simgear/scene/tgdb/pt_lights.cxx

   1 // pt_lights.cxx -- build a 'directional' light on the fly
   2 //
   3 // Written by Curtis Olson, started March 2002.
   4 //
   5 // Copyright (C) 2002  Curtis L. Olson  - http://www.flightgear.org/~curt
   6 //
   7 // This program is free software; you can redistribute it and/or
   8 // modify it under the terms of the GNU General Public License as
   9 // published by the Free Software Foundation; either version 2 of the
  10 // License, or (at your option) any later version.
  11 //
  12 // This program 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 "pt_lights.hxx"
  28
  29 #include <map>
  30 #include <boost/tuple/tuple_comparison.hpp>
  31
  32 #include <osg/Array>
  33 #include <osg/Geometry>
  34 #include <osg/CullFace>
  35 #include <osg/Geode>
  36 #include <osg/MatrixTransform>
  37 #include <osg/NodeCallback>
  38 #include <osg/NodeVisitor>
  39 #include <osg/Texture2D>
  40 #include <osg/AlphaFunc>
  41 #include <osg/BlendFunc>
  42 #include <osg/TexEnv>
  43 #include <osg/Sequence>
  44 #include <osg/PolygonMode>
  45 #include <osg/Fog>
  46 #include <osg/FragmentProgram>
  47 #include <osg/VertexProgram>
  48 #include <osg/Point>
  49 #include <osg/PointSprite>
  50 #include <osg/Material>
  51 #include <osg/Group>
  52 #include <osg/StateSet>
  53
  54 #include <osgUtil/CullVisitor>
  55
  56 #include <OpenThreads/Mutex>
  57 #include <OpenThreads/ScopedLock>
  58
  59 #include <simgear/math/sg_random.h>
  60 #include <simgear/debug/logstream.hxx>
  61 #include <simgear/scene/util/RenderConstants.hxx>
  62 #include <simgear/scene/util/SGEnlargeBoundingBox.hxx>
  63 #include <simgear/scene/util/StateAttributeFactory.hxx>
  64
  65 #include <simgear/scene/material/Effect.hxx>
  66 #include <simgear/scene/material/EffectGeode.hxx>
  67 #include <simgear/scene/material/Technique.hxx>
  68 #include <simgear/scene/material/Pass.hxx>
  69
  70 #include "SGVasiDrawable.hxx"
  71
  72 using OpenThreads::Mutex;
  73 using OpenThreads::ScopedLock;
  74
  75 using namespace osg;
  76 using namespace simgear;
  77
  78 static void
  79 setPointSpriteImage(unsigned char* data, unsigned log2resolution,
  80                     unsigned charsPerPixel)
  81 {
  82   int env_tex_res = (1 << log2resolution);
  83   for (int i = 0; i < env_tex_res; ++i) {
  84     for (int j = 0; j < env_tex_res; ++j) {
  85       int xi = 2*i + 1 - env_tex_res;
  86       int yi = 2*j + 1 - env_tex_res;
  87       if (xi < 0)
  88         xi = -xi;
  89       if (yi < 0)
  90         yi = -yi;
  91
  92       xi -= 1;
  93       yi -= 1;
  94
  95       if (xi < 0)
  96         xi = 0;
  97       if (yi < 0)
  98         yi = 0;
  99
 100       float x = 1.5*xi/(float)(env_tex_res);
 101       float y = 1.5*yi/(float)(env_tex_res);
 102       //       float x = 2*xi/(float)(env_tex_res);
 103       //       float y = 2*yi/(float)(env_tex_res);
 104       float dist = sqrt(x*x + y*y);
 105       float bright = SGMiscf::clip(255*(1-dist), 0, 255);
 106       for (unsigned l = 0; l < charsPerPixel; ++l)
 107         data[charsPerPixel*(i*env_tex_res + j) + l] = (unsigned char)bright;
 108     }
 109   }
 110 }
 111
 112 static osg::Image*
 113 getPointSpriteImage(int logResolution)
 114 {
 115   osg::Image* image = new osg::Image;
 116
 117   osg::Image::MipmapDataType mipmapOffsets;
 118   unsigned off = 0;
 119   for (int i = logResolution; 0 <= i; --i) {
 120     unsigned res = 1 << i;
 121     off += res*res;
 122     mipmapOffsets.push_back(off);
 123   }
 124
 125   int env_tex_res = (1 << logResolution);
 126
 127   unsigned char* imageData = new unsigned char[off];
 128   image->setImage(env_tex_res, env_tex_res, 1,
 129                   GL_ALPHA, GL_ALPHA, GL_UNSIGNED_BYTE, imageData,
 130                   osg::Image::USE_NEW_DELETE);
 131   image->setMipmapLevels(mipmapOffsets);
 132
 133   for (int k = logResolution; 0 <= k; --k) {
 134     setPointSpriteImage(image->getMipmapData(logResolution - k), k, 1);
 135   }
 136
 137   return image;
 138 }
 139
 140 static Mutex lightMutex;
 141
 142 static osg::Texture2D*
 143 gen_standard_light_sprite(void)
 144 {
 145   // Always called from when the lightMutex is already taken
 146   static osg::ref_ptr<osg::Texture2D> texture;
 147   if (texture.valid())
 148     return texture.get();
 149
 150   texture = new osg::Texture2D;
 151   texture->setImage(getPointSpriteImage(6));
 152   texture->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP);
 153   texture->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP);
 154
 155   return texture.get();
 156 }
 157
 158 namespace
 159 {
 160 typedef boost::tuple<float, osg::Vec3, float, float, bool> PointParams;
 161 typedef std::map<PointParams, ref_ptr<Effect> > EffectMap;
 162
 163 EffectMap effectMap;
 164
 165 ref_ptr<PolygonMode> polyMode = new PolygonMode(PolygonMode::FRONT,
 166                                                 PolygonMode::POINT);
 167 ref_ptr<PointSprite> pointSprite = new PointSprite;
 168 }
 169
 170 Effect* getLightEffect(float size, const Vec3& attenuation,
 171                        float minSize, float maxSize, bool directional)
 172 {
 173     PointParams pointParams(size, attenuation, minSize, maxSize, directional);
 174     ScopedLock<Mutex> lock(lightMutex);
 175     EffectMap::iterator eitr = effectMap.find(pointParams);
 176     if (eitr != effectMap.end())
 177         return eitr->second.get();
 178     // Basic stuff; no sprite or attenuation support
 179     Pass *basicPass = new Pass;
 180     basicPass->setRenderBinDetails(POINT_LIGHTS_BIN, "DepthSortedBin");
 181     basicPass->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 182     StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 183     basicPass->setAttributeAndModes(attrFact->getStandardBlendFunc());
 184     basicPass->setAttributeAndModes(attrFact->getStandardAlphaFunc());
 185     if (directional) {
 186         basicPass->setAttributeAndModes(attrFact->getCullFaceBack());
 187         basicPass->setAttribute(polyMode.get());
 188     }
 189     Pass *attenuationPass = clone(basicPass, CopyOp::SHALLOW_COPY);
 190     osg::Point* point = new osg::Point;
 191     point->setMinSize(minSize);
 192     point->setMaxSize(maxSize);
 193     point->setSize(size);
 194     point->setDistanceAttenuation(attenuation);
 195     attenuationPass->setAttributeAndModes(point);
 196     Pass *spritePass = clone(basicPass, CopyOp::SHALLOW_COPY);
 197     spritePass->setTextureAttributeAndModes(0, pointSprite.get(),
 198                                             osg::StateAttribute::ON);
 199     Texture2D* texture = gen_standard_light_sprite();
 200     spritePass->setTextureAttribute(0, texture);
 201     spritePass->setTextureMode(0, GL_TEXTURE_2D,
 202                                osg::StateAttribute::ON);
 203     spritePass->setTextureAttribute(0, attrFact->getStandardTexEnv());
 204     Pass *combinedPass = clone(spritePass, CopyOp::SHALLOW_COPY);
 205     combinedPass->setAttributeAndModes(point);
 206     Effect* effect = new Effect;
 207     std::vector<std::string> parameterExtensions;
 208
 209     if (SGSceneFeatures::instance()->getEnablePointSpriteLights())
