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, ref_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         return eitr->second.get();
 179     // Basic stuff; no sprite or attenuation support
 180     Pass *basicPass = new Pass;
 181     basicPass->setRenderBinDetails(POINT_LIGHTS_BIN, "RenderBin");
 182     basicPass->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 183     StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 184     basicPass->setAttributeAndModes(attrFact->getStandardBlendFunc());
 185     basicPass->setAttributeAndModes(attrFact->getStandardAlphaFunc());
 186     if (directional) {
 187         basicPass->setAttributeAndModes(attrFact->getCullFaceBack());
 188         basicPass->setAttribute(polyMode.get());
 189     }
 190     Pass *attenuationPass = clone(basicPass, CopyOp::SHALLOW_COPY);
 191     osg::Point* point = new osg::Point;
 192     point->setMinSize(minSize);
 193     point->setMaxSize(maxSize);
 194     point->setSize(size);
 195     point->setDistanceAttenuation(attenuation);
 196     attenuationPass->setAttributeAndModes(point);
 197     Pass *spritePass = clone(basicPass, CopyOp::SHALLOW_COPY);
 198     spritePass->setTextureAttributeAndModes(0, pointSprite.get(),
 199                                             osg::StateAttribute::ON);
 200     Texture2D* texture = gen_standard_light_sprite();
 201     spritePass->setTextureAttribute(0, texture);
 202     spritePass->setTextureMode(0, GL_TEXTURE_2D,
 203                                osg::StateAttribute::ON);
 204     spritePass->setTextureAttribute(0, attrFact->getStandardTexEnv());
 205     Pass *combinedPass = clone(spritePass, CopyOp::SHALLOW_COPY);
 206     combinedPass->setAttributeAndModes(point);
 207     Effect* effect = new Effect;
 208     std::vector<std::string> parameterExtensions;
 209
 210     if (SGSceneFeatures::instance()->getEnablePointSpriteLights())
 211     {
 212         std::vector<std::string> combinedExtensions;
 213         combinedExtensions.push_back("GL_ARB_point_sprite");
 214         combinedExtensions.push_back("GL_ARB_point_parameters");
 215         Technique* combinedTniq = new Technique;
 216         combinedTniq->passes.push_back(combinedPass);
 217         combinedTniq->setGLExtensionsPred(2.0, combinedExtensions);
 218         effect->techniques.push_back(combinedTniq);
 219         std::vector<std::string> spriteExtensions;
 220         spriteExtensions.push_back(combinedExtensions.front());
 221         Technique* spriteTniq = new Technique;
 222         spriteTniq->passes.push_back(spritePass);
 223         spriteTniq->setGLExtensionsPred(2.0, spriteExtensions);
 224         effect->techniques.push_back(spriteTniq);
 225         parameterExtensions.push_back(combinedExtensions.back());
 226     }
 227
 228     Technique* parameterTniq = new Technique;
 229     parameterTniq->passes.push_back(attenuationPass);
 230     parameterTniq->setGLExtensionsPred(1.4, parameterExtensions);
 231     effect->techniques.push_back(parameterTniq);
 232     Technique* basicTniq = new Technique(true);
 233     basicTniq->passes.push_back(basicPass);
 234     effect->techniques.push_back(basicTniq);
 235     effectMap.insert(std::make_pair(pointParams, effect));
 236     return effect;
 237 }
 238
 239
 240 osg::Drawable*
 241 SGLightFactory::getLightDrawable(const SGLightBin::Light& light)
 242 {
 243   osg::Vec3Array* vertices = new osg::Vec3Array;
 244   osg::Vec4Array* colors = new osg::Vec4Array;
 245
 246   vertices->push_back(toOsg(light.position));
 247   colors->push_back(toOsg(light.color));
 248
 249   osg::Geometry* geometry = new osg::Geometry;
 250   geometry->setVertexArray(vertices);
 251   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 252   geometry->setColorArray(colors);
 253   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 254
 255   // Enlarge the bounding box to avoid such light nodes being victim to
 256   // small feature culling.
