Files
OpenSceneGraph/src/Demos/osgshadowtexture/osgshadowtexture.cpp

516 lines
15 KiB
C++

#include <osg/Notify>
#include <osg/MatrixTransform>
#include <osg/ShapeDrawable>
#include <osg/PositionAttitudeTransform>
#include <osg/Geometry>
#include <osg/Texture2D>
#include <osg/TexGen>
#include <osg/Material>
#include <osg/LightSource>
#include <osgUtil/Optimizer>
#include <osgUtil/RenderToTextureStage>
#include <osgDB/Registry>
#include <osgDB/ReadFile>
#include <osgGA/TrackballManipulator>
#include <osgGA/FlightManipulator>
#include <osgGA/DriveManipulator>
#include <osgGLUT/glut>
#include <osgGLUT/Viewer>
// for the grid data..
#include "../osghangglide/terrain_coords.h"
class MyTexGen : public osg::TexGen
{
public:
void setMatrix(const osg::Matrix& matrix)
{
_matrix = matrix;
}
virtual void apply(osg::State& state) const
{
glPushMatrix();
glLoadMatrixf(_matrix.ptr());
TexGen::apply(state);
glPopMatrix();
}
osg::Matrix _matrix;
};
class MyCullCallback : public osg::NodeCallback
{
public:
MyCullCallback(osg::Node* subgraph,osg::Texture2D* texture,const osg::Vec3& position):
_subgraph(subgraph),
_texture(texture),
_position(position) {}
virtual void operator()(osg::Node* node, osg::NodeVisitor* nv)
{
osgUtil::CullVisitor* cullVisitor = dynamic_cast<osgUtil::CullVisitor*>(nv);
if (cullVisitor && (_texture.valid() && _subgraph.valid()))
{
doPreRender(*node,*cullVisitor);
}
else
{
// must traverse the subgraph
traverse(node,nv);
}
}
void doPreRender(osg::Node& node, osgUtil::CullVisitor& cv);
osg::ref_ptr<osg::Node> _subgraph;
osg::ref_ptr<osg::Texture2D> _texture;
osg::Vec3 _position;
};
void MyCullCallback::doPreRender(osg::Node& node, osgUtil::CullVisitor& cv)
{
const osg::BoundingSphere& bs = _subgraph->getBound();
if (!bs.valid())
{
osg::notify(osg::WARN) << "bb invalid"<<_subgraph.get()<<std::endl;
return;
}
// create the render to texture stage.
osg::ref_ptr<osgUtil::RenderToTextureStage> rtts = osgNew osgUtil::RenderToTextureStage;
// set up lighting.
// currently ignore lights in the scene graph itself..
// will do later.
osgUtil::RenderStage* previous_stage = cv.getCurrentRenderBin()->_stage;
// set up the background color and clear mask.
rtts->setClearColor(osg::Vec4(1.0f,1.0f,1.0f,0.0f));
rtts->setClearMask(previous_stage->getClearMask());
// set up to charge the same RenderStageLighting is the parent previous stage.
rtts->setRenderStageLighting(previous_stage->getRenderStageLighting());
// record the render bin, to be restored after creation
// of the render to text
osgUtil::RenderBin* previousRenderBin = cv.getCurrentRenderBin();
// set the current renderbin to be the newly created stage.
cv.setCurrentRenderBin(rtts.get());
float centerDistance = (_position-bs.center()).length();
float znear = centerDistance+bs.radius();
float zfar = centerDistance-bs.radius();
float zNearRatio = 0.001f;
if (znear<zfar*zNearRatio) znear = zfar*zNearRatio;
// 2:1 aspect ratio as per flag geomtry below.
float top = (bs.radius()/centerDistance)*znear;
float right = top;
// set up projection.
osg::Matrix* projection = osgNew osg::Matrix;
projection->makeFrustum(-right,right,-top,top,znear,zfar);
cv.pushProjectionMatrix(projection);
osg::Matrix* matrix = new osg::Matrix;
matrix->makeLookAt(_position,bs.center(),osg::Vec3(0.0f,1.0f,0.0f));
osg::Matrix MV = cv.getModelViewMatrix();
// compute the matrix which takes a vertex from local coords into tex coords
// will use this later to specify osg::TexGen..
osg::Matrix MVPT =
*matrix *
*projection *
osg::Matrix::translate(1.0,1.0,1.0) *
osg::Matrix::scale(0.5f,0.5f,0.5f);
cv.pushModelViewMatrix(matrix);
osg::ref_ptr<osg::StateSet> shadowState = osgNew osg::StateSet;
// make the material black for a shadow.
osg::Material* material = new osg::Material;
material->setAmbient(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f));
material->setDiffuse(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f));
material->setEmission(osg::Material::FRONT_AND_BACK,osg::Vec4(0.0f,0.0f,0.0f,1.0f));
material->setShininess(osg::Material::FRONT_AND_BACK,0.0f);
shadowState->setAttribute(material,osg::StateAttribute::OVERRIDE);
cv.pushStateSet(shadowState.get());
{
// traverse the subgraph
_subgraph->accept(cv);
}
cv.popStateSet();
// restore the previous model view matrix.
cv.popModelViewMatrix();
// restore the previous model view matrix.
cv.popProjectionMatrix();
// restore the previous renderbin.
cv.setCurrentRenderBin(previousRenderBin);
if (rtts->_renderGraphList.size()==0 && rtts->_bins.size()==0)
{
// getting to this point means that all the subgraph has been
// culled by small feature culling or is beyond LOD ranges.
return;
}
int height = 256;
int width = 256;
const osg::Viewport& viewport = *cv.getViewport();
// offset the impostor viewport from the center of the main window
// viewport as often the edges of the viewport might be obscured by
// other windows, which can cause image/reading writing problems.
int center_x = viewport.x()+viewport.width()/2;
int center_y = viewport.y()+viewport.height()/2;
osg::Viewport* new_viewport = new osg::Viewport;
new_viewport->setViewport(center_x-width/2,center_y-height/2,width,height);
rtts->setViewport(new_viewport);
shadowState->setAttribute(new_viewport);
// and the render to texture stage to the current stages
// dependancy list.
cv.getCurrentRenderBin()->_stage->addToDependencyList(rtts.get());
// if one exist attach texture to the RenderToTextureStage.
if (_texture.valid()) rtts->setTexture(_texture.get());
// set up the stateset to decorate the subgraph with the shadow texture
// with the appropriate tex gen coords.
osg::StateSet* stateset = new osg::StateSet;
osg::Plane plane_s(MVPT(0,0),MVPT(1,0),MVPT(2,0),MVPT(3,0));
osg::Plane plane_t(MVPT(0,1),MVPT(1,1),MVPT(2,1),MVPT(3,1));
osg::Plane plane_r(MVPT(0,2),MVPT(1,2),MVPT(2,2),MVPT(3,2));
osg::Plane plane_q(MVPT(0,3),MVPT(1,3),MVPT(2,3),MVPT(3,3));
// plane_s.makeUnitLength();
// plane_t.makeUnitLength();
// plane_r.makeUnitLength();
// plane_q.makeUnitLength();
// plane_s.set(inverseMV*plane_s.asVec4());
// plane_t.set(inverseMV*plane_t.asVec4());
// plane_r.set(inverseMV*plane_r.asVec4());
// plane_q.set(inverseMV*plane_q.asVec4());
// plane_s.transformProvidingInverse(inverseMV);
// plane_t.transformProvidingInverse(inverseMV);
// plane_r.transformProvidingInverse(inverseMV);
// plane_q.transformProvidingInverse(inverseMV);
MyTexGen* texgen = new MyTexGen;
texgen->setMatrix(MV);
texgen->setMode(osg::TexGen::EYE_LINEAR);
texgen->setPlane(osg::TexGen::S,plane_s);
texgen->setPlane(osg::TexGen::T,plane_t);
texgen->setPlane(osg::TexGen::R,plane_r);
texgen->setPlane(osg::TexGen::Q,plane_q);
int _unit = 1;
stateset->setTextureAttributeAndModes(_unit,_texture.get(),osg::StateAttribute::ON);
stateset->setTextureAttribute(_unit,texgen);
