I recently started working with OpenGL ES for the iPhone, and I am having a bit of trouble with it. I want to be able to rotate an object with your fingers. My problem is that I have my object placed at (0, 0, -3), and I would like to rotate it about its center. I know that I need to translate back to the origin, rotate, and then bring it back to the original place. I think I am facing a problem because I am using a matrix to keep track (?) of all of my rotations/translation/scaling etc, and I think it may be combining the operations in a way that order is not even considered (so the two translations would cancel each other). I just started learning OpenGL a day ago and am a complete newbie, so my assumption may be wrong.

Here is the part of the in drawView that I am having trouble with:

GLfloat matrix[16]; 
glGetFloatv(GL_MODELVIEW_MATRIX, matrix);
glLoadIdentity();
glTranslatef(0, 0, 3); // bring to origin
glRotatef(self.angle, self.dy, self.dx, 0); // rotate 
glTranslatef(0, 0, -3); // put it back in place 
glMultMatrixf(matrix); // save the transformations performed

Help would be much appreciated, thank you!