 257   geometry->setComputeBoundingBoxCallback(new SGEnlargeBoundingBox(1));
 258
 259   osg::DrawArrays* drawArrays;
 260   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::POINTS,
 261                                    0, vertices->size());
 262   geometry->addPrimitiveSet(drawArrays);
 263   return geometry;
 264 }
 265
 266 osg::Drawable*
 267 SGLightFactory::getLightDrawable(const SGDirectionalLightBin::Light& light)
 268 {
 269   osg::Vec3Array* vertices = new osg::Vec3Array;
 270   osg::Vec4Array* colors = new osg::Vec4Array;
 271
 272   SGVec4f visibleColor(light.color);
 273   SGVec4f invisibleColor(visibleColor[0], visibleColor[1],
 274                          visibleColor[2], 0);
 275   SGVec3f normal = normalize(light.normal);
 276   SGVec3f perp1 = perpendicular(normal);
 277   SGVec3f perp2 = cross(normal, perp1);
 278   SGVec3f position = light.position;
 279   vertices->push_back(toOsg(position));
 280   vertices->push_back(toOsg(position + perp1));
 281   vertices->push_back(toOsg(position + perp2));
 282   colors->push_back(toOsg(visibleColor));
 283   colors->push_back(toOsg(invisibleColor));
 284   colors->push_back(toOsg(invisibleColor));
 285
 286   osg::Geometry* geometry = new osg::Geometry;
 287   geometry->setVertexArray(vertices);
 288   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 289   geometry->setColorArray(colors);
 290   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 291   // Enlarge the bounding box to avoid such light nodes being victim to
 292   // small feature culling.
 293   geometry->setComputeBoundingBoxCallback(new SGEnlargeBoundingBox(1));
 294
 295   osg::DrawArrays* drawArrays;
 296   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES,
 297                                    0, vertices->size());
 298   geometry->addPrimitiveSet(drawArrays);
 299   return geometry;
 300 }
 301
 302 namespace
 303 {
 304   ref_ptr<StateSet> simpleLightSS;
 305 }
 306 osg::Drawable*
 307 SGLightFactory::getLights(const SGLightBin& lights, unsigned inc, float alphaOff)
 308 {
 309   if (lights.getNumLights() <= 0)
 310     return 0;
 311
 312   osg::Vec3Array* vertices = new osg::Vec3Array;
 313   osg::Vec4Array* colors = new osg::Vec4Array;
 314
 315   for (unsigned i = 0; i < lights.getNumLights(); i += inc) {
 316     vertices->push_back(toOsg(lights.getLight(i).position));
 317     SGVec4f color = lights.getLight(i).color;
 318     color[3] = SGMiscf::max(0, SGMiscf::min(1, color[3] + alphaOff));
 319     colors->push_back(toOsg(color));
 320   }
 321
 322   osg::Geometry* geometry = new osg::Geometry;
 323
 324   geometry->setVertexArray(vertices);
 325   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 326   geometry->setColorArray(colors);
 327   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 328
 329   osg::DrawArrays* drawArrays;
 330   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::POINTS,
 331                                    0, vertices->size());
 332   geometry->addPrimitiveSet(drawArrays);
 333
 334   {
 335     ScopedLock<Mutex> lock(lightMutex);
 336     if (!simpleLightSS.valid()) {
 337       StateAttributeFactory *attrFact = StateAttributeFactory::instance();
 338       simpleLightSS = new StateSet;
 339       simpleLightSS->setRenderBinDetails(POINT_LIGHTS_BIN, "RenderBin");
 340       simpleLightSS->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 341       simpleLightSS->setAttributeAndModes(attrFact->getStandardBlendFunc());
 342       simpleLightSS->setAttributeAndModes(attrFact->getStandardAlphaFunc());
 343     }
 344   }
 345   geometry->setStateSet(simpleLightSS.get());
 346   return geometry;
 347 }
 348
 349
