SimGear: cloud.cxx Source File

00001 // cloud.cxx -- model a single cloud layer
00002 //
00003 // Written by Curtis Olson, started June 2000.
00004 //
00005 // Copyright (C) 2000  Curtis L. Olson  - http://www.flightgear.org/~curt
00006 //
00007 // This library is free software; you can redistribute it and/or
00008 // modify it under the terms of the GNU Library General Public
00009 // License as published by the Free Software Foundation; either
00010 // version 2 of the License, or (at your option) any later version.
00011 //
00012 // This library is distributed in the hope that it will be useful, but
00013 // WITHOUT ANY WARRANTY; without even the implied warranty of
00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015 // General Public License for more details.
00016 //
00017 // You should have received a copy of the GNU General Public License
00018 // along with this program; if not, write to the Free Software
00019 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
00020 //
00021 // $Id: cloud_8cxx_source.html,v 1.3 2010/02/23 22:10:12 curt Exp $
00022 
00023 #ifdef HAVE_CONFIG_H
00024 #  include <simgear_config.h>
00025 #endif
00026 
00027 #include <simgear/compiler.h>
00028 
00029 #include <sstream>
00030 
00031 #include <math.h>
00032 
00033 #include <simgear/structure/OSGVersion.hxx>
00034 #include <osg/AlphaFunc>
00035 #include <osg/BlendFunc>
00036 #include <osg/CullFace>
00037 #include <osg/Geode>
00038 #include <osg/Geometry>
00039 #include <osg/Material>
00040 #include <osg/ShadeModel>
00041 #include <osg/TexEnv>
00042 #include <osg/TexEnvCombine>
00043 #include <osg/Texture2D>
00044 #include <osg/TextureCubeMap>
00045 #include <osg/TexMat>
00046 #include <osg/Fog>
00047 #if SG_OSG_MIN_VERSION_REQUIRED(2,9,5)
00048 #include <osgDB/Options>
00049 #endif
00050 
00051 #include <simgear/math/sg_random.h>
00052 #include <simgear/misc/PathOptions.hxx>
00053 #include <simgear/debug/logstream.hxx>
00054 #include <simgear/scene/model/model.hxx>
00055 #include <simgear/scene/util/RenderConstants.hxx>
00056 #include <simgear/scene/util/StateAttributeFactory.hxx>
00057 #include <simgear/math/polar3d.hxx>
00058 
00059 #include "newcloud.hxx"
00060 #include "cloudfield.hxx"
00061 #include "cloud.hxx"
00062 
00063 using namespace simgear;
00064 using namespace osg;
00065 
00066 #if defined(__MINGW32__)
00067 #define isnan(x) _isnan(x)
00068 #endif
00069 
00070 // #if defined (__FreeBSD__)
00071 // #  if __FreeBSD_version < 500000
00072 //      extern "C" {
00073 //        inline int isnan(double r) { return !(r <= 0 || r >= 0); }
00074 //      }
00075 // #  endif
00076 // #endif
00077 
00078 static osg::ref_ptr<osg::StateSet> layer_states[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
00079 static osg::ref_ptr<osg::StateSet> layer_states2[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
00080 static osg::ref_ptr<osg::TextureCubeMap> cubeMap;
00081 static bool state_initialized = false;
00082 static bool bump_mapping = false;
00083 
00084 bool SGCloudLayer::enable_bump_mapping = false;
00085 
00086 // make an StateSet for a cloud layer given the named texture
00087 static osg::StateSet*
00088 SGMakeState(const SGPath &path, const char* colorTexture,
00089             const char* normalTexture)
00090 {
00091     osg::StateSet *stateSet = new osg::StateSet;
00092 
00093     osg::ref_ptr<osgDB::ReaderWriter::Options> options
00094         = makeOptionsFromPath(path);
00095     stateSet->setTextureAttribute(0, SGLoadTexture2D(colorTexture,
00096                                                      options.get()));
00097     stateSet->setTextureMode(0, GL_TEXTURE_2D, osg::StateAttribute::ON);
00098     StateAttributeFactory* attribFactory = StateAttributeFactory::instance();
00099     stateSet->setAttributeAndModes(attribFactory->getSmoothShadeModel());
00100     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
00101     stateSet->setAttributeAndModes(attribFactory->getStandardAlphaFunc());
00102     stateSet->setAttributeAndModes(attribFactory->getStandardBlendFunc());
00103 
00104 //     osg::Material* material = new osg::Material;
00105 //     material->setColorMode(osg::Material::AMBIENT_AND_DIFFUSE);
00106 //     material->setEmission(osg::Material::FRONT_AND_BACK,
00107 //                           osg::Vec4(0.05, 0.05, 0.05, 0));
00108 //     material->setSpecular(osg::Material::FRONT_AND_BACK,
00109 //                           osg::Vec4(0, 0, 0, 1));
00110 //     stateSet->setAttribute(material);
00111 
00112     stateSet->setMode(GL_FOG, osg::StateAttribute::OFF);
00113 
00114     // OSGFIXME: invented by me ...
