fglMatrixMode(3G)

NAME
     fglMatrixMode - specify which matrix is the current matrix


FORTRAN SPECIFICATION
     SUBROUTINE fglMatrixMode( INTEGER*4 mode )


PARAMETERS
     mode  Specifies which matrix stack is the target for subsequent matrix
           operations.  Three values are accepted:  GL_MODELVIEW,
           GL_PROJECTION, and GL_TEXTURE.  The initial value is GL_MODELVIEW.

           Additionally, if the GL_ARB_imaging extension is supported,
           GL_COLOR is also accepted.

DESCRIPTION
     fglMatrixMode sets the current matrix mode.  mode can assume one of four
     values:

     GL_MODELVIEW             Applies subsequent matrix operations to the
                              modelview matrix stack.

     GL_PROJECTION            Applies subsequent matrix operations to the
                              projection matrix stack.

     GL_TEXTURE               Applies subsequent matrix operations to the
                              texture matrix stack.

     GL_COLOR                 Applies subsequent matrix operations to the
                              color matrix stack.

     To find out which matrix stack is currently the target of all matrix
     operations, call fglGet with argument GL_MATRIX_MODE. The initial value
     is GL_MODELVIEW.

ERRORS
     GL_INVALID_ENUM is generated if mode is not an accepted value.

     GL_INVALID_OPERATION is generated if fglMatrixMode is executed between
     the execution of fglBegin and the corresponding execution of fglEnd.

ASSOCIATED GETS
     fglGet with argument GL_MATRIX_MODE


MACHINE DEPENDENCIES
     RealityEngine, RealityEngine2, and VTX systems do not support color
     matrix transformations on images as they are loaded to or read back from
     texture memory.
     On Octane2 VPro systems, use of the texture q coordinate to achieve
     projective texture effects will be processed on a per-vertex basis
     instead of a per-pixel basis, unless the the texture matrix is set up to
     be projective.  (A projective texture matrix is defined to be one in
     which any of the 13th, 14th or 15th elements is non-zero.)  In addition,
     if either two-sided lighting or fragment lighting is in effect,
     projective texture effects will always be processed on a per-vertex
     basis.


SEE ALSO
     fglLoadMatrix, fglPushMatrix