OpenSceneGraph/examples/osgGLUTsimple/osgGLUTsimple.cpp

96 lines
2.8 KiB
C++

// C++ source file - (C) 2003 Robert Osfield, released under the OSGPL.
// (C) 2005 Mike Weiblen http://mew.cx/ released under the OSGPL.
// Simple example using GLUT to create an OpenGL window and OSG for rendering.
// Derived from osgsimple.cpp
#include <iostream>
#ifdef WIN32
#include <windows.h>
#endif
#include <GL/glut.h>
#include <osg/Timer>
#include <osgUtil/SceneView>
#include <osgDB/ReadFile>
osg::ref_ptr<osgUtil::SceneView> sceneView;
osg::Timer_t start_tick;
unsigned int frameNum;
osg::Matrix viewMatrix;
void display(void)
{
// set up the frame stamp for current frame to record the current time and frame number so that animtion code can advance correctly
osg::ref_ptr<osg::FrameStamp> frameStamp = new osg::FrameStamp;
frameStamp->setReferenceTime(osg::Timer::instance()->delta_s(start_tick,osg::Timer::instance()->tick()));
frameStamp->setFrameNumber( frameNum++ );
// pass frame stamp to the SceneView so that the update, cull and draw traversals all use the same FrameStamp
sceneView->setFrameStamp( frameStamp.get() );
// set the view
sceneView->setViewMatrix( viewMatrix );
// do the update traversal the scene graph - such as updating animations
sceneView->update();
// do the cull traversal, collect all objects in the view frustum into a sorted set of rendering bins
sceneView->cull();
// draw the rendering bins.
sceneView->draw();
// Swap Buffers
glutSwapBuffers();
glutPostRedisplay();
}
void reshape( int w, int h )
{
// update the viewport dimensions, in case the window has been resized.
sceneView->setViewport( 0, 0, w, h );
}
int main( int argc, char **argv )
{
glutInit(&argc, argv);
if (argc<2)
{
std::cout << argv[0] <<": requires filename argument." << std::endl;
return 1;
}
// load the scene.
osg::ref_ptr<osg::Node> loadedModel = osgDB::readNodeFile(argv[1]);
if (!loadedModel)
{
std::cout << argv[0] <<": No data loaded." << std::endl;
return 1;
}
glutInitDisplayMode( GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH | GLUT_ALPHA );
glutInitWindowPosition( 100, 100 );
glutInitWindowSize( 800, 600 );
glutCreateWindow( argv[0] );
glutDisplayFunc( display );
glutReshapeFunc( reshape );
// create the view of the scene.
sceneView = new osgUtil::SceneView;
sceneView->setDefaults();
sceneView->setSceneData(loadedModel.get());
// initialize the view to look at the center of the scene graph
const osg::BoundingSphere& bs = loadedModel->getBound();
viewMatrix.makeLookAt(bs.center()-osg::Vec3(0.0,2.0f*bs.radius(),0.0),bs.center(),osg::Vec3(0.0f,0.0f,1.0f));
// record the timer tick at the start of rendering.
start_tick = osg::Timer::instance()->tick();
frameNum = 0;
glutMainLoop();
return 0;
}
/*EOF*/