00115 //     stateSet->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
00116 //     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::ON);
00117 
00118 //     stateSet->setMode(GL_LIGHT0, osg::StateAttribute::OFF);
00119 
00120     // If the normal texture is given prepare a bumpmapping enabled state
00121 //     if (normalTexture) {
00122 //       SGPath normalPath(path);
00123 //       normalPath.append(normalTexture);
00124 //       stateSet->setTextureAttribute(2, SGLoadTexture2D(normalPath));
00125 //       stateSet->setTextureMode(2, GL_TEXTURE_2D, osg::StateAttribute::ON);
00126 //     }
00127 
00128     return stateSet;
00129 }
00130 
00131 // Constructor
00132 SGCloudLayer::SGCloudLayer( const string &tex_path ) :
00133     cloud_root(new osg::Switch),
00134     layer_root(new osg::Switch),
00135     group_top(new osg::Group),
00136     group_bottom(new osg::Group),
00137     layer_transform(new osg::MatrixTransform),
00138     cloud_alpha(1.0),
00139     texture_path(tex_path),
00140     layer_span(0.0),
00141     layer_asl(0.0),
00142     layer_thickness(0.0),
00143     layer_transition(0.0),
00144     layer_coverage(SG_CLOUD_CLEAR),
00145     scale(4000.0),
00146     speed(0.0),
00147     direction(0.0),
00148     last_lon(0.0),
00149     last_lat(0.0)
00150 {
00151     // XXX
00152     // Render bottoms before the rest of transparent objects (rendered
00153     // in bin 10), tops after. The negative numbers on the bottoms
00154     // RenderBins and the positive numbers on the tops enforce this
00155     // order.
00156   cloud_root->addChild(layer_root.get(), true);
00157   layer_root->addChild(group_bottom.get());
00158   layer_root->addChild(group_top.get());
00159   osg::StateSet *rootSet = layer_root->getOrCreateStateSet();
00160   rootSet->setRenderBinDetails(CLOUDS_BIN, "DepthSortedBin");
00161   rootSet->setTextureAttribute(0, new osg::TexMat);
00162   rootSet->setMode(GL_CULL_FACE, osg::StateAttribute::ON);
00163   // Combiner for fog color and cloud alpha
00164   osg::TexEnvCombine* combine0 = new osg::TexEnvCombine;
00165   osg::TexEnvCombine* combine1 = new osg::TexEnvCombine;
00166   combine0->setCombine_RGB(osg::TexEnvCombine::MODULATE);
00167   combine0->setSource0_RGB(osg::TexEnvCombine::PREVIOUS);
00168   combine0->setOperand0_RGB(osg::TexEnvCombine::SRC_COLOR);
00169   combine0->setSource1_RGB(osg::TexEnvCombine::TEXTURE0);
00170   combine0->setOperand1_RGB(osg::TexEnvCombine::SRC_COLOR);
00171   combine0->setCombine_Alpha(osg::TexEnvCombine::MODULATE);
00172   combine0->setSource0_Alpha(osg::TexEnvCombine::PREVIOUS);
00173   combine0->setOperand0_Alpha(osg::TexEnvCombine::SRC_ALPHA);
00174   combine0->setSource1_Alpha(osg::TexEnvCombine::TEXTURE0);
00175   combine0->setOperand1_Alpha(osg::TexEnvCombine::SRC_ALPHA);
00176 
00177   combine1->setCombine_RGB(osg::TexEnvCombine::MODULATE);
00178   combine1->setSource0_RGB(osg::TexEnvCombine::PREVIOUS);
00179   combine1->setOperand0_RGB(osg::TexEnvCombine::SRC_COLOR);
00180   combine1->setSource1_RGB(osg::TexEnvCombine::CONSTANT);
00181   combine1->setOperand1_RGB(osg::TexEnvCombine::SRC_COLOR);
00182   combine1->setCombine_Alpha(osg::TexEnvCombine::MODULATE);
00183   combine1->setSource0_Alpha(osg::TexEnvCombine::PREVIOUS);
00184   combine1->setOperand0_Alpha(osg::TexEnvCombine::SRC_ALPHA);
00185   combine1->setSource1_Alpha(osg::TexEnvCombine::CONSTANT);
00186   combine1->setOperand1_Alpha(osg::TexEnvCombine::SRC_ALPHA);
00187   combine1->setDataVariance(osg::Object::DYNAMIC);
00188   rootSet->setTextureAttributeAndModes(0, combine0);
00189   rootSet->setTextureAttributeAndModes(1, combine1);
00190   rootSet->setTextureMode(1, GL_TEXTURE_2D, osg::StateAttribute::ON);
00191   rootSet->setTextureAttributeAndModes(1, StateAttributeFactory::instance()
