gluProject - map object coordinates to window	coordinates

gluProject
	gluProject(objx, objy, objz, modelMatrix = None, projMatrix = None, viewport = None) -> (winx, winy, winz)

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

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.

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 4x4
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

winZ = (v'(2)	+ 1) / 2

glGet, gluUnProject