mapw2(3G)

NAME
     mapw2 - maps a point on the screen into 2-D world coordinates

C SPECIFICATION
     void mapw2(Object vobj, Screencoord sx, Screencoord sy,
                Coord *wx, Coord *wy)

PARAMETERS
     vobj   expects the transformations that map the displayed objects to
            world coordinates.

     sx     expects the x coordinate of the screen point to be mapped.

     sy     expects the y coordinate of the screen point to be mapped.

     wx     returns the corresponding x world coordinate.

     wy     returns the corresponding y world coordinate.

DESCRIPTION
     mapw2 is the 2-D version of mapw.  vobj is a viewing object that defines
     world space.  It contains only routines that affect the model-view
     matrix, the projection matrix, or the viewport specification.  sx and sy
     define a point in screen coordinates.  wx and wy return the corresponding
     world coordinates.  If the transformation is not 2-D, the result is
     undefined.

SEE ALSO
     mapw

NOTE
     This routine is available only in immediate mode.