How do i get the Center position of opengl object iphone?
In my project.. I moving the opengl object randomly.. if i click on that opengl object.. i need to get the center position of that object..  Here is my Code..


	
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
 if (objShowing == YES) {
		
	 NSLog(@"touch count %d",[touches count]);
	 UITouch *touchA,*touchB;
	 CGPoint pointA, pointB;
	
		if ([touches count] == 1)
		{
			touchA = [[touches allObjects] objectAtIndex:0];
			
			pointA = [touchA locationInView:self];
			pointB = [touchA previousLocationInView:self];
		
			float yDistance = pointA.y - pointB.y;
			
			float xDistance = pointA.x - pointB.x;

			GLfloat totalRotation = sqrt(xDistance*xDistance + yDistance*yDistance);
			
			CATransform3D temporaryMatrix = CATransform3DRotate(currentCalculatedMatrix, totalRotation * M_PI / 180.0, 
																((xDistance/totalRotation) * currentCalculatedMatrix.m11 + (yDistance/totalRotation) * currentCalculatedMatrix.m12),
																((xDistance/totalRotation) * currentCalculatedMatrix.m21 + (yDistance/totalRotation) * currentCalculatedMatrix.m22),
																((xDistance/totalRotation) * currentCalculatedMatrix.m31 + (yDistance/totalRotation) * currentCalculatedMatrix.m32));
			if ((temporaryMatrix.m11 >= -50.0) && (temporaryMatrix.m11 <= 50.0))
				currentCalculatedMatrix = temporaryMatrix;
			else
			{
			}
			
			[self convert3DTransform:&currentCalculatedMatrix toMatrix:matrix];
			
			[self adjustView];
		}
}
}



-(void)adjustView{
	NSLog(@"adjusting View");
	[EAGLContext setCurrentContext:context];

	glMatrixMode(GL_MODELVIEW);
	glEnable(GL_NORMALIZE);
	
	glLoadIdentity();
	glScalef(_scale, _scale, 1.0f);
	glRotatef(-90, 0.0f, 0.0f, 1.0f);
	glRotatef(180, 0, 1, 0);
	
	glClearColor(0.0f, 0.0f, 0.0f, 0);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	
	glPushMatrix();
	
	//Finally load matrix
	glMultMatrixf(matrix);
	
	glRotatef(0, 0, 0, 1);
	glRotatef(-90, 1, 0, 0);

	
        drawTeapot(codesiz);
			
	
	glPopMatrix();
	glBindFramebufferOES(GL_FRAMEBUFFER_OES, viewFramebuffer);
	glBindRenderbufferOES(GL_RENDERBUFFER_OES, viewRenderbuffer);
	[context presentRenderbuffer:GL_RENDERBUFFER_OES];
	
	
}
How do i get the Center position of opengl object iphone?
===

In my project.. I moving the opengl object randomly.. if i click on that opengl object.. i need to get the center position of that object..  Here is my Code..


	
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
 if (objShowing == YES) {
		
	 NSLog(@"touch count %d",[touches count]);
	 UITouch *touchA,*touchB;
	 CGPoint pointA, pointB;
	
		if ([touches count] == 1)
		{
			touchA = [[touches allObjects] objectAtIndex:0];
			
			pointA = [touchA locationInView:self];
			pointB = [touchA previousLocationInView:self];
		
			float yDistance = pointA.y - pointB.y;
			
			float xDistance = pointA.x - pointB.x;

			GLfloat totalRotation = sqrt(xDistance*xDistance + yDistance*yDistance);
			
			CATransform3D temporaryMatrix = CATransform3DRotate(currentCalculatedMatrix, totalRotation * M_PI / 180.0, 
																((xDistance/totalRotation) * currentCalculatedMatrix.m11 + (yDistance/totalRotation) * currentCalculatedMatrix.m12),
																((xDistance/totalRotation) * currentCalculatedMatrix.m21 + (yDistance/totalRotation) * currentCalculatedMatrix.m22),
																((xDistance/totalRotation) * currentCalculatedMatrix.m31 + (yDistance/totalRotation) * currentCalculatedMatrix.m32));
			if ((temporaryMatrix.m11 >= -50.0) && (temporaryMatrix.m11 <= 50.0))
				currentCalculatedMatrix = temporaryMatrix;
			else
			{
			}
			
			[self convert3DTransform:&currentCalculatedMatrix toMatrix:matrix];
			
			[self adjustView];
		}
}
}



-(void)adjustView{
	NSLog(@"adjusting View");
	[EAGLContext setCurrentContext:context];

	glMatrixMode(GL_MODELVIEW);
	glEnable(GL_NORMALIZE);
	
	glLoadIdentity();
	glScalef(_scale, _scale, 1.0f);
	glRotatef(-90, 0.0f, 0.0f, 1.0f);
	glRotatef(180, 0, 1, 0);
	
	glClearColor(0.0f, 0.0f, 0.0f, 0);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	
	glPushMatrix();
	
	//Finally load matrix
	glMultMatrixf(matrix);
	
	glRotatef(0, 0, 0, 1);
	glRotatef(-90, 1, 0, 0);

	
        drawTeapot(codesiz);
			
	
	glPopMatrix();
	glBindFramebufferOES(GL_FRAMEBUFFER_OES, viewFramebuffer);
	glBindRenderbufferOES(GL_RENDERBUFFER_OES, viewRenderbuffer);
	[context presentRenderbuffer:GL_RENDERBUFFER_OES];
	
	
}