 210     {
 211         std::vector<std::string> combinedExtensions;
 212         combinedExtensions.push_back("GL_ARB_point_sprite");
 213         combinedExtensions.push_back("GL_ARB_point_parameters");
 214         Technique* combinedTniq = new Technique;
 215         combinedTniq->passes.push_back(combinedPass);
 216         combinedTniq->setGLExtensionsPred(2.0, combinedExtensions);
 217         effect->techniques.push_back(combinedTniq);
 218         std::vector<std::string> spriteExtensions;
 219         spriteExtensions.push_back(combinedExtensions.front());
 220         Technique* spriteTniq = new Technique;
 221         spriteTniq->passes.push_back(spritePass);
 222         spriteTniq->setGLExtensionsPred(2.0, spriteExtensions);
 223         effect->techniques.push_back(spriteTniq);
 224         parameterExtensions.push_back(combinedExtensions.back());
 225     }
 226
 227     Technique* parameterTniq = new Technique;
 228     parameterTniq->passes.push_back(attenuationPass);
 229     parameterTniq->setGLExtensionsPred(1.4, parameterExtensions);
 230     effect->techniques.push_back(parameterTniq);
 231     Technique* basicTniq = new Technique(true);
 232     basicTniq->passes.push_back(basicPass);
 233     effect->techniques.push_back(basicTniq);
 234     effectMap.insert(std::make_pair(pointParams, effect));
 235     return effect;
 236 }
 237
 238
 239 osg::Drawable*
 240 SGLightFactory::getLightDrawable(const SGLightBin::Light& light)
 241 {
 242   osg::Vec3Array* vertices = new osg::Vec3Array;
 243   osg::Vec4Array* colors = new osg::Vec4Array;
 244
 245   vertices->push_back(toOsg(light.position));
 246   colors->push_back(toOsg(light.color));
 247
 248   osg::Geometry* geometry = new osg::Geometry;
 249   geometry->setVertexArray(vertices);
 250   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 251   geometry->setColorArray(colors);
 252   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 253
 254   // Enlarge the bounding box to avoid such light nodes being victim to
 255   // small feature culling.
 256   geometry->setComputeBoundingBoxCallback(new SGEnlargeBoundingBox(1));
 257
 258   osg::DrawArrays* drawArrays;
 259   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::POINTS,
 260                                    0, vertices->size());
 261   geometry->addPrimitiveSet(drawArrays);
 262   return geometry;
 263 }
 264
 265 osg::Drawable*
 266 SGLightFactory::getLightDrawable(const SGDirectionalLightBin::Light& light)
 267 {
 268   osg::Vec3Array* vertices = new osg::Vec3Array;
 269   osg::Vec4Array* colors = new osg::Vec4Array;
 270
 271   SGVec4f visibleColor(light.color);
 272   SGVec4f invisibleColor(visibleColor[0], visibleColor[1],
 273                          visibleColor[2], 0);
 274   SGVec3f normal = normalize(light.normal);
 275   SGVec3f perp1 = perpendicular(normal);
 276   SGVec3f perp2 = cross(normal, perp1);
 277   SGVec3f position = light.position;
 278   vertices->push_back(toOsg(position));
 279   vertices->push_back(toOsg(position + perp1));
 280   vertices->push_back(toOsg(position + perp2));
 281   colors->push_back(toOsg(visibleColor));
 282   colors->push_back(toOsg(invisibleColor));
 283   colors->push_back(toOsg(invisibleColor));
 284
 285   osg::Geometry* geometry = new osg::Geometry;
 286   geometry->setVertexArray(vertices);
 287   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 288   geometry->setColorArray(colors);
 289   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 290   // Enlarge the bounding box to avoid such light nodes being victim to
 291   // small feature culling.
