glMatrixMode - specify which matrix is the current matrix

glMatrixMode
	glMatrixMode(mode) -> None

void glMatrixMode( GLenum mode )

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.

glMatrixMode sets the	current	matrix mode.  mode can assume
one of three 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.

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

GL_INVALID_ENUM is generated if mode is not an accepted
value.

GL_INVALID_OPERATION is generated if glMatrixMode is
executed between the execution of glBegin and	the
corresponding	execution of glEnd.

glGet	with argument GL_MATRIX_MODE

glLoadMatrix,	glPushMatrix