OpenSceneGraph/examples/osgtexture1D/osgtexture1D.cpp
Robert Osfield 345810ef22 Added support for float or double osg::Plane, and the default osg::Plane to double.
Performance tests on big models did not indicate any performance penalty in using doubles over floats,
so the move to doubles should mainly impact precision improvements for whole earth databases.

Also made improvements to osgUtil::PlaneIntersector and osgSim::ElevationSlice classes
2006-11-28 16:00:52 +00:00

240 lines
8.1 KiB
C++

#include <osg/Notify>
#include <osg/Texture1D>
#include <osg/TexGen>
#include <osg/Material>
#include <osgDB/Registry>
#include <osgDB/ReadFile>
#include <osgProducer/Viewer>
// Creates a stateset which contains a 1D texture which is populated by contour banded color
// this is then used in conjunction with TexGen to create contoured models, either in
// object linear coords - like contours on a map, or eye linear which contour the distance from
// the eye. An app callback toggles between the two tex gen modes.
osg::StateSet* create1DTextureStateToDecorate(osg::Node* loadedModel)
{
const osg::BoundingSphere& bs = loadedModel->getBound();
osg::Image* image = new osg::Image;
int noPixels = 1024;
// allocate the image data, noPixels x 1 x 1 with 4 rgba floats - equivilant to a Vec4!
image->allocateImage(noPixels,1,1,GL_RGBA,GL_FLOAT);
image->setInternalTextureFormat(GL_RGBA);
typedef std::vector<osg::Vec4> ColorBands;
ColorBands colorbands;
colorbands.push_back(osg::Vec4(0.0f,0.0,0.0,1.0f));
colorbands.push_back(osg::Vec4(1.0f,0.0,0.0,1.0f));
colorbands.push_back(osg::Vec4(1.0f,1.0,0.0,1.0f));
colorbands.push_back(osg::Vec4(0.0f,1.0,0.0,1.0f));
colorbands.push_back(osg::Vec4(0.0f,1.0,1.0,1.0f));
colorbands.push_back(osg::Vec4(0.0f,0.0,1.0,1.0f));
colorbands.push_back(osg::Vec4(1.0f,0.0,1.0,1.0f));
colorbands.push_back(osg::Vec4(1.0f,1.0,1.0,1.0f));
float nobands = colorbands.size();
float delta = nobands/(float)noPixels;
float pos = 0.0f;
// fill in the image data.
osg::Vec4* dataPtr = (osg::Vec4*)image->data();
for(int i=0;i<noPixels;++i,pos+=delta)
{
//float p = floorf(pos);
//float r = pos-p;
//osg::Vec4 color = colorbands[(int)p]*(1.0f-r);
//if (p+1<colorbands.size()) color += colorbands[(int)p+1]*r;
osg::Vec4 color = colorbands[(int)pos];
*dataPtr++ = color;
}
osg::Texture1D* texture = new osg::Texture1D;
texture->setWrap(osg::Texture1D::WRAP_S,osg::Texture1D::MIRROR);
texture->setFilter(osg::Texture1D::MIN_FILTER,osg::Texture1D::LINEAR);
texture->setImage(image);
float zBase = bs.center().z()-bs.radius();
float zScale = 2.0f/bs.radius();
osg::TexGen* texgen = new osg::TexGen;
texgen->setMode(osg::TexGen::OBJECT_LINEAR);
texgen->setPlane(osg::TexGen::S,osg::Plane(0.0f,0.0f,zScale,-zBase));
osg::Material* material = new osg::Material;
osg::StateSet* stateset = new osg::StateSet;
stateset->setTextureAttribute(0,texture,osg::StateAttribute::OVERRIDE);
stateset->setTextureMode(0,GL_TEXTURE_1D,osg::StateAttribute::ON|osg::StateAttribute::OVERRIDE);
stateset->setTextureMode(0,GL_TEXTURE_2D,osg::StateAttribute::OFF|osg::StateAttribute::OVERRIDE);
stateset->setTextureMode(0,GL_TEXTURE_3D,osg::StateAttribute::OFF|osg::StateAttribute::OVERRIDE);
stateset->setTextureAttribute(0,texgen,osg::StateAttribute::OVERRIDE);
stateset->setTextureMode(0,GL_TEXTURE_GEN_S,osg::StateAttribute::ON|osg::StateAttribute::OVERRIDE);
stateset->setAttribute(material,osg::StateAttribute::OVERRIDE);
return stateset;
}
// An app callback which alternates the tex gen mode between object linear and eye linear to illustrate what differences it makes.
class AnimateStateCallback : public osg::NodeCallback
{
public:
AnimateStateCallback() {}
