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

NAME
glDepthRangeIndexed - specify mapping of depth values from normalized device coordinates to window coordinates for a specified viewport C SPECIFICATION
void glDepthRangeIndexed(GLuint index, GLdouble nearVal, GLdouble farVal); PARAMETERS
index Specifies the index of the viewport whose depth range to update. 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. Each viewport has an independent depth range specified as 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). glDepthRangeIndexed specifies a linear mapping of the normalized depth coordinates in this range to window depth coordinates for a specified viewport. Thus, the values accepted by glDepthRangeIndexed are both clamped to this range before they are accepted. The index parameter specifies the index of first viewport whose depth range to modify and must be less than the value of GL_MAX_VIEWPORTS. nearVal and farVal specify near and far values of the depth range for the specