root/branches/Dirk_CPtr/Tutorials/08materials.cpp

// OpenSG Tutorial Example: Materials
//
// This example shows how to create a material. Materials define the surface
// properties of the geometry, and change how they look.
//
// This example shows the usage of SimpleMaterial and SimpleTexturedMaterial.
// Call it with an image filename as a parameter.
//

// Headers
#include <OpenSG/OSGGLUT.h>
#include <OpenSG/OSGConfig.h>
#include <OpenSG/OSGSimpleGeometry.h>
#include <OpenSG/OSGGLUTWindow.h>
#include <OpenSG/OSGSimpleSceneManager.h>
#include <OpenSG/OSGBaseFunctions.h>
#include <OpenSG/OSGTransform.h>
#include <OpenSG/OSGGroup.h>

// new headers: 

// the headers for the SimpleMaterials
#include <OpenSG/OSGSimpleMaterial.h>
#include <OpenSG/OSGSimpleTexturedMaterial.h>
#include <OpenSG/OSGImage.h>


// Activate the OpenSG namespace
OSG_USING_NAMESPACE

// a separate transformation for every object
TransformPtr cyltrans, tortrans;


// The SimpleSceneManager to manage simple applications
SimpleSceneManager *mgr;

// forward declaration so we can have the interesting stuff upfront
int setupGLUT(int *argc, char *argv[]);

// redraw the window
void display(void)
{
    // create the matrix
    Matrix m;
    Real32 t = glutGet(GLUT_ELAPSED_TIME );
    
    // set the transforms' matrices
    m.setTransform(Vec3f(0, 0, osgSin(t / 1000.f) * 1.5),
                   Quaternion( Vec3f (1, 0, 0), t / 500.f));

    cyltrans->setMatrix(m);
    
    m.setTransform(Vec3f(osgSin(t / 1000.f), 0, 0),
                   Quaternion( Vec3f (0, 0, 1), t / 1000.f));

    tortrans->setMatrix(m);

    commitChanges();
    
    mgr->redraw();
}


// Initialize GLUT & OpenSG and set up the scene
int main(int argc, char **argv)
{
    // OSG init
    osgInit(argc,argv);

    // GLUT init
    int winid = setupGLUT(&argc, argv);

    // the connection between GLUT and OpenSG
    GLUTWindowPtr gwin= GLUTWindow::create();
    gwin->setId(winid);
    gwin->init();

    // create the scene
    
    // create a pretty simple graph: a Group with two Transforms as children,
    // each of which carries a single Geometry.
    
    // The scene group
    
    NodePtr  scene = Node::create();
    GroupPtr g     = Group::create();
    
    scene->setCore(g);
    
    // The cylinder and its transformation
    NodePtr     cyl    = Node::create();
    GeometryPtr cylgeo = makeCylinderGeo( 1.4, .3, 8, true, true, true );
    
    cyl->setCore(cylgeo);

    cyltrans = Transform::create();

    NodePtr cyltransnode = Node::create();
    cyltransnode->setCore (cyltrans);
    cyltransnode->addChild(cyl     );
    
    // add it to the scene
    scene->addChild(cyltransnode);
    
    // The torus and its transformation
    NodePtr     torus    = Node::create();
    GeometryPtr torusgeo = makeTorusGeo( .2, 1, 8, 12 );
    
    torus->setCore(torusgeo);
        
    tortrans = Transform::create();

    NodePtr tortransnode = Node::create();
    tortransnode->setCore (tortrans);
    tortransnode->addChild(torus   );
    
    // add it to the scene
    scene->addChild(tortransnode);

    // now create and assign the materials
 
    /*
        Materials in OpenSG are associated with the Geometry NodeCores, i.e.
        every Geometry knows its material.
        
        Right now there are two kinds of Materials: SimpleMaterial and
        SimpleTexturedMaterial.
        
        SimpleMaterial is a pretty direct wrapper of the OpenGL material
        characteristics. It has an ambient, diffuse, emission and specular
        color together with a shininess. It also defines the transparency of
        the material. Finally there are two flags. Lit defines if the material
        is influenced by light sources and the lighting calculation. If lit is
        false, only the diffuse color is used. ColorMaterial defines if and
        how the colors given in the object influence the lighting calculation.
        Possible values are GL_NONE, GL_EMISSION, GL_AMBIENT, GL_DIFFUSE,
        GL_SPECULAR and  GL_AMBIENT_AND_DIFFUSE. 
    */
    
    SimpleMaterialPtr m1 = SimpleMaterial::create();
    
    // when everything is changed, not setting the mask is ok
    m1->setAmbient      (Color3f(0.2,0.2,0.2));
    m1->setDiffuse      (Color3f(0.8,0.5,0.2));
    m1->setEmission     (Color3f(0.0,0.0,0.0));
    m1->setSpecular     (Color3f(1.0,1.0,1.0));
    m1->setShininess    (10);
    
    /*
        Transparent objects are rendered last and sorted from back to
        front, but only objectwise. Thus transparecy within an object is
        not handled correctly.
    */
    m1->setTransparency (0);
    
    /*
        The SimpleGeometry objects do not contain colors, turn
        ColorMaterial off.
    */
    m1->setColorMaterial(GL_NONE);
    

    // assign the material to the geometry
    cylgeo->setMaterial(m1);
    
    
    /*
        SimpleTexturedMaterial is a SimpleMaterial with a texture.
        
        The texture is specified using an Image, which can be created on the
        fly or loaded from a file. 
        
        Additionally the texture filters can be changed via the
        minFilter/magFilter fields. Possible values are taken from OpenGL's
        glTexParameter() function. MinFilter can be GL_NEAREST, GL_LINEAR, and
        the mipmap modes, the most common being GL_LINEAR_MIPMAP_LINEAR.
        MagFilter can be GL_NEAREST or GL_LINEAR.
        
        Textures are independent from the normal lighting calculations. How the
        texture is combined with the lighting color is define by the envMode.
        The possible values are taken from glTexEnv(). GL_MODULATE just
        multiplies the two, GL_REPLACE ignores the lighting color and just uses
        the texture.
        
        The option that the SimpleTexturedMaterial has is the ability to use
        spherical environment maps. These can be used to simulate reflective
        environments.
    */
      
    /*
        Images can be created directly from the data or loaded from disk.
        
        The Image can handle a variety of data formats, including 1, 2, 3 or 4
        component images, and 1, 2 or 3 dimensional data. It can load and save
        a variety of formats, exactly which depends on the configured
        libraries.
    */
    
    ImagePtr image = Image::create();
   
    if(argc > 1)
    {
        image->read(argv[1]);
    }
    else
    {
        UChar8 data[] = {  0xff, 0xff, 0xff,  0x80, 0x00, 0x00,
                           0x80, 0x00, 0x00,  0xff, 0xff, 0xff };

        image->set( Image::OSG_RGB_PF, 2, 2, 1, 1, 1, 0, data );
    }
    
    SimpleTexturedMaterialPtr m2 = SimpleTexturedMaterial::create();
    
    m2->setAmbient      (Color3f(0.3,0.3,0.3));
    m2->setDiffuse      (Color3f(0.2,0.8,0.8));
    m2->setEmission     (Color3f(0.0,0.0,0.0));
    m2->setSpecular     (Color3f(1.0,1.0,1.0));
    m2->setShininess    (20);
    m2->setTransparency (0);
    m2->setColorMaterial(GL_NONE);
        
    m2->setImage        (image);
    m2->setMinFilter    (GL_LINEAR_MIPMAP_LINEAR);
    m2->setMagFilter    (GL_NEAREST);
    m2->setEnvMode      (GL_MODULATE);
    m2->setEnvMap       (false);
    
    // assign the material to the geometry
    torusgeo->setMaterial(m2);

    commitChanges();

    // create the SimpleSceneManager helper
    mgr = new SimpleSceneManager;

    // tell the manager what to manage
    mgr->setWindow(gwin );
    mgr->setRoot  (scene);

    // show the whole scene
    mgr->showAll();

    // GLUT main loop
    glutMainLoop();

    return 0;
}

//
// GLUT callback functions
//

// react to size changes
void reshape(int w, int h)
{
    mgr->resize(w, h);
    glutPostRedisplay();
}

// react to mouse button presses
void mouse(int button, int state, int x, int y)
{
    if (state)
        mgr->mouseButtonRelease(button, x, y);
    else
        mgr->mouseButtonPress(button, x, y);
        
    glutPostRedisplay();
}

// react to mouse motions with pressed buttons
void motion(int x, int y)
{
    mgr->mouseMove(x, y);
    glutPostRedisplay();
}

// react to keys
void keyboard(unsigned char k, int x, int y)
{
    switch(k)
    {
        case 27:    
        {
            OSG::osgExit();
            exit(0);
        }
        break;

        case 's':
        {
            mgr->setStatistics(!mgr->getStatistics());
        }
        break;
    }
}

// setup the GLUT library which handles the windows for us
int setupGLUT(int *argc, char *argv[])
{
    glutInit(argc, argv);
    glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
    
    int winid = glutCreateWindow("OpenSG");
    
    glutReshapeFunc(reshape);
    glutDisplayFunc(display);
    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    glutKeyboardFunc(keyboard);

    // call the redraw function whenever there's nothing else to do
    glutIdleFunc(display);

    return winid;
}