stateset->setTextureMode(_unit,GL_TEXTURE_GEN_S,osg::StateAttribute::ON);
stateset->setTextureMode(_unit,GL_TEXTURE_GEN_T,osg::StateAttribute::ON);
stateset->setTextureMode(_unit,GL_TEXTURE_GEN_R,osg::StateAttribute::ON);
stateset->setTextureMode(_unit,GL_TEXTURE_GEN_Q,osg::StateAttribute::ON);
cv.pushStateSet(stateset);
// must traverse the subgraph
traverse(&node,&cv);
cv.popStateSet();
}
osg::AnimationPath* createAnimationPath(const osg::Vec3& center,float radius,double looptime)
{
// set up the animation path
osg::AnimationPath* animationPath = new osg::AnimationPath;
animationPath->setLoopMode(osg::AnimationPath::LOOP);
int numSamples = 40;
float yaw = 0.0f;
float yaw_delta = 2.0f*osg::PI/((float)numSamples-1.0f);
float roll = osg::inDegrees(30.0f);
double time=0.0f;
double time_delta = looptime/(double)numSamples;
for(int i=0;i<numSamples;++i)
{
osg::Vec3 position(center+osg::Vec3(sinf(yaw)*radius,cosf(yaw)*radius,0.0f));
osg::Quat rotation(osg::Quat(roll,osg::Vec3(0.0,1.0,0.0))*osg::Quat(-(yaw+osg::inDegrees(90.0f)),osg::Vec3(0.0,0.0,1.0)));
animationPath->insert(time,osg::AnimationPath::ControlPoint(position,rotation));
yaw += yaw_delta;
time += time_delta;
}
return animationPath;
}
osg::Node* createBase(const osg::Vec3& center,float radius)
{
osg::Geode* geode = osgNew osg::Geode;
// set up the texture of the base.
osg::StateSet* stateset = osgNew osg::StateSet();
osg::Image* image = osgDB::readImageFile("Images/lz.rgb");
if (image)
{
osg::Texture2D* texture = osgNew osg::Texture2D;
texture->setImage(image);
stateset->setTextureAttributeAndModes(0,texture,osg::StateAttribute::ON);
}
geode->setStateSet( stateset );
osg::Grid* grid = new osg::Grid;
grid->allocateGrid(38,39);
grid->setOrigin(center+osg::Vec3(-radius,-radius,0.0f));
grid->setXInterval(radius*2.0f/(float)(38-1));
grid->setYInterval(radius*2.0f/(float)(39-1));
float minHeight = FLT_MAX;
float maxHeight = -FLT_MAX;
unsigned int r;
for(r=0;r<39;++r)
{
for(unsigned int c=0;c<38;++c)
{
float h = vertex[r+c*39][2];
if (h>maxHeight) maxHeight=h;
if (h<minHeight) minHeight=h;
}
}
float hieghtScale = radius*0.5f/(maxHeight-minHeight);
float hieghtOffset = -(minHeight+maxHeight)*0.5f;
for(r=0;r<39;++r)
{
for(unsigned int c=0;c<38;++c)
{
float h = vertex[r+c*39][2];
grid->setHeight(c,r,(h+hieghtOffset)*hieghtScale);
}
}
geode->addDrawable(new osg::ShapeDrawable(grid));
osg::Group* group = osgNew osg::Group;
group->addChild(geode);
return group;
}
osg::Node* createMovingModel(const osg::Vec3& center, float radius)
{
float animationLength = 10.0f;
osg::AnimationPath* animationPath = createAnimationPath(center,radius,animationLength);
osg::Group* model = new osg::Group;
// osg::Node* glider = osgDB::readNodeFile("glider.osg");
// if (glider)
// {
// const osg::BoundingSphere& bs = glider->getBound();
//
// float size = radius/bs.radius()*0.3f;
// osg::MatrixTransform* positioned = osgNew osg::MatrixTransform;
// positioned->setDataVariance(osg::Object::STATIC);
// positioned->setMatrix(osg::Matrix::translate(-bs.center())*
// osg::Matrix::scale(size,size,size)*
// osg::Matrix::rotate(osg::inDegrees(-90.0f),0.0f,0.0f,1.0f));
//
// positioned->addChild(glider);
//
// osg::PositionAttitudeTransform* xform = osgNew osg::PositionAttitudeTransform;
// xform->setAppCallback(new osg::PositionAttitudeTransform::AnimationPathCallback(animationPath,0.0,1.0));
