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