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.
gluUnProject4 is available only if the GLU version is 1.3 or greater.
Copyright 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/.
gluUnProject4: man2/gluUnProject4.xml
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.
gluUnProject4 is available only if the GLU version is 1.3 or greater.