question: public static void gluPerspective ( GL10 gl , double fovy , double aspect , double zNear , double zFar ) { double top = zNear * Math . tan ( fovy * ( Math . PI / 360.0 ) ) ; double bottom = - top ; double left = bottom * aspect ; double right = top * aspect ; gl . glFrustumf ( ( float ) left , ( float ) right , ( float ) bottom , ( float ) top , ( float ) zNear , ( float ) zFar ) ; }
target:  Set up a perspective projection matrix