// xform->addChild(positioned);
//
// model->addChild(xform);
// }
osg::Node* cessna = osgDB::readNodeFile("cessna.osg");
if (cessna)
{
const osg::BoundingSphere& bs = cessna->getBound();
float size = radius/bs.radius()*0.3f;
osg::MatrixTransform* positioned = osgNew osg::MatrixTransform;
positioned->setDataVariance(osg::Object::STATIC);
positioned->setMatrix(osg::Matrix::translate(-bs.center())*
osg::Matrix::scale(size,size,size)*
osg::Matrix::rotate(osg::inDegrees(180.0f),0.0f,0.0f,2.0f));
positioned->addChild(cessna);
osg::MatrixTransform* xform = osgNew osg::MatrixTransform;
xform->setAppCallback(new osg::MatrixTransform::AnimationPathCallback(animationPath,0.0f,2.0));
xform->addChild(positioned);
model->addChild(xform);
}
return model;
}
osg::Node* createModel()
{
osg::Vec3 center(0.0f,0.0f,0.0f);
float radius = 100.0f;
osg::Group* root = osgNew osg::Group;
// the occluder subgraph
osg::Node* occluder = createMovingModel(center,radius*0.5f);
// the occludee subgraph
osg::Node* occludee = createBase(center-osg::Vec3(0.0f,0.0f,radius*0.25),radius);
// now add a state with a texture for the shadow
osg::Texture2D* texture = new osg::Texture2D;
texture->setFilter(osg::Texture2D::MIN_FILTER,osg::Texture2D::LINEAR);
texture->setFilter(osg::Texture2D::MAG_FILTER,osg::Texture2D::LINEAR);
osg::Vec3 lightPosition(center+osg::Vec3(0.0f,0.0f,radius));
osg::Geode* lightgeode = new osg::Geode;
lightgeode->addDrawable(new osg::ShapeDrawable(new osg::Sphere(lightPosition,radius/100.0f)));
osg::Light* light = new osg::Light;
light->setPosition(osg::Vec4(lightPosition,1.0f));
light->setLightNum(0);
osg::LightSource* lightsource = new osg::LightSource;
lightsource->setLight(light);
occludee->setCullCallback(new MyCullCallback(occluder,texture,lightPosition));
root->addChild(lightgeode);
root->addChild(lightsource);
root->addChild(occluder);
root->addChild(occludee);
return root;
}
int main( int argc, char **argv )
{
// initialize the GLUT
glutInit( &argc, argv );
// create the commandline args.
std::vector<std::string> commandLine;
for(int i=1;i<argc;++i) commandLine.push_back(argv[i]);
// initialize the viewer.
osgGLUT::Viewer viewer;
viewer.setWindowTitle(argv[0]);
// configure the viewer from the commandline arguments, and eat any
// parameters that have been matched.
viewer.readCommandLine(commandLine);
// configure the plugin registry from the commandline arguments, and
// eat any parameters that have been matched.
osgDB::readCommandLine(commandLine);
// load the nodes from the commandline arguments.
osg::Node* model = createModel();
if (!model)
{
return 1;
}
// tilt the scene so the default eye position is looking down on the model.
osg::MatrixTransform* rootnode = new osg::MatrixTransform;
// rootnode->setMatrix(osg::Matrix::rotate(osg::inDegrees(30.0f),1.0f,0.0f,0.0f));
rootnode->addChild(model);
// run optimization over the scene graph
osgUtil::Optimizer optimzer;
//optimzer.optimize(rootnode);
// add a viewport to the viewer and attach the scene graph.
viewer.addViewport( rootnode );
// register trackball, flight and drive.
viewer.registerCameraManipulator(new osgGA::TrackballManipulator);
viewer.registerCameraManipulator(new osgGA::FlightManipulator);
viewer.registerCameraManipulator(new osgGA::DriveManipulator);
// open the viewer window.
viewer.open();
// fire up the event loop.
viewer.run();
return 0;
}