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/OsgMath.hxx>
  64 #include <simgear/scene/util/StateAttributeFactory.hxx>
  65
  66 #include <simgear/scene/material/Effect.hxx>
  67 #include <simgear/scene/material/EffectGeode.hxx>
  68 #include <simgear/scene/material/Technique.hxx>
  69 #include <simgear/scene/material/Pass.hxx>
  70
  71 #include "SGVasiDrawable.hxx"
  72
  73 using OpenThreads::Mutex;
  74 using OpenThreads::ScopedLock;
  75
  76 using namespace osg;
  77 using namespace simgear;
  78
  79 static void
  80 setPointSpriteImage(unsigned char* data, unsigned log2resolution,
  81                     unsigned charsPerPixel)
  82 {
  83   int env_tex_res = (1 << log2resolution);
  84   for (int i = 0; i < env_tex_res; ++i) {
  85     for (int j = 0; j < env_tex_res; ++j) {
  86       int xi = 2*i + 1 - env_tex_res;
  87       int yi = 2*j + 1 - env_tex_res;
  88       if (xi < 0)
  89         xi = -xi;
  90       if (yi < 0)
  91         yi = -yi;
  92
  93       xi -= 1;
  94       yi -= 1;
  95
  96       if (xi < 0)
  97         xi = 0;
  98       if (yi < 0)
  99         yi = 0;
 100
 101       float x = 1.5*xi/(float)(env_tex_res);
 102       float y = 1.5*yi/(float)(env_tex_res);
 103       //       float x = 2*xi/(float)(env_tex_res);
 104       //       float y = 2*yi/(float)(env_tex_res);
 105       float dist = sqrt(x*x + y*y);
 106       float bright = SGMiscf::clip(255*(1-dist), 0, 255);
 107       for (unsigned l = 0; l < charsPerPixel; ++l)
 108         data[charsPerPixel*(i*env_tex_res + j) + l] = (unsigned char)bright;
 109     }
 110   }
 111 }
 112
 113 static osg::Image*
 114 getPointSpriteImage(int logResolution)
 115 {
 116   osg::Image* image = new osg::Image;
 117
 118   osg::Image::MipmapDataType mipmapOffsets;
 119   unsigned off = 0;
 120   for (int i = logResolution; 0 <= i; --i) {
 121     unsigned res = 1 << i;
 122     off += res*res;
 123     mipmapOffsets.push_back(off);
 124   }
 125
 126   int env_tex_res = (1 << logResolution);
 127
 128   unsigned char* imageData = new unsigned char[off];
 129   image->setImage(env_tex_res, env_tex_res, 1,
 130                   GL_ALPHA, GL_ALPHA, GL_UNSIGNED_BYTE, imageData,
 131                   osg::Image::USE_NEW_DELETE);
 132   image->setMipmapLevels(mipmapOffsets);
 133
 134   for (int k = logResolution; 0 <= k; --k) {
 135     setPointSpriteImage(image->getMipmapData(logResolution - k), k, 1);
 136   }
 137
 138   return image;
 139 }
 140
 141 static Mutex lightMutex;
 142
 143 static osg::Texture2D*
 144 gen_standard_light_sprite(void)
 145 {
 146   // Always called from when the lightMutex is already taken
 147   static osg::ref_ptr<osg::Texture2D> texture;
 148   if (texture.valid())
 149     return texture.get();
 150
 151   texture = new osg::Texture2D;
 152   texture->setImage(getPointSpriteImage(6));
 153   texture->setWrap(osg::Texture::WRAP_S, osg::Texture::CLAMP);
 154   texture->setWrap(osg::Texture::WRAP_T, osg::Texture::CLAMP);
 155
 156   return texture.get();
 157 }
 158
 159 namespace
 160 {
 161 typedef boost::tuple<float, osg::Vec3, float, float, bool> PointParams;
 162 typedef std::map<PointParams, observer_ptr<Effect> > EffectMap;
 163
 164 EffectMap effectMap;
 165
 166 ref_ptr<PolygonMode> polyMode = new PolygonMode(PolygonMode::FRONT,
 167                                                 PolygonMode::POINT);
 168 ref_ptr<PointSprite> pointSprite = new PointSprite;
 169 }
 170
 171 Effect* getLightEffect(float size, const Vec3& attenuation,
 172                        float minSize, float maxSize, bool directional)
 173 {
 174     PointParams pointParams(size, attenuation, minSize, maxSize, directional);
 175     ScopedLock<Mutex> lock(lightMutex);
 176     EffectMap::iterator eitr = effectMap.find(pointParams);
 177     if ((eitr != effectMap.end())&&
 178         eitr->second.valid())
 179         return eitr->second.get();
 180     // Basic stuff; no sprite or attenuation support
