NAME

C SPECIFICATION

	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

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

$v^{\prime }=P\times M\times v$

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

The window coordinates are then computed as follows:

$\mathrm{winX}=\mathrm{view}\left(0\right)+\mathrm{view}\left(2\right)*\left(v^{\prime }\right(0)+1)/2$

$\mathrm{winY}=\mathrm{view}\left(1\right)+\mathrm{view}\left(3\right)*\left(v^{\prime }\right(1)+1)/2.\mathrm{EN}.\mathrm{sp}.\mathrm{EQ}\mathrm{winZ}=\left(v^{\prime }\right(2)+1)/2$

SEE ALSO