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