00192                                        ->getWhiteTexture(),
00193                                        osg::StateAttribute::ON);
00194   rootSet->setDataVariance(osg::Object::DYNAMIC);
00195 
00196   base = osg::Vec2(sg_random(), sg_random());
00197   group_top->addChild(layer_transform.get());
00198   group_bottom->addChild(layer_transform.get());
00199 
00200   layer3D = new SGCloudField();
00201   cloud_root->addChild(layer3D->getNode(), false);
00202 
00203   rebuild();
00204 }
00205 
00206 // Destructor
00207 SGCloudLayer::~SGCloudLayer()
00208 {
00209   delete layer3D;
00210 }
00211 
00212 float
00213 SGCloudLayer::getSpan_m () const
00214 {
00215     return layer_span;
00216 }
00217 
00218 void
00219 SGCloudLayer::setSpan_m (float span_m)
00220 {
00221     if (span_m != layer_span) {
00222         layer_span = span_m;
00223         rebuild();
00224     }
00225 }
00226 
00227 float
00228 SGCloudLayer::getElevation_m () const
00229 {
00230     return layer_asl;
00231 }
00232 
00233 void
00234 SGCloudLayer::setElevation_m (float elevation_m, bool set_span)
00235 {
00236     layer_asl = elevation_m;
00237 
00238     if (set_span) {
00239         if (elevation_m > 4000)
00240             setSpan_m(  elevation_m * 10 );
00241         else
00242             setSpan_m( 40000 );
00243     }
00244 }
00245 
00246 float
00247 SGCloudLayer::getThickness_m () const
00248 {
00249     return layer_thickness;
00250 }
00251 
00252 void
00253 SGCloudLayer::setThickness_m (float thickness_m)
00254 {
00255     layer_thickness = thickness_m;
00256 }
00257 
00258 float
00259 SGCloudLayer::getTransition_m () const
00260 {
00261     return layer_transition;
00262 }
00263 
00264 void
00265 SGCloudLayer::setTransition_m (float transition_m)
00266 {
00267     layer_transition = transition_m;
00268 }
00269 
00270 SGCloudLayer::Coverage
00271 SGCloudLayer::getCoverage () const
00272 {
00273     return layer_coverage;
00274 }
00275 
00276 void
00277 SGCloudLayer::setCoverage (Coverage coverage)
00278 {
00279     if (coverage != layer_coverage) {
00280         layer_coverage = coverage;
00281         rebuild();
00282         
00283         double coverage_norm = 0.0;
00284         if( coverage ==  SG_CLOUD_FEW)
00285             coverage_norm = 2.0/8.0;    // <1-2
00286         else if( coverage == SG_CLOUD_SCATTERED )
00287             coverage_norm = 4.0/8.0;    // 3-4
00288         else if( coverage == SG_CLOUD_BROKEN )
00289             coverage_norm = 6.0/8.0;    // 5-7
00290         else if( coverage == SG_CLOUD_OVERCAST )
00291             coverage_norm = 8.0/8.0;    // 8
00292         
00293         layer3D->setCoverage(coverage_norm);
00294         layer3D->applyCoverage();
00295     }
00296 }
00297 
00298 void
00299 SGCloudLayer::setTextureOffset(const osg::Vec2& offset)
00300 {
00301     osg::StateAttribute* attr = layer_root->getStateSet()
00302         ->getTextureAttribute(0, osg::StateAttribute::TEXMAT);
00303     osg::TexMat* texMat = dynamic_cast<osg::TexMat*>(attr);
00304     if (!texMat)
00305         return;
00306     texMat->setMatrix(osg::Matrix::translate(offset[0], offset[1], 0.0));
00307 }
00308 
00309 // colors for debugging the cloud layers
00310 #ifdef CLOUD_DEBUG
00311 Vec3 cloudColors[] = {Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 0.0f, 0.0f),
00312                       Vec3(0.0f, 1.0f, 0.0f), Vec3(0.0f, 0.0f, 1.0f)};
00313 #else
00314 Vec3 cloudColors[] = {Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 1.0f, 1.0f),
00315                       Vec3(1.0f, 1.0f, 1.0f), Vec3(1.0f, 1.0f, 1.0f)};
00316 #endif
00317 
00318 // build the cloud object
00319 void
00320 SGCloudLayer::rebuild()
00321 {
00322     // Initialize states and sizes if necessary.