 181     Pass *basicPass = new Pass;
 182     basicPass->setRenderBinDetails(POINT_LIGHTS_BIN, "DepthSortedBin");
 183     basicPass->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 184     StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 185     basicPass->setAttributeAndModes(attrFact->getStandardBlendFunc());
 186     basicPass->setAttributeAndModes(attrFact->getStandardAlphaFunc());
 187     if (directional) {
 188         basicPass->setAttributeAndModes(attrFact->getCullFaceBack());
 189         basicPass->setAttribute(polyMode.get());
 190     }
 191     Pass *attenuationPass = clone(basicPass, CopyOp::SHALLOW_COPY);
 192     osg::Point* point = new osg::Point;
 193     point->setMinSize(minSize);
 194     point->setMaxSize(maxSize);
 195     point->setSize(size);
 196     point->setDistanceAttenuation(attenuation);
 197     attenuationPass->setAttributeAndModes(point);
 198     Pass *spritePass = clone(basicPass, CopyOp::SHALLOW_COPY);
 199     spritePass->setTextureAttributeAndModes(0, pointSprite.get(),
 200                                             osg::StateAttribute::ON);
 201     Texture2D* texture = gen_standard_light_sprite();
 202     spritePass->setTextureAttribute(0, texture);
 203     spritePass->setTextureMode(0, GL_TEXTURE_2D,
 204                                osg::StateAttribute::ON);
 205     spritePass->setTextureAttribute(0, attrFact->getStandardTexEnv());
 206     Pass *combinedPass = clone(spritePass, CopyOp::SHALLOW_COPY);
 207     combinedPass->setAttributeAndModes(point);
 208     ref_ptr<Effect> effect = new Effect;
 209     std::vector<std::string> parameterExtensions;
 210
 211     if (SGSceneFeatures::instance()->getEnablePointSpriteLights())
 212     {
 213         std::vector<std::string> combinedExtensions;
 214         combinedExtensions.push_back("GL_ARB_point_sprite");
 215         combinedExtensions.push_back("GL_ARB_point_parameters");
 216         Technique* combinedTniq = new Technique;
 217         combinedTniq->passes.push_back(combinedPass);
 218         combinedTniq->setGLExtensionsPred(2.0, combinedExtensions);
 219         effect->techniques.push_back(combinedTniq);
 220         std::vector<std::string> spriteExtensions;
 221         spriteExtensions.push_back(combinedExtensions.front());
 222         Technique* spriteTniq = new Technique;
 223         spriteTniq->passes.push_back(spritePass);
 224         spriteTniq->setGLExtensionsPred(2.0, spriteExtensions);
 225         effect->techniques.push_back(spriteTniq);
 226         parameterExtensions.push_back(combinedExtensions.back());
 227     }
 228
 229     Technique* parameterTniq = new Technique;
 230     parameterTniq->passes.push_back(attenuationPass);
 231     parameterTniq->setGLExtensionsPred(1.4, parameterExtensions);
 232     effect->techniques.push_back(parameterTniq);
 233     Technique* basicTniq = new Technique(true);
 234     basicTniq->passes.push_back(basicPass);
 235     effect->techniques.push_back(basicTniq);
 236     if (eitr == effectMap.end())
 237         effectMap.insert(std::make_pair(pointParams, effect));
 238     else
 239         eitr->second = effect; // update existing, but empty observer
 240     return effect.release();
 241 }
 242
 243
 244 osg::Drawable*
 245 SGLightFactory::getLightDrawable(const SGLightBin::Light& light)
 246 {
 247   osg::Vec3Array* vertices = new osg::Vec3Array;
 248   osg::Vec4Array* colors = new osg::Vec4Array;
 249
 250   vertices->push_back(toOsg(light.position));
 251   colors->push_back(toOsg(light.color));
 252
 253   osg::Geometry* geometry = new osg::Geometry;
 254   geometry->setVertexArray(vertices);
 255   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 256   geometry->setColorArray(colors);
 257   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 258
 259   // Enlarge the bounding box to avoid such light nodes being victim to
 260   // small feature culling.
