_LOG(SG_ASTRO, SG_DEBUG,
 956                     "Error: base = " << base[0] << "," << base[1] <<
 957                     " course = " << course << " dist = " << dist );
 958             base[1] = 0.0;
 959         }
 960
 961         // cout << "base = " << base[0] << "," << base[1] << endl;
 962
 963         setTextureOffset(base);
 964         last_lon = lon;
 965         last_lat = lat;
 966     }
 967
 968 //      layer3D->reposition( p, up, lon, lat, alt, dt, direction, speed);
 969     return true;
 970 }