00323     if ( !state_initialized ) { 
00324         state_initialized = true;
00325 
00326         SG_LOG(SG_ASTRO, SG_INFO, "initializing cloud layers");
00327 
00328         osg::Texture::Extensions* extensions;
00329         extensions = osg::Texture::getExtensions(0, true);
00330         // OSGFIXME
00331         bump_mapping = extensions->isMultiTexturingSupported() &&
00332           (2 <= extensions->numTextureUnits()) &&
00333           SGIsOpenGLExtensionSupported("GL_ARB_texture_env_combine") &&
00334           SGIsOpenGLExtensionSupported("GL_ARB_texture_env_dot3");
00335 
00336         osg::TextureCubeMap::Extensions* extensions2;
00337         extensions2 = osg::TextureCubeMap::getExtensions(0, true);
00338         bump_mapping = bump_mapping && extensions2->isCubeMapSupported();
00339 
00340         // This bump mapping code was inspired by the tutorial available at 
00341         // http://www.paulsprojects.net/tutorials/simplebump/simplebump.html
00342         // and a NVidia white paper 
00343         //  http://developer.nvidia.com/object/bumpmappingwithregistercombiners.html
00344         // The normal map textures were generated by the normal map Gimp plugin :
00345         //  http://nifelheim.dyndns.org/~cocidius/normalmap/
00346         //
00347         cubeMap = new osg::TextureCubeMap;
00348         cubeMap->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR);
00349         cubeMap->setFilter(osg::Texture::MAG_FILTER, osg::Texture::LINEAR);
00350         cubeMap->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP_TO_EDGE);
00351         cubeMap->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP_TO_EDGE);
00352         cubeMap->setWrap(osg::Texture::WRAP_R, osg::Texture::CLAMP_TO_EDGE);
00353 
00354         const int size = 32;
00355         const float half_size = 16.0f;
00356         const float offset = 0.5f;
00357         osg::Vec3 zero_normal(0.5, 0.5, 0.5);
00358 
00359         osg::Image* image = new osg::Image;
00360         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
00361         unsigned char *ptr = image->data(0, 0);
00362         for (int j = 0; j < size; j++ ) {
00363           for (int i = 0; i < size; i++ ) {
00364             osg::Vec3 tmp(half_size, -( j + offset - half_size ),
00365                           -( i + offset - half_size ) );
00366             tmp.normalize();
00367             tmp = tmp*0.5 - zero_normal;
00368             
00369             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
00370             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
00371             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
00372           }
00373         }
00374         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_X, image);
00375 
00376         image = new osg::Image;
00377         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
00378         ptr = image->data(0, 0);
00379         for (int j = 0; j < size; j++ ) {
00380           for (int i = 0; i < size; i++ ) {
00381             osg::Vec3 tmp(-half_size, -( j + offset - half_size ),
00382                           ( i + offset - half_size ) );
00383             tmp.normalize();
00384             tmp = tmp*0.5 - zero_normal;
00385             
00386             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
00387             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
00388             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
00389           }
00390         }
00391         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_X, image);
00392 
00393         image = new osg::Image;
00394         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
00395         ptr = image->data(0, 0);
00396         for (int j = 0; j < size; j++ ) {
00397           for (int i = 0; i < size; i++ ) {
00398             osg::Vec3 tmp(( i + offset - half_size ), half_size,
00399                           ( j + offset - half_size ) );
00400             tmp.normalize();
00401             tmp = tmp*0.5 - zero_normal;
00402             
00403             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
00404             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
00405             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
00406           }
00407         }
00408         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Y, image);
00409 
00410         image = new osg::Image;
00411         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
00412         ptr = image->data(0, 0);
00413         for (int j = 0; j < size; j++ ) {
00414           for (int i = 0; i < size; i++ ) {