 261   geometry->setComputeBoundingBoxCallback(new SGEnlargeBoundingBox(1));
 262
 263   osg::DrawArrays* drawArrays;
 264   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::POINTS,
 265                                    0, vertices->size());
 266   geometry->addPrimitiveSet(drawArrays);
 267   return geometry;
 268 }
 269
 270 osg::Drawable*
 271 SGLightFactory::getLightDrawable(const SGDirectionalLightBin::Light& light)
 272 {
 273   osg::Vec3Array* vertices = new osg::Vec3Array;
 274   osg::Vec4Array* colors = new osg::Vec4Array;
 275
 276   SGVec4f visibleColor(light.color);
 277   SGVec4f invisibleColor(visibleColor[0], visibleColor[1],
 278                          visibleColor[2], 0);
 279   SGVec3f normal = normalize(light.normal);
 280   SGVec3f perp1 = perpendicular(normal);
 281   SGVec3f perp2 = cross(normal, perp1);
 282   SGVec3f position = light.position;
 283   vertices->push_back(toOsg(position));
 284   vertices->push_back(toOsg(position + perp1));
 285   vertices->push_back(toOsg(position + perp2));
 286   colors->push_back(toOsg(visibleColor));
 287   colors->push_back(toOsg(invisibleColor));
 288   colors->push_back(toOsg(invisibleColor));
 289
 290   osg::Geometry* geometry = new osg::Geometry;
 291   geometry->setVertexArray(vertices);
 292   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 293   geometry->setColorArray(colors);
 294   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 295   // Enlarge the bounding box to avoid such light nodes being victim to
 296   // small feature culling.
 297   geometry->setComputeBoundingBoxCallback(new SGEnlargeBoundingBox(1));
 298
 299   osg::DrawArrays* drawArrays;
 300   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES,
 301                                    0, vertices->size());
 302   geometry->addPrimitiveSet(drawArrays);
 303   return geometry;
 304 }
 305
 306 namespace
 307 {
 308   ref_ptr<StateSet> simpleLightSS;
 309 }
 310 osg::Drawable*
 311 SGLightFactory::getLights(const SGLightBin& lights, unsigned inc, float alphaOff)
 312 {
 313   if (lights.getNumLights() <= 0)
 314     return 0;
 315
 316   osg::Vec3Array* vertices = new osg::Vec3Array;
 317   osg::Vec4Array* colors = new osg::Vec4Array;
 318
 319   for (unsigned i = 0; i < lights.getNumLights(); i += inc) {
 320     vertices->push_back(toOsg(lights.getLight(i).position));
 321     SGVec4f color = lights.getLight(i).color;
 322     color[3] = SGMiscf::max(0, SGMiscf::min(1, color[3] + alphaOff));
 323     colors->push_back(toOsg(color));
 324   }
 325
 326   osg::Geometry* geometry = new osg::Geometry;
 327
 328   geometry->setVertexArray(vertices);
 329   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 330   geometry->setColorArray(colors);
 331   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 332
 333   osg::DrawArrays* drawArrays;
 334   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::POINTS,
 335                                    0, vertices->size());
 336   geometry->addPrimitiveSet(drawArrays);
 337
 338   {
 339     ScopedLock<Mutex> lock(lightMutex);
 340     if (!simpleLightSS.valid()) {
 341       StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 342       simpleLightSS = new StateSet;
 343       simpleLightSS->setRenderBinDetails(POINT_LIGHTS_BIN, "DepthSortedBin");
 344       simpleLightSS->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 345       simpleLightSS->setAttributeAndModes(attrFact->getStandardBlendFunc());
 346       simpleLightSS->setAttributeAndModes(attrFact->getStandardAlphaFunc());
 347     }
 348   }
 349   geometry->setStateSet(simpleLightSS.get());
 350   return geometry;
 351 }
 352
