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