00415             osg::Vec3 tmp(( i + offset - half_size ), -half_size,
00416                           -( j + offset - half_size ) );
00417             tmp.normalize();
00418             tmp = tmp*0.5 - zero_normal;
00419 
00420             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
00421             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
00422             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
00423           }
00424         }
00425         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Y, image);
00426 
00427         image = new osg::Image;
00428         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
00429         ptr = image->data(0, 0);
00430         for (int j = 0; j < size; j++ ) {
00431           for (int i = 0; i < size; i++ ) {
00432             osg::Vec3 tmp(( i + offset - half_size ),
00433                           -( j + offset - half_size ), half_size );
00434             tmp.normalize();
00435             tmp = tmp*0.5 - zero_normal;
00436             
00437             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
00438             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
00439             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
00440           }
00441         }
00442         cubeMap->setImage(osg::TextureCubeMap::POSITIVE_Z, image);
00443 
00444         image = new osg::Image;
00445         image->allocateImage(size, size, 1, GL_RGB, GL_UNSIGNED_BYTE);
00446         ptr = image->data(0, 0);
00447         for (int j = 0; j < size; j++ ) {
00448           for (int i = 0; i < size; i++ ) {
00449             osg::Vec3 tmp(-( i + offset - half_size ),
00450                           -( j + offset - half_size ), -half_size );
00451             tmp.normalize();
00452             tmp = tmp*0.5 - zero_normal;
00453             *ptr++ = (unsigned char)( tmp[ 0 ] * 255 );
00454             *ptr++ = (unsigned char)( tmp[ 1 ] * 255 );
00455             *ptr++ = (unsigned char)( tmp[ 2 ] * 255 );
00456           }
00457         }
00458         cubeMap->setImage(osg::TextureCubeMap::NEGATIVE_Z, image);
00459 
00460         osg::StateSet* state;
00461         state = SGMakeState(texture_path, "overcast.png", "overcast_n.png");
00462         layer_states[SG_CLOUD_OVERCAST] = state;
00463         state = SGMakeState(texture_path, "overcast_top.png", "overcast_top_n.png");
00464         layer_states2[SG_CLOUD_OVERCAST] = state;
00465         
00466         state = SGMakeState(texture_path, "broken.png", "broken_n.png");
00467         layer_states[SG_CLOUD_BROKEN] = state;
00468         layer_states2[SG_CLOUD_BROKEN] = state;
00469         
00470         state = SGMakeState(texture_path, "scattered.png", "scattered_n.png");
00471         layer_states[SG_CLOUD_SCATTERED] = state;
00472         layer_states2[SG_CLOUD_SCATTERED] = state;
00473         
00474         state = SGMakeState(texture_path, "few.png", "few_n.png");
00475         layer_states[SG_CLOUD_FEW] = state;
00476         layer_states2[SG_CLOUD_FEW] = state;
00477         
00478         state = SGMakeState(texture_path, "cirrus.png", "cirrus_n.png");
00479         layer_states[SG_CLOUD_CIRRUS] = state;
00480         layer_states2[SG_CLOUD_CIRRUS] = state;
00481         
00482         layer_states[SG_CLOUD_CLEAR] = 0;
00483         layer_states2[SG_CLOUD_CLEAR] = 0;
00484 #if 1
00485         // experimental optimization that may not make any difference
00486         // at all :/
00487         osg::CopyOp copyOp;
00488         for (int i = 0; i < SG_MAX_CLOUD_COVERAGES; ++i) {
00489             StateAttributeFactory *saf = StateAttributeFactory::instance();
00490             if (layer_states[i].valid()) {
00491                 if (layer_states[i] == layer_states2[i])
00492                     layer_states2[i] = static_cast<osg::StateSet*>(layer_states[i]->clone(copyOp));
00493                 layer_states[i]->setAttribute(saf ->getCullFaceFront());
00494                 layer_states2[i]->setAttribute(saf ->getCullFaceBack());
00495             }
00496         }
00497 #endif
00498     }
00499 
00500     scale = 4000.0;
00501     last_lon = last_lat = -999.0f;
00502 
00503     setTextureOffset(base);
00504     // build the cloud layer
00505     const float layer_scale = layer_span / scale;
00506     const float mpi = SG_PI/4;
00507     
00508     // caclculate the difference between a flat-earth model and 
00509     // a round earth model given the span and altutude ASL of
00510     // the cloud layer. This is the difference in altitude between
00511     // the top of the inverted bowl and the edge of the bowl.
