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gluunproject4(3g) [centos man page]

GLUUNPROJECT4(3G)						   OpenGL Manual						 GLUUNPROJECT4(3G)

NAME

       gluUnProject4 - map window and clip coordinates to object coordinates

C SPECIFICATION

       GLint gluUnProject4(GLdouble winX, GLdouble winY, GLdouble winZ, GLdouble clipW, const GLdouble * model, const GLdouble * proj,
			   const GLint * view, GLdouble nearVal, GLdouble farVal, GLdouble* objX, GLdouble* objY, GLdouble* objZ, GLdouble* objW);

PARAMETERS

       winX, winY, winZ
	   Specify the window coordinates to be mapped.

       clipW
	   Specify the clip w coordinate to be mapped.

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

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

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

       nearVal, farVal
	   Specifies the near and far planes (as from a glGetDoublev() call).

       objX, objY, objZ, objW
	   Returns the computed object coordinates.

DESCRIPTION

       gluUnProject4 maps the specified window coordinatesi: winX, winY, and winZ and its clip w coordinate clipW into object coordinates objX
       objY objZ objW using model, proj, and view.  clipW can be other than 1 as for vertices in glFeedbackBuffer() when data type
       GLU_4D_COLOR_TEXTURE is returned. This also handles the case where the nearVal and farVal planes are different from the default, 0 and 1,
       respectively. A return value of GLU_TRUE indicates success; a return value of GLU_FALSE indicates failure.

       To compute the coordinates objX objY objZ objW, gluUnProject4 multiplies the normalized device coordinates by the inverse of model * proj
       as follows:

       objX objY objZ objW = INV  P  M	2  winX - view	0 view	2 - 1 2  winY - view  1 view  3 - 1 2  winZ - nearVal farVal - nearVal - 1 clipW

       INV denotes matrix inversion.

       gluUnProject4 is equivalent to gluUnProject() when clipW is 1, nearVal is 0, and farVal is 1.

NOTES

       gluUnProject4 is available only if the GLU version is 1.3 or greater.

SEE ALSO

       gluProject(), gluUnProject(), glFeedbackBuffer(), glGet()

COPYRIGHT

       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see
       http://oss.sgi.com/projects/FreeB/.

AUTHORS

       opengl.org

opengl.org							    06/10/2014							 GLUUNPROJECT4(3G)

Check Out this Related Man Page

GLDEPTHRANGE(3G)						  [FIXME: manual]						  GLDEPTHRANGE(3G)

NAME

       glDepthRange - specify mapping of depth values from normalized device coordinates to window coordinates

C SPECIFICATION

       void glDepthRange(GLdouble nearVal, GLdouble farVal);

       void glDepthRangef(GLfloat nearVal, GLfloat farVal);

PARAMETERS

       nearVal
	   Specifies the mapping of the near clipping plane to window coordinates. The initial value is 0.

       farVal
	   Specifies the mapping of the far clipping plane to window coordinates. The initial value is 1.

DESCRIPTION

       After clipping and division by w, depth coordinates range from -1 to 1, corresponding to the near and far clipping planes.  glDepthRange
       specifies a linear mapping of the normalized depth coordinates in this range to window depth coordinates. Regardless of the actual depth
       buffer implementation, window coordinate depth values are treated as though they range from 0 through 1 (like color components). Thus, the
       values accepted by glDepthRange are both clamped to this range before they are accepted.

       The setting of (0,1) maps the near plane to 0 and the far plane to 1. With this mapping, the depth buffer range is fully utilized.

NOTES

       It is not necessary that nearVal be less than farVal. Reverse mappings such as nearVal = 1, and farVal = 0 are acceptable.

       The type of the nearVal and farVal parameters was changed from GLclampf to GLfloat for glDepthRangef and from GLclampd to GLdouble for
       glDepthRange. This change is transparent to user code and is described in detail on the removedTypes() page.

ASSOCIATED GETS

       glGet() with argument GL_DEPTH_RANGE

SEE ALSO

       glDepthFunc(), glPolygonOffset(), glViewport(), removedTypes()

COPYRIGHT

       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see
       http://oss.sgi.com/projects/FreeB/.

[FIXME: source] 						    05/30/2012							  GLDEPTHRANGE(3G)
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