 292   geometry->setComputeBoundingBoxCallback(new SGEnlargeBoundingBox(1));
 293
 294   osg::DrawArrays* drawArrays;
 295   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES,
 296                                    0, vertices->size());
 297   geometry->addPrimitiveSet(drawArrays);
 298   return geometry;
 299 }
 300
 301 namespace
 302 {
 303   ref_ptr<StateSet> simpleLightSS;
 304 }
 305 osg::Drawable*
 306 SGLightFactory::getLights(const SGLightBin& lights, unsigned inc, float alphaOff)
 307 {
 308   if (lights.getNumLights() <= 0)
 309     return 0;
 310
 311   osg::Vec3Array* vertices = new osg::Vec3Array;
 312   osg::Vec4Array* colors = new osg::Vec4Array;
 313
 314   for (unsigned i = 0; i < lights.getNumLights(); i += inc) {
 315     vertices->push_back(toOsg(lights.getLight(i).position));
 316     SGVec4f color = lights.getLight(i).color;
 317     color[3] = SGMiscf::max(0, SGMiscf::min(1, color[3] + alphaOff));
 318     colors->push_back(toOsg(color));
 319   }
 320
 321   osg::Geometry* geometry = new osg::Geometry;
 322
 323   geometry->setVertexArray(vertices);
 324   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 325   geometry->setColorArray(colors);
 326   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 327
 328   osg::DrawArrays* drawArrays;
 329   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::POINTS,
 330                                    0, vertices->size());
 331   geometry->addPrimitiveSet(drawArrays);
 332
 333   {
 334     ScopedLock<Mutex> lock(lightMutex);
 335     if (!simpleLightSS.valid()) {
 336       StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 337       simpleLightSS = new StateSet;
 338       simpleLightSS->setRenderBinDetails(POINT_LIGHTS_BIN, "DepthSortedBin");
 339       simpleLightSS->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 340       simpleLightSS->setAttributeAndModes(attrFact->getStandardBlendFunc());
 341       simpleLightSS->setAttributeAndModes(attrFact->getStandardAlphaFunc());
 342     }
 343   }
 344   geometry->setStateSet(simpleLightSS.get());
 345   return geometry;
 346 }
 347
 348
 349 osg::Drawable*
 350 SGLightFactory::getLights(const SGDirectionalLightBin& lights)
 351 {
 352   if (lights.getNumLights() <= 0)
 353     return 0;
 354
 355   osg::Vec3Array* vertices = new osg::Vec3Array;
 356   osg::Vec4Array* colors = new osg::Vec4Array;
 357
 358   for (unsigned i = 0; i < lights.getNumLights(); ++i) {
 359     SGVec4f visibleColor(lights.getLight(i).color);
 360     SGVec4f invisibleColor(visibleColor[0], visibleColor[1],
 361                            visibleColor[2], 0);
 362     SGVec3f normal = normalize(lights.getLight(i).normal);
 363     SGVec3f perp1 = perpendicular(normal);
 364     SGVec3f perp2 = cross(normal, perp1);
 365     SGVec3f position = lights.getLight(i).position;
 366     vertices->push_back(toOsg(position));
 367     vertices->push_back(toOsg(position + perp1));
 368     vertices->push_back(toOsg(position + perp2));
 369     colors->push_back(toOsg(visibleColor));
 370     colors->push_back(toOsg(invisibleColor));
 371     colors->push_back(toOsg(invisibleColor));
 372   }
 373
 374   osg::Geometry* geometry = new osg::Geometry;
 375
 376   geometry->setVertexArray(vertices);
 377   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 378   geometry->setColorArray(colors);
 379   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 380
 381   osg::DrawArrays* drawArrays;
 382   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES,
 383                                    0, vertices->size());
 384   geometry->addPrimitiveSet(drawArrays);
 385   return geometry;
 386 }
 387
 388 static SGVasiDrawable*
 389 buildVasi(const SGDirectionalLightBin& lights, const SGVec3f& up,
 390        const SGVec4f& red, const SGVec4f& white)
 391 {
 392   unsigned count = lights.getNumLights();
 393   if ( count == 4 ) {
 394     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 395
 396     // PAPI configuration
 397     // papi D
 398     drawable->addLight(lights.getLight(0).position,
 399                        lights.getLight(0).normal, up, 3.5);
 400     // papi C
 401     drawable->addLight(lights.getLight(1).position,
 402                        lights.getLight(1).normal, up, 3.167);
 403     // papi B
 404     drawable->addLight(lights.getLight(2).position,
 405                        lights.getLight(2).normal, up, 2.833);