00512     // const float alt_diff = layer_asl * 0.8;
00513     const float layer_to_core = (SG_EARTH_RAD * 1000 + layer_asl);
00514     const float layer_angle = 0.5*layer_span / layer_to_core; // The angle is half the span
00515     const float border_to_core = layer_to_core * cos(layer_angle);
00516     const float alt_diff = layer_to_core - border_to_core;
00517     
00518     for (int i = 0; i < 4; i++) {
00519       if ( layer[i] != NULL ) {
00520         layer_transform->removeChild(layer[i].get()); // automatic delete
00521       }
00522       
00523       vl[i] = new osg::Vec3Array;
00524       cl[i] = new osg::Vec4Array;
00525       tl[i] = new osg::Vec2Array;
00526       
00527       
00528       osg::Vec3 vertex(layer_span*(i-2)/2, -layer_span,
00529                        alt_diff * (sin(i*mpi) - 2));
00530       osg::Vec2 tc(layer_scale * i/4, 0.0f);
00531       osg::Vec4 color(cloudColors[0], (i == 0) ? 0.0f : 0.15f);
00532       
00533       cl[i]->push_back(color);
00534       vl[i]->push_back(vertex);
00535       tl[i]->push_back(tc);
00536       
00537       for (int j = 0; j < 4; j++) {
00538         vertex = osg::Vec3(layer_span*(i-1)/2, layer_span*(j-2)/2,
00539                            alt_diff * (sin((i+1)*mpi) + sin(j*mpi) - 2));
00540         tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale * j/4);
00541         color = osg::Vec4(cloudColors[0],
00542                           ( (j == 0) || (i == 3)) ?  
00543                           ( (j == 0) && (i == 3)) ? 0.0f : 0.15f : 1.0f );
00544         
00545         cl[i]->push_back(color);
00546         vl[i]->push_back(vertex);
00547         tl[i]->push_back(tc);
00548         
00549         vertex = osg::Vec3(layer_span*(i-2)/2, layer_span*(j-1)/2,
00550                            alt_diff * (sin(i*mpi) + sin((j+1)*mpi) - 2) );
00551         tc = osg::Vec2(layer_scale * i/4, layer_scale * (j+1)/4 );
00552         color = osg::Vec4(cloudColors[0],
00553                           ((j == 3) || (i == 0)) ?