 353
 354 osg::Drawable*
 355 SGLightFactory::getLights(const SGDirectionalLightBin& lights)
 356 {
 357   if (lights.getNumLights() <= 0)
 358     return 0;
 359
 360   osg::Vec3Array* vertices = new osg::Vec3Array;
 361   osg::Vec4Array* colors = new osg::Vec4Array;
 362
 363   for (unsigned i = 0; i < lights.getNumLights(); ++i) {
 364     SGVec4f visibleColor(lights.getLight(i).color);
 365     SGVec4f invisibleColor(visibleColor[0], visibleColor[1],
 366                            visibleColor[2], 0);
 367     SGVec3f normal = normalize(lights.getLight(i).normal);
 368     SGVec3f perp1 = perpendicular(normal);
 369     SGVec3f perp2 = cross(normal, perp1);
 370     SGVec3f position = lights.getLight(i).position;
 371     vertices->push_back(toOsg(position));
 372     vertices->push_back(toOsg(position + perp1));
 373     vertices->push_back(toOsg(position + perp2));
 374     colors->push_back(toOsg(visibleColor));
 375     colors->push_back(toOsg(invisibleColor));
 376     colors->push_back(toOsg(invisibleColor));
 377   }
 378
 379   osg::Geometry* geometry = new osg::Geometry;
 380
 381   geometry->setVertexArray(vertices);
 382   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 383   geometry->setColorArray(colors);
 384   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 385
 386   osg::DrawArrays* drawArrays;
 387   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES,
 388                                    0, vertices->size());
 389   geometry->addPrimitiveSet(drawArrays);
 390   return geometry;
 391 }
 392
 393 static SGVasiDrawable*
 394 buildVasi(const SGDirectionalLightBin& lights, const SGVec3f& up,
 395        const SGVec4f& red, const SGVec4f& white)
 396 {
 397   unsigned count = lights.getNumLights();
 398   if ( count == 4 ) {
 399     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 400
 401     // PAPI configuration
 402     // papi D
 403     drawable->addLight(lights.getLight(0).position,
 404                        lights.getLight(0).normal, up, 3.5);
 405     // papi C
 406     drawable->addLight(lights.getLight(1).position,
 407                        lights.getLight(1).normal, up, 3.167);
 408     // papi B
 409     drawable->addLight(lights.getLight(2).position,
 410                        lights.getLight(2).normal, up, 2.833);
 411     // papi A
 412     drawable->addLight(lights.getLight(3).position,
 413                        lights.getLight(3).normal, up, 2.5);
 414     return drawable;
 415
 416   } else if (count == 6) {
 417     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 418
 419     // probably vasi, first 3 are downwind bar (2.5 deg)
 420     for (unsigned i = 0; i < 3; ++i)
 421       drawable->addLight(lights.getLight(i).position,
 422                          lights.getLight(i).normal, up, 2.5);
 423     // last 3 are upwind bar (3.0 deg)
 424     for (unsigned i = 3; i < 6; ++i)
 425       drawable->addLight(lights.getLight(i).position,
 426                          lights.getLight(i).normal, up, 3.0);
 427     return drawable;
 428
 429   } else if (count == 12) {
 430     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 431
 432     // probably vasi, first 6 are downwind bar (2.5 deg)
 433     for (unsigned i = 0; i < 6; ++i)
 434       drawable->addLight(lights.getLight(i).position,
 435                          lights.getLight(i).normal, up, 2.5);
 436     // last 6 are upwind bar (3.0 deg)
 437     for (unsigned i = 6; i < 12; ++i)
 438       drawable->addLight(lights.getLight(i).position,
 439                          lights.getLight(i).normal, up, 3.0);
 440     return drawable;
 441
 442   } else {
 443     // fail safe