void animateState(osg::StateSet* stateset,double time)
{
// here we simply get any existing texgen, and then increment its
// plane, pushing the R coordinate through the texture.
osg::StateAttribute* attribute = stateset->getTextureAttribute(0,osg::StateAttribute::TEXGEN);
osg::TexGen* texgen = dynamic_cast<osg::TexGen*>(attribute);
if (texgen)
{
const double timeInterval = 1.0f;
static double previousTime = time;
static bool state = false;
while (time>previousTime+timeInterval)
{
previousTime+=timeInterval;
state = !state;
}
if (state)
{
texgen->setMode(osg::TexGen::OBJECT_LINEAR);
}
else
{
texgen->setMode(osg::TexGen::EYE_LINEAR);
}
}
}
virtual void operator()(osg::Node* node, osg::NodeVisitor* nv)
{
osg::StateSet* stateset = node->getStateSet();
if (stateset && nv->getFrameStamp())
{
// we have an exisitng stateset, so lets animate it.
animateState(stateset,nv->getFrameStamp()->getReferenceTime());
}
// note, callback is repsonsible for scenegraph traversal so
// should always include call the traverse(node,nv) to ensure
// that the rest of cullbacks and the scene graph are traversed.
traverse(node,nv);
}
};
int main( int argc, char **argv )
{
// use an ArgumentParser object to manage the program arguments.
osg::ArgumentParser arguments(&argc,argv);
// set up the usage document, in case we need to print out how to use this program.
arguments.getApplicationUsage()->setDescription(arguments.getApplicationName()+" is the example which demonstrates use of 1D textures.");
arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+" [options] filename ...");
arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display this information");
// construct the viewer.
osgProducer::Viewer viewer(arguments);
// set up the value with sensible default event handlers.
viewer.setUpViewer(osgProducer::Viewer::STANDARD_SETTINGS);
// get details on keyboard and mouse bindings used by the viewer.
viewer.getUsage(*arguments.getApplicationUsage());
// if user request help write it out to cout.
if (arguments.read("-h") || arguments.read("--help"))
{
arguments.getApplicationUsage()->write(std::cout);
return 1;
}
// any option left unread are converted into errors to write out later.
arguments.reportRemainingOptionsAsUnrecognized();
// report any errors if they have occured when parsing the program aguments.
if (arguments.errors())
{
arguments.writeErrorMessages(std::cout);
return 1;
}
if (arguments.argc()<=1)
{
arguments.getApplicationUsage()->write(std::cout,osg::ApplicationUsage::COMMAND_LINE_OPTION);
return 1;
}
// load the images specified on command line
osg::Node* loadedModel = osgDB::readNodeFiles(arguments);
if (loadedModel)
{
osg::StateSet* stateset = create1DTextureStateToDecorate(loadedModel);
if (!stateset)
{
std::cout<<"Error: failed to create 1D texture state."<<std::endl;
return 1;
}
loadedModel->setStateSet(stateset);
loadedModel->setUpdateCallback(new AnimateStateCallback());
// add model to viewer.
viewer.setSceneData( loadedModel );
// create the windows and run the threads.
viewer.realize();
while( !viewer.done() )
{
// wait for all cull and draw threads to complete.
viewer.sync();
// update the scene by traversing it with the the update visitor which will
// call all node update callbacks and animations.
viewer.update();
// fire off the cull and draw traversals of the scene.
viewer.frame();
}
// wait for all cull and draw threads to complete.
viewer.sync();
// run a clean up frame to delete all OpenGL objects.
viewer.cleanup_frame();
// wait for all the clean up frame to complete.
viewer.sync();
}
else
{
osg::notify(osg::NOTICE)<<arguments.getApplicationUsage()->getCommandLineUsage()<<std::endl;
return 0;
}
return 0;
}