 406     // papi A
 407     drawable->addLight(lights.getLight(3).position,
 408                        lights.getLight(3).normal, up, 2.5);
 409     return drawable;
 410   }
 411   else if (count == 12) {
 412     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 413
 414     // probably vasi, first 6 are downwind bar (2.5 deg)
 415     for (unsigned i = 0; i < 6; ++i)
 416       drawable->addLight(lights.getLight(i).position,
 417                          lights.getLight(i).normal, up, 2.5);
 418     // last 6 are upwind bar (3.0 deg)
 419     for (unsigned i = 6; i < 12; ++i)
 420       drawable->addLight(lights.getLight(i).position,
 421                          lights.getLight(i).normal, up, 3.0);
 422
 423     return drawable;
 424   } else {
 425     // fail safe
 426     SG_LOG(SG_TERRAIN, SG_ALERT,
 427            "unknown vasi/papi configuration, count = " << count);
 428     return 0;
 429   }
 430 }
 431
 432 osg::Drawable*
 433 SGLightFactory::getVasi(const SGVec3f& up, const SGDirectionalLightBin& lights,
 434                         const SGVec4f& red, const SGVec4f& white)
 435 {
 436   SGVasiDrawable* drawable = buildVasi(lights, up, red, white);
 437   if (!drawable)
 438     return 0;
 439
 440   osg::StateSet* stateSet = drawable->getOrCreateStateSet();
 441   stateSet->setRenderBinDetails(POINT_LIGHTS_BIN, "DepthSortedBin");
 442   stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 443
 444   osg::BlendFunc* blendFunc = new osg::BlendFunc;
 445   stateSet->setAttribute(blendFunc);
 446   stateSet->setMode(GL_BLEND, osg::StateAttribute::ON);
 447
 448   osg::AlphaFunc* alphaFunc;
 449   alphaFunc = new osg::AlphaFunc(osg::AlphaFunc::GREATER, 0.01);
 450   stateSet->setAttribute(alphaFunc);
 451   stateSet->setMode(GL_ALPHA_TEST, osg::StateAttribute::ON);
 452
 453   return drawable;
 454 }
 455
 456 osg::Node*
 457 SGLightFactory::getSequenced(const SGDirectionalLightBin& lights)
 458 {
 459   if (lights.getNumLights() <= 0)
 460     return 0;
 461
 462   // generate a repeatable random seed
 463   sg_srandom(unsigned(lights.getLight(0).position[0]));
 464   float flashTime = 2e-2 + 5e-3*sg_random();
 465   osg::Sequence* sequence = new osg::Sequence;
 466   sequence->setDefaultTime(flashTime);
 467   Effect* effect = getLightEffect(10.0f, osg::Vec3(1.0, 0.0001, 0.00000001),
 468                                   6.0f, 10.0f, true);
 469   for (int i = lights.getNumLights() - 1; 0 <= i; --i) {
 470     EffectGeode* egeode = new EffectGeode;
 471     egeode->setEffect(effect);
 472     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 473     sequence->addChild(egeode, flashTime);
 474   }
 475   sequence->addChild(new osg::Group, 1 + 1e-1*sg_random());
 476   sequence->setInterval(osg::Sequence::LOOP, 0, -1);
 477   sequence->setDuration(1.0f, -1);
 478   sequence->setMode(osg::Sequence::START);
 479   sequence->setSync(true);
 480   return sequence;
 481 }
 482
 483 osg::Node*
 484 SGLightFactory::getOdal(const SGLightBin& lights)
 485 {
 486   if (lights.getNumLights() < 2)
 487     return 0;
 488
 489   // generate a repeatable random seed
 490   sg_srandom(unsigned(lights.getLight(0).position[0]));
 491   float flashTime = 2e-2 + 5e-3*sg_random();
 492   osg::Sequence* sequence = new osg::Sequence;
 493   sequence->setDefaultTime(flashTime);
 494   Effect* effect = getLightEffect(10.0f, osg::Vec3(1.0, 0.0001, 0.00000001),
 495                                   6.0, 10.0, false);
 496   // centerline lights
 497   for (int i = lights.getNumLights() - 1; 2 <= i; --i) {
 498     EffectGeode* egeode = new EffectGeode;
 499     egeode->setEffect(effect);
 500     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 501     sequence->addChild(egeode, flashTime);
 502   }
 503   // runway end lights
 504   osg::Group* group = new osg::Group;
 505   for (unsigned i = 0; i < 2; ++i) {
 506     EffectGeode* egeode = new EffectGeode;
 507     egeode->setEffect(effect);
 508     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 509     group->addChild(egeode);
 510   }
 511   sequence->addChild(group, flashTime);
 512
 513   // add an extra empty group for a break
 514   sequence->addChild(new osg::Group, 9 + 1e-1*sg_random());
 515   sequence->setInterval(osg::Sequence::LOOP, 0, -1);
 516   sequence->setDuration(1.0f, -1);
 517   sequence->setMode(osg::Sequence::START);
 518   sequence->setSync(true);
 519
 520   return sequence;
 521 }