 444     SG_LOG(SG_TERRAIN, SG_ALERT,
 445            "unknown vasi/papi configuration, count = " << count);
 446     return 0;
 447   }
 448 }
 449
 450 osg::Drawable*
 451 SGLightFactory::getVasi(const SGVec3f& up, const SGDirectionalLightBin& lights,
 452                         const SGVec4f& red, const SGVec4f& white)
 453 {
 454   SGVasiDrawable* drawable = buildVasi(lights, up, red, white);
 455   if (!drawable)
 456     return 0;
 457
 458   osg::StateSet* stateSet = drawable->getOrCreateStateSet();
 459   stateSet->setRenderBinDetails(POINT_LIGHTS_BIN, "DepthSortedBin");
 460   stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 461
 462   osg::BlendFunc* blendFunc = new osg::BlendFunc;
 463   stateSet->setAttribute(blendFunc);
 464   stateSet->setMode(GL_BLEND, osg::StateAttribute::ON);
 465
 466   osg::AlphaFunc* alphaFunc;
 467   alphaFunc = new osg::AlphaFunc(osg::AlphaFunc::GREATER, 0.01);
 468   stateSet->setAttribute(alphaFunc);
 469   stateSet->setMode(GL_ALPHA_TEST, osg::StateAttribute::ON);
 470
 471   return drawable;
 472 }
 473
 474 osg::Node*
 475 SGLightFactory::getSequenced(const SGDirectionalLightBin& lights)
 476 {
 477   if (lights.getNumLights() <= 0)
 478     return 0;
 479
 480   // generate a repeatable random seed
 481   sg_srandom(unsigned(lights.getLight(0).position[0]));
 482   float flashTime = 2e-2 + 5e-3*sg_random();
 483   osg::Sequence* sequence = new osg::Sequence;
 484   sequence->setDefaultTime(flashTime);
 485   Effect* effect = getLightEffect(10.0f, osg::Vec3(1.0, 0.0001, 0.00000001),
 486                                   6.0f, 10.0f, true);
 487   for (int i = lights.getNumLights() - 1; 0 <= i; --i) {
 488     EffectGeode* egeode = new EffectGeode;
 489     egeode->setEffect(effect);
 490     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 491     sequence->addChild(egeode, flashTime);
 492   }
 493   sequence->addChild(new osg::Group, 1 + 1e-1*sg_random());
 494   sequence->setInterval(osg::Sequence::LOOP, 0, -1);
 495   sequence->setDuration(1.0f, -1);
 496   sequence->setMode(osg::Sequence::START);
 497   sequence->setSync(true);
 498   return sequence;
 499 }
 500
 501 osg::Node*
 502 SGLightFactory::getOdal(const SGLightBin& lights)
 503 {
 504   if (lights.getNumLights() < 2)
 505     return 0;
 506
 507   // generate a repeatable random seed
 508   sg_srandom(unsigned(lights.getLight(0).position[0]));
 509   float flashTime = 2e-2 + 5e-3*sg_random();
 510   osg::Sequence* sequence = new osg::Sequence;
 511   sequence->setDefaultTime(flashTime);
 512   Effect* effect = getLightEffect(10.0f, osg::Vec3(1.0, 0.0001, 0.00000001),
 513                                   6.0, 10.0, false);
 514   // centerline lights
 515   for (int i = lights.getNumLights() - 1; 2 <= i; --i) {
 516     EffectGeode* egeode = new EffectGeode;
 517     egeode->setEffect(effect);
 518     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 519     sequence->addChild(egeode, flashTime);
 520   }
 521   // runway end lights
 522   osg::Group* group = new osg::Group;
 523   for (unsigned i = 0; i < 2; ++i) {
 524     EffectGeode* egeode = new EffectGeode;
 525     egeode->setEffect(effect);
 526     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 527     group->addChild(egeode);
 528   }
 529   sequence->addChild(group, flashTime);
 530
 531   // add an extra empty group for a break
 532   sequence->addChild(new osg::Group, 9 + 1e-1*sg_random());
 533   sequence->setInterval(osg::Sequence::LOOP, 0, -1);
 534   sequence->setDuration(1.0f, -1);
 535   sequence->setMode(osg::Sequence::START);
 536   sequence->setSync(true);
 537
 538   return sequence;
 539 }