Examples/Tutorial/02movingTorus.cpp

   1 // what follows here is the smallest OpenSG programm possible
   2 // most things used here are explained now or on the next few pages, so don't
   3 // worry if not everythings clear right at the beginning...
   4
   5 // Some needed inlcude files - these will become more, believe me ;)
   6 #ifdef OSG_BUILD_ACTIVE
   7 #include <OSGGLUT.h>
   8 #include <OSGConfig.h>
   9 #include <OSGSimpleGeometry.h>
  10 #include <OSGGLUTWindow.h>
  11 #include <OSGSimpleSceneManager.h>
  12 #else
  13 #include <OpenSG/OSGGLUT.h>
  14 #include <OpenSG/OSGConfig.h>
  15 #include <OpenSG/OSGSimpleGeometry.h>
  16 #include <OpenSG/OSGGLUTWindow.h>
  17 #include <OpenSG/OSGSimpleSceneManager.h>
  18 #endif
  19
  20 // The SimpleSceneManager is a little usefull class which helps us to
  21 // manage little scenes. It will be discussed in detail later on
  22 OSG::SimpleSceneManagerRefPtr mgr;
  23 OSG::TransformRecPtr          transCore;
  24
  25 // we have a forward declarion here, just to sort the code
  26 int setupGLUT( int *argc, char *argv[] );
  27
  28 int main(int argc, char **argv)
  29 {
  30     // Init the OpenSG subsystem
  31     OSG::osgInit(argc,argv);
  32
  33     {
  34         // We create a GLUT Window (that is almost the same for most applications)
  35         int winid = setupGLUT(&argc, argv);
  36         OSG::GLUTWindowRecPtr gwin= OSG::GLUTWindow::create();
  37         gwin->setGlutId(winid);
  38         gwin->init();
  39
  40         // That will be our whole scene for now : an incredible Torus
  41
  42         OSG::NodeRecPtr scene;
  43
  44         // create all that stuff we will need:
  45         //one geometry and one transform node
  46
  47         OSG::NodeRecPtr torus = OSG::makeTorus(.5, 2, 16, 16);
  48         OSG::NodeRecPtr transNode = OSG::Node::create();
  49
  50         transCore = OSG::Transform::create();
  51         OSG::Matrix m;
  52
  53         // now provide some data...
  54
  55         // no rotation at the beginning
  56         m.setIdentity();
  57
  58         // set the core to the matrix we created
  59         transCore->setMatrix(m);
  60
  61         // now "insert" the core into the node
  62         transNode->setCore(transCore);
  63         // add the torus as a child to
  64         // the transformation node
  65         transNode->addChild(torus);
  66
  67         // "declare" the transformation as root
  68         scene = transNode;
  69
  70         // Create and setup our little friend - the SSM
  71         mgr = OSG::SimpleSceneManager::create();
  72         mgr->setWindow(gwin );
  73         mgr->setRoot  (scene);
  74         mgr->showAll();
  75
  76         OSG::commitChanges();
  77     }
  78
  79     // Give Control to the GLUT Main Loop
  80     glutMainLoop();
  81
  82     return 0;
  83 }
  84
  85 // react to size changes
  86 void reshape(int w, int h)
  87 {
  88     mgr->resize(w, h);
  89     glutPostRedisplay();
  90 }
  91
  92 // just redraw our scene if this GLUT callback is invoked
  93 void display(void)
  94 {
  95     //--------------------------BEGIN_ADD
  96     OSG::Matrix m;
  97
  98     // get the time since the apllication startet
  99     OSG::Real32 time = glutGet(GLUT_ELAPSED_TIME );
 100
 101     // set the rotation
 102     m.setRotate(OSG::Quaternion(OSG::Vec3f(0,1,0), time/1000.f));
 103
 104     //apply the new matrix to our transform core
 105     transCore->setMatrix(m);
 106
 107     // Ordinarily a call to commitChanges should be placed here, since we
 108     // modify the scene and therefore invalidate bounding volumes on which
 109     // rendering depends.
 110     // Since we are using the SimpleSceneManager though, this is not needed,
 111     // it calls commitChanges internally (adding the call here anyways would
 112     // not be a big issue, just slightly inefficient).
 113
 114     //--------------------------END_ADD
 115
 116     mgr->redraw();
 117 }
 118
 119 // react to mouse button presses
 120 void mouse(int button, int state, int x, int y)
 121 {
 122     if (state)
 123         mgr->mouseButtonRelease(button, x, y);
 124     else
 125         mgr->mouseButtonPress(button, x, y);
 126
 127     glutPostRedisplay();
 128 }
 129
 130 // react to mouse motions with pressed buttons
 131 void motion(int x, int y)
 132 {
 133     mgr->mouseMove(x, y);
 134     glutPostRedisplay();
 135 }
 136
 137 //The GLUT subsystem is set up here. This is very similar to other GLUT applications
 138 //If you have worked with GLUT before, you may have the feeling of meeting old friends again,
 139 //if you have not used GLUT before that is no problem. GLUT will be introduced shortly on the
 140 //next section
 141
 142 int setupGLUT(int *argc, char *argv[])
 143 {
 144     glutInit(argc, argv);
 145     glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
 146
 147     int winid = glutCreateWindow("OpenSG First Application");
 148
 149     glutDisplayFunc(display);
 150     glutMouseFunc(mouse);
 151     glutMotionFunc(motion);
 152     glutReshapeFunc(reshape);
 153     glutIdleFunc(display);
 154
 155     return winid;
 156 }