 350 osg::Drawable*
 351 SGLightFactory::getLights(const SGDirectionalLightBin& lights)
 352 {
 353   if (lights.getNumLights() <= 0)
 354     return 0;
 355
 356   osg::Vec3Array* vertices = new osg::Vec3Array;
 357   osg::Vec4Array* colors = new osg::Vec4Array;
 358
 359   for (unsigned i = 0; i < lights.getNumLights(); ++i) {
 360     SGVec4f visibleColor(lights.getLight(i).color);
 361     SGVec4f invisibleColor(visibleColor[0], visibleColor[1],
 362                            visibleColor[2], 0);
 363     SGVec3f normal = normalize(lights.getLight(i).normal);
 364     SGVec3f perp1 = perpendicular(normal);
 365     SGVec3f perp2 = cross(normal, perp1);
 366     SGVec3f position = lights.getLight(i).position;
 367     vertices->push_back(toOsg(position));
 368     vertices->push_back(toOsg(position + perp1));
 369     vertices->push_back(toOsg(position + perp2));
 370     colors->push_back(toOsg(visibleColor));
 371     colors->push_back(toOsg(invisibleColor));
 372     colors->push_back(toOsg(invisibleColor));
 373   }
 374
 375   osg::Geometry* geometry = new osg::Geometry;
 376
 377   geometry->setVertexArray(vertices);
 378   geometry->setNormalBinding(osg::Geometry::BIND_OFF);
 379   geometry->setColorArray(colors);
 380   geometry->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
 381
 382   osg::DrawArrays* drawArrays;
 383   drawArrays = new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES,
 384                                    0, vertices->size());
 385   geometry->addPrimitiveSet(drawArrays);
 386   return geometry;
 387 }
 388
 389 static SGVasiDrawable*
 390 buildVasi(const SGDirectionalLightBin& lights, const SGVec3f& up,
 391        const SGVec4f& red, const SGVec4f& white)
 392 {
 393   unsigned count = lights.getNumLights();
 394   if ( count == 4 ) {
 395     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 396
 397     // PAPI configuration
 398     // papi D
 399     drawable->addLight(lights.getLight(0).position,
 400                        lights.getLight(0).normal, up, 3.5);
 401     // papi C
 402     drawable->addLight(lights.getLight(1).position,
 403                        lights.getLight(1).normal, up, 3.167);
 404     // papi B
 405     drawable->addLight(lights.getLight(2).position,
 406                        lights.getLight(2).normal, up, 2.833);
 407     // papi A
 408     drawable->addLight(lights.getLight(3).position,
 409                        lights.getLight(3).normal, up, 2.5);
 410     return drawable;
 411
 412   } else if (count == 6) {
 413     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 414
 415     // probably vasi, first 3 are downwind bar (2.5 deg)
 416     for (unsigned i = 0; i < 3; ++i)
 417       drawable->addLight(lights.getLight(i).position,
 418                          lights.getLight(i).normal, up, 2.5);
 419     // last 3 are upwind bar (3.0 deg)
 420     for (unsigned i = 3; i < 6; ++i)
 421       drawable->addLight(lights.getLight(i).position,
 422                          lights.getLight(i).normal, up, 3.0);
 423     return drawable;
 424
 425   } else if (count == 12) {
 426     SGVasiDrawable* drawable = new SGVasiDrawable(red, white);
 427
 428     // probably vasi, first 6 are downwind bar (2.5 deg)
 429     for (unsigned i = 0; i < 6; ++i)
 430       drawable->addLight(lights.getLight(i).position,
 431                          lights.getLight(i).normal, up, 2.5);
 432     // last 6 are upwind bar (3.0 deg)
 433     for (unsigned i = 6; i < 12; ++i)
 434       drawable->addLight(lights.getLight(i).position,
 435                          lights.getLight(i).normal, up, 3.0);
 436     return drawable;
 437
 438   } else {