00554                           ((j == 3) && (i == 0)) ? 0.0f : 0.15f : 1.0f );
00555         cl[i]->push_back(color);
00556         vl[i]->push_back(vertex);
00557         tl[i]->push_back(tc);
00558       }
00559       
00560       vertex = osg::Vec3(layer_span*(i-1)/2, layer_span, 
00561                          alt_diff * (sin((i+1)*mpi) - 2));
00562       
00563       tc = osg::Vec2(layer_scale * (i+1)/4, layer_scale);
00564       
00565       color = osg::Vec4(cloudColors[0], (i == 3) ? 0.0f : 0.15f );
00566       
00567       cl[i]->push_back( color );
00568       vl[i]->push_back( vertex );
00569       tl[i]->push_back( tc );
00570       
00571       osg::Geometry* geometry = new osg::Geometry;
00572       geometry->setUseDisplayList(false);
00573       geometry->setVertexArray(vl[i].get());
00574       geometry->setNormalBinding(osg::Geometry::BIND_OFF);
00575       geometry->setColorArray(cl[i].get());
00576       geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
00577       geometry->setTexCoordArray(0, tl[i].get());
00578       geometry->addPrimitiveSet(new osg::DrawArrays(GL_TRIANGLE_STRIP, 0, vl[i]->size()));
00579       layer[i] = new osg::Geode;
00580       
00581       std::stringstream sstr;
00582       sstr << "Cloud Layer (" << i << ")";
00583       geometry->setName(sstr.str());
00584       layer[i]->setName(sstr.str());
00585       layer[i]->addDrawable(geometry);
00586       layer_transform->addChild(layer[i].get());
00587     }
00588     
00589     //OSGFIXME: true
00590     if ( layer_states[layer_coverage].valid() ) {
00591       osg::CopyOp copyOp;    // shallow copy
00592       // render bin will be set in reposition
00593       osg::StateSet* stateSet = static_cast<osg::StateSet*>(layer_states2[layer_coverage]->clone(copyOp));
00594       stateSet->setDataVariance(osg::Object::DYNAMIC);
00595       group_top->setStateSet(stateSet);
00596       stateSet = static_cast<osg::StateSet*>(layer_states[layer_coverage]->clone(copyOp));
00597       stateSet->setDataVariance(osg::Object::DYNAMIC);
00598       group_bottom->setStateSet(stateSet);
00599     }
00600 }
00601 
00602 // repaint the cloud layer colors
00603 bool SGCloudLayer::repaint( const SGVec3f& fog_color ) {
00604     osg::Vec4f combineColor(toOsg(fog_color), cloud_alpha);
00605     osg::TexEnvCombine* combiner
00606         = dynamic_cast<osg::TexEnvCombine*>(layer_root->getStateSet()
00607                                             ->getTextureAttribute(1, osg::StateAttribute::TEXENV));
00608     combiner->setConstantColor(combineColor);
00609 
00610     // Set the fog color for the 3D clouds too.
00611     //cloud3dfog->setColor(combineColor);
00612     return true;
00613 }
00614 
00615 // reposition the cloud layer at the specified origin and orientation
00616 // lon specifies a rotation about the Z axis
00617 // lat specifies a rotation about the new Y axis
00618 // spin specifies a rotation about the new Z axis (and orients the
00619 // sunrise/set effects
00620 bool SGCloudLayer::reposition( const SGVec3f& p, const SGVec3f& up, double lon, double lat,
00621                                double alt, double dt )
00622 {
00623     // combine p and asl (meters) to get translation offset
00624     osg::Vec3 asl_offset(toOsg(up));
00625     asl_offset.normalize();
00626     if ( alt <= layer_asl ) {
00627         asl_offset *= layer_asl;
00628     } else {
00629         asl_offset *= layer_asl + layer_thickness;
00630     }
00631 
00632     // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
00633     //      << "," << asl_offset[2] << endl;
00634     asl_offset += toOsg(p);
00635     // cout << "  asl_offset = " << asl_offset[0] << "," << asl_offset[1]
00636     //      << "," << asl_offset[2] << endl;
00637 
00638     osg::Matrix T, LON, LAT;
00639     // Translate to zero elevation
00640     // Point3D zero_elev = current_view.get_cur_zero_elev();
00641     T.makeTranslate( asl_offset );
00642 
00643     // printf("  Translated to %.2f %.2f %.2f\n", 
00644     //        zero_elev.x, zero_elev.y, zero_elev.z );
00645 
00646     // Rotate to proper orientation
00647     // printf("  lon = %.2f  lat = %.2f\n", 
00648     //        lon * SGD_RADIANS_TO_DEGREES,
00649     //        lat * SGD_RADIANS_TO_DEGREES);
00650     LON.makeRotate(lon, osg::Vec3(0, 0, 1));
00651 
00652     // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
00653     //             0.0, 1.0, 0.0 );
00654     LAT.makeRotate(90.0 * SGD_DEGREES_TO_RADIANS - lat, osg::Vec3(0, 1, 0));
00655 
00656     layer_transform->setMatrix( LAT*LON*T );
00657 
00658     // The layers need to be drawn in order because they are
00659     // translucent, but OSG transparency sorting doesn't work because
00660     // the cloud polys are huge. However, the ordering is simple: the
00661     // bottom polys should be drawn from high altitude to low, and the
00662     // top polygons from low to high. The altitude can be used
00663     // directly to order the polygons!
