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GLUPROJECT()                                                      GLUPROJECT()

NAME
       gluProject - map object coordinates to window coordinates

C SPECIFICATION
       GLint gluProject( GLdouble objX,
                         GLdouble objY,
                         GLdouble objZ,
                         const GLdouble *model,
                         const GLdouble *proj,
                         const GLint *view,
                         GLdouble* winX,
                         GLdouble* winY,
                         GLdouble* winZ )

PARAMETERS
       objX, objY, objZ
                       Specify the object coordinates.

       model           Specifies the current modelview matrix (as from a
                       glGetDoublev call).

       proj            Specifies the current projection matrix (as from a
                       glGetDoublev call).

       view            Specifies the current viewport (as from a glGetIntegerv
                       call).

       winX, winY, winZ
                       Return the computed window coordinates.

DESCRIPTION
       gluProject transforms the specified object coordinates into window
       coordinates using model, proj, and view. The result is stored in winX,
       winY, and winZ. A return value of GL_TRUE indicates success, a return
       value of GL_FALSE indicates failure.

       To compute the coordinates, let v = (objX, objY, objZ, 1.0) represented
       as a matrix with 4 rows and 1 column.  Then gluProject computes v^' as
       follows:

       v^' = P x M x v

       where P is the current projection matrix proj, M is the current
       modelview matrix model (both represented as 4 x 4 matrices in column-
       major order) and 'x' represents matrix multiplication.

       The window coordinates are then computed as follows:

       winX = view (0) + view (2) * (v^' (0) + 1) / 2

       winY = view (1) + view (3) * (v^' (1) + 1) / 2. EN. sp. EQ winZ = (v^'
       (2) + 1) / 2

SEE ALSO
       glGet, gluUnProject

                                                                  GLUPROJECT()