Example #1
0
//
// The Graphics Callback runs in the application "client thread" (qhStart) and sets the transformations
// for the Red Sphere and Green Line of the Cursor. Also, this callback sets the WorldToDevice matrix
// for use in the ServoLoopCallback.
//
void GraphicsCallback(void)
{
    QHGLUT* localDisplayObject = QHGLUT::searchWindow("Coulomb Field Demo");//Get a Pointer to the display object
    Cursor* localDeviceCursor = Cursor::searchCursor("devCursor");//Get a pointer to the cursor
    Cylinder* localForceArrow = Cylinder::searchCylinder("forceArrow");//get a pointer to the cylinder
    Cone* localForceArrowTip = Cone::searchCone("forceArrowTip");//get a pointer to the cylinder
	Sphere* localCursorSphere = Sphere::searchSphere("cursorSphere");//get a pointer top the Sphere

	if( localDisplayObject == NULL || localDeviceCursor == NULL || localForceArrow == NULL || localCursorSphere == NULL)
		return;

	hduMatrix CylinderTransform;//Transformation for the Cylinder. This transform makes it point toward the Model
	hduVector3Dd localCursorPosition;
	hduVector3Dd DirectionVecX;
	hduVector3Dd PointOnPlane;
	hduVector3Dd DirectionVecY;
	hduVector3Dd DirectionVecZ;

	//Compute the world to device transform
    WorldToDevice = localDisplayObject->getWorldToDeviceTransform();

	// Set transform for Red Sphere
    localCursorPosition = localDeviceCursor->getPosition();//Get the local cursor position in World Space
	
	hduVector3Dd localCursorSpherePos = localCursorSphere->getTranslation();
	localCursorSphere->setTranslation(-localCursorSpherePos);
	localCursorSphere->setTranslation(localCursorPosition);//Set the position of the Sphere the same as the cursor
    
	////////////////////////////////////////////////////////////////////////////////////////////
	//Code to calculate the transform of the green cylinder to point along the force direction
	////////////////////////////////////////////////////////////////////////////////////////////
	hduMatrix DeviceToWorld = WorldToDevice.getInverse();
	HDdouble ForceMagnitude = forceVec.magnitude();
	DeviceToWorld[3][0] = 0.0;			   
	DeviceToWorld[3][1] = 0.0;			   
	DeviceToWorld[3][2] = 0.0;
	DirectionVecX = forceVec * DeviceToWorld;
    DirectionVecX.normalize();
    PointOnPlane.set(0.0,0.0,(DirectionVecX[0]*localCursorPosition[0] + DirectionVecX[1]*localCursorPosition[1] + DirectionVecX[2]*localCursorPosition[2])/DirectionVecX[2]);
    DirectionVecY = PointOnPlane  - localCursorPosition;
    DirectionVecY.normalize();

    DirectionVecZ = -DirectionVecY.crossProduct(DirectionVecX);

    CylinderTransform[0][0] = DirectionVecZ[0]; CylinderTransform[0][1] = DirectionVecZ[1]; CylinderTransform[0][2] = DirectionVecZ[2]; CylinderTransform[0][3] = 0.0;
    CylinderTransform[1][0] = DirectionVecX[0]; CylinderTransform[1][1] = DirectionVecX[1]; CylinderTransform[1][2] = DirectionVecX[2]; CylinderTransform[1][3] = 0.0;
    CylinderTransform[2][0] = DirectionVecY[0]; CylinderTransform[2][1] = DirectionVecY[1]; CylinderTransform[2][2] = DirectionVecY[2]; CylinderTransform[2][3] = 0.0;
    CylinderTransform[3][0] = 0.0             ; CylinderTransform[3][1] = 0.0             ; CylinderTransform[3][2] = 0.0             ; CylinderTransform[3][3] = 1.0;
    CylinderTransform = CylinderTransform * hduMatrix::createTranslation(localCursorPosition[0], localCursorPosition[1], localCursorPosition[2]);
    
    localForceArrow->update(chargeRadius/4, ForceMagnitude*50, 15);
    localForceArrow->setTranslation(localCursorPosition);
    localForceArrow->setTransform(CylinderTransform);

     hduMatrix ConeTransform = CylinderTransform * hduMatrix::createTranslation(DirectionVecX[0]
     * ForceMagnitude*50,DirectionVecX[1] * ForceMagnitude*50,DirectionVecX[2] * ForceMagnitude*50 );

    localForceArrowTip->setTransform(ConeTransform);
	/////////////////////////////////////////////
}
Example #2
0
void Parser::parseCylinder(Scene* scene, TransformNode* transform, const Material& mat)
{
  Cylinder* cylinder = 0;
  Material* newMat = 0;

  _tokenizer.Read( CYLINDER );
  _tokenizer.Read( LBRACE );

  for( ;; )
  {
    const Token* t = _tokenizer.Peek();

    switch( t->kind() )
    {
      case MATERIAL:
        delete newMat;
        newMat = parseMaterialExpression( scene, mat );
        break;
      case NAME:
        parseIdentExpression();
        break;
      case RBRACE:
         _tokenizer.Read( RBRACE );
        cylinder = new Cylinder(scene, newMat ? newMat : new Material(mat));
        cylinder->setTransform( transform );
        scene->add( cylinder );
        return;
      default:
        throw SyntaxErrorException( "Expected: cylinder attributes", _tokenizer );
    }
  }

}