 439     // fail safe
 440     SG_LOG(SG_TERRAIN, SG_ALERT,
 441            "unknown vasi/papi configuration, count = " << count);
 442     return 0;
 443   }
 444 }
 445
 446 osg::Drawable*
 447 SGLightFactory::getVasi(const SGVec3f& up, const SGDirectionalLightBin& lights,
 448                         const SGVec4f& red, const SGVec4f& white)
 449 {
 450   SGVasiDrawable* drawable = buildVasi(lights, up, red, white);
 451   if (!drawable)
 452     return 0;
 453
 454   osg::StateSet* stateSet = drawable->getOrCreateStateSet();
 455   stateSet->setRenderBinDetails(POINT_LIGHTS_BIN, "RenderBin");
 456   stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 457
 458   osg::BlendFunc* blendFunc = new osg::BlendFunc;
 459   stateSet->setAttribute(blendFunc);
 460   stateSet->setMode(GL_BLEND, osg::StateAttribute::ON);
 461
 462   osg::AlphaFunc* alphaFunc;
 463   alphaFunc = new osg::AlphaFunc(osg::AlphaFunc::GREATER, 0.01);
 464   stateSet->setAttribute(alphaFunc);
 465   stateSet->setMode(GL_ALPHA_TEST, osg::StateAttribute::ON);
 466
 467   return drawable;
 468 }
 469
 470 osg::Node*
 471 SGLightFactory::getSequenced(const SGDirectionalLightBin& lights)
 472 {
 473   if (lights.getNumLights() <= 0)
 474     return 0;
 475
 476   // generate a repeatable random seed
 477   sg_srandom(unsigned(lights.getLight(0).position[0]));
 478   float flashTime = 2e-2 + 5e-3*sg_random();
 479   osg::Sequence* sequence = new osg::Sequence;
 480   sequence->setDefaultTime(flashTime);
 481   Effect* effect = getLightEffect(10.0f, osg::Vec3(1.0, 0.0001, 0.00000001),
 482                                   6.0f, 10.0f, true);
 483   for (int i = lights.getNumLights() - 1; 0 <= i; --i) {
 484     EffectGeode* egeode = new EffectGeode;
 485     egeode->setEffect(effect);
 486     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 487     sequence->addChild(egeode, flashTime);
 488   }
 489   sequence->addChild(new osg::Group, 1 + 1e-1*sg_random());
 490   sequence->setInterval(osg::Sequence::LOOP, 0, -1);
 491   sequence->setDuration(1.0f, -1);
 492   sequence->setMode(osg::Sequence::START);
 493   sequence->setSync(true);
 494   return sequence;
 495 }
 496
 497 osg::Node*
 498 SGLightFactory::getOdal(const SGLightBin& lights)
 499 {
 500   if (lights.getNumLights() < 2)
 501     return 0;
 502
 503   // generate a repeatable random seed
 504   sg_srandom(unsigned(lights.getLight(0).position[0]));
 505   float flashTime = 2e-2 + 5e-3*sg_random();
 506   osg::Sequence* sequence = new osg::Sequence;
 507   sequence->setDefaultTime(flashTime);
 508   Effect* effect = getLightEffect(10.0f, osg::Vec3(1.0, 0.0001, 0.00000001),
 509                                   6.0, 10.0, false);
 510   // centerline lights
 511   for (int i = lights.getNumLights() - 1; 2 <= i; --i) {
 512     EffectGeode* egeode = new EffectGeode;
 513     egeode->setEffect(effect);
 514     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 515     sequence->addChild(egeode, flashTime);
 516   }
 517   // runway end lights
 518   osg::Group* group = new osg::Group;
 519   for (unsigned i = 0; i < 2; ++i) {
 520     EffectGeode* egeode = new EffectGeode;
 521     egeode->setEffect(effect);
 522     egeode->addDrawable(getLightDrawable(lights.getLight(i)));
 523     group->addChild(egeode);
 524   }
 525   sequence->addChild(group, flashTime);
 526
 527   // add an extra empty group for a break
 528   sequence->addChild(new osg::Group, 9 + 1e-1*sg_random());
 529   sequence->setInterval(osg::Sequence::LOOP, 0, -1);
 530   sequence->setDuration(1.0f, -1);
 531   sequence->setMode(osg::Sequence::START);
 532   sequence->setSync(true);
 533
 534   return sequence;
 535 }