00664     group_bottom->getStateSet()->setRenderBinDetails(-(int)layer_asl,
00665                                                      "RenderBin");
00666     group_top->getStateSet()->setRenderBinDetails((int)layer_asl,
00667                                                   "RenderBin");
00668     if ( alt <= layer_asl ) {
00669       layer_root->setSingleChildOn(0);
00670     } else if ( alt >= layer_asl + layer_thickness ) {
00671       layer_root->setSingleChildOn(1);
00672     } else {
00673       layer_root->setAllChildrenOff();
00674     }
00675         
00676 
00677     // now calculate update texture coordinates
00678     if ( last_lon < -900 ) {
00679         last_lon = lon;
00680         last_lat = lat;
00681     }
00682 
00683     double sp_dist = speed*dt;
00684 
00685     if ( lon != last_lon || lat != last_lat || sp_dist != 0 ) {
00686         Point3D start( last_lon, last_lat, 0.0 );
00687         Point3D dest( lon, lat, 0.0 );
00688         double course = 0.0, dist = 0.0;
00689 
00690         calc_gc_course_dist( dest, start, &course, &dist );
00691         // cout << "course = " << course << ", dist = " << dist << endl;
00692 
00693         // if start and dest are too close together,
00694         // calc_gc_course_dist() can return a course of "nan".  If
00695         // this happens, lets just use the last known good course.
00696         // This is a hack, and it would probably be better to make
00697         // calc_gc_course_dist() more robust.
00698         if ( isnan(course) ) {
00699             course = last_course;
00700         } else {
00701             last_course = course;
00702         }
00703 
00704         // calculate cloud movement due to external forces
00705         double ax = 0.0, ay = 0.0, bx = 0.0, by = 0.0;
00706 
00707         if (dist > 0.0) {
00708             ax = cos(course) * dist;
00709             ay = sin(course) * dist;
00710         }
00711 
00712         if (sp_dist > 0) {
00713             bx = cos((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
00714             by = sin((180.0-direction) * SGD_DEGREES_TO_RADIANS) * sp_dist;
00715         }
00716 
00717 
00718         double xoff = (ax + bx) / (2 * scale);
00719         double yoff = (ay + by) / (2 * scale);
00720 
00721 //        const float layer_scale = layer_span / scale;
00722 
00723         // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
00724         base[0] += xoff;
00725 
00726         // the while loops can lead to *long* pauses if base[0] comes
00727         // with a bogus value.
00728         // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
00729         // while ( base[0] < 0.0 ) { base[0] += 1.0; }
00730         if ( base[0] > -10.0 && base[0] < 10.0 ) {
00731             base[0] -= (int)base[0];
00732         } else {
00733             SG_LOG(SG_ASTRO, SG_DEBUG,
00734                 "Error: base = " << base[0] << "," << base[1] <<
00735                 " course = " << course << " dist = " << dist );
00736             base[0] = 0.0;
00737         }
00738 
00739         base[1] += yoff;
00740         // the while loops can lead to *long* pauses if base[0] comes
00741         // with a bogus value.
00742         // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
00743         // while ( base[1] < 0.0 ) { base[1] += 1.0; }
00744         if ( base[1] > -10.0 && base[1] < 10.0 ) {
00745             base[1] -= (int)base[1];
00746         } else {
00747             SG_LOG(SG_ASTRO, SG_DEBUG,
00748                     "Error: base = " << base[0] << "," << base[1] <<
00749                     " course = " << course << " dist = " << dist );
00750             base[1] = 0.0;
00751         }
00752 
00753         // cout << "base = " << base[0] << "," << base[1] << endl;
00754 
00755         setTextureOffset(base);
00756         last_lon = lon;
00757         last_lat = lat;
00758     }
00759 
00760     layer3D->reposition( p, up, lon, lat, dt, layer_asl);
00761     return true;
00762 }
00763 
00764 void SGCloudLayer::set_enable3dClouds(bool enable) {
00765      
00766     if (layer3D->defined3D && enable) {
00767         cloud_root->setChildValue(layer3D->getNode(), true);
00768         cloud_root->setChildValue(layer_root.get(),   false);
00769     } else {
00770         cloud_root->setChildValue(layer3D->getNode(), false);
00771         cloud_root->setChildValue(layer_root.get(),   true);
00772     }
00773 }