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