[osg-users] filling colors into drawn Objects

[Srikanth Bemineni]

Hi

How do we fill color in a drawn object.Here I am trying to draw a circle 
and also I want to fill it with yellow  color.

1.What do you mean by actually setting this array ?
setTexCoordArray(0, texcoords);


2.What are these values or co-ordinates ?
(*texcoords)[j].set( 40.50f, 40.0f );

Even the tutorial doesn't have proper explanation for this

3.Can we support CGM(Computer Graphic Metadatafile) or Postscript 
importing of the screen ?

4.I am trying to antalias or draw smooth  lines but the opengl is not 
drawing the lines smoothly even if I have set Stateset ?
   osg::StateSet* StateSet = new osg::StateSet();
   osg::ref_ptr<osg::Hint> antialias = new 
osg::Hint(GL_LINE_SMOOTH_HINT, GL_NICEST);
   StateSet->setAttributeAndModes(antialias.get(), osg::StateAttribute::ON);
   what Am I doing wrong here ?
 


Srikanth Bemieni


/*****************************************************************************/
    //degree to radian conversion
    const float DEG2RAD = 3.14159/180;
    osg::Geode* circle = new osg::Geode;

    osg::Geometry* circleGeom = new osg::Geometry; //circle geometery
    circle->addDrawable( circleGeom );
    osg::Vec3Array* circleArray = new osg::Vec3Array;

    //To calculate circle points
    //here it is every 30 degrees 12 point circle or polygon what ever
    int radius  = 1000;
    for (int i=0; i < 360; i = i + 30 )
    {
        float degInRad = i*DEG2RAD;
        circleArray->push_back( 
osg::Vec3(cos(degInRad)*radius,0,sin(degInRad)*radius ) );
    }

    circleGeom->setVertexArray( circleArray );
    
    //attaching the points
    osg::DrawElementsUInt* circleelementobj = new  
osg::DrawElementsUInt( osg::PrimitiveSet::LINE_LOOP, 0 );

    osg::Vec4Array*  ccolors = new osg::Vec4Array;
    osg::TemplateIndexArray <unsigned int, 
osg::Array::UIntArrayType,4,4> *colorIndexArray;
    colorIndexArray =new osg::TemplateIndexArray<unsigned int, 
osg::Array::UIntArrayType,4,4>;

    osg::Vec2Array* texcoords = new osg::Vec2Array(360/30);

    for( int j=0 ; j < 360/30 ; j++ )
    {
        circleelementobj->push_back( j );
        ccolors->push_back(osg::Vec4(1.0f, 1.0f, 0.0f, 1.0f) ); //index 
0 redi
        (*texcoords)[j].set( 40.50f, 40.0f ); //I really didn't get what 
to do just copied from the tutorial
    }

    circleelementobj->push_back( 0 );

    for( int k = 0 ; k < 360 /30 ; k++ )
    {
        colorIndexArray->push_back(0);
    }

   
    ccolors->push_back(osg::Vec4(1.0f, 1.0f, 0.0f, 1.0f) ); //index 0 red

    circleGeom->addPrimitiveSet( circleelementobj );

    circleGeom->setColorArray(ccolors);
    circleGeom->setColorIndices(colorIndexArray);
    circleGeom->setColorBinding(osg::Geometry::BIND_PER_VERTEX);
    circleGeom->setTexCoordArray(0, texcoords);

     osg::PositionAttitudeTransform* circleXForm =
            new osg::PositionAttitudeTransform();


     circleXForm->setPosition(osg::Vec3( 4000 ,0, 4100 ));
     root->addChild(circleXForm);
     circleXForm->addChild( circle );
   
/*****************************************************************************************************************/

-- 
With Regards
Srikanth Bemineni
Geotrace Technologies
281-497-8440 extn 228
                                                                                                                                     
                                                                                                                   
                                                                                                                                     
                                                                                                                                   

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openscenegraph.org/pipermail/osg-users-openscenegraph.org/attachments/20080506/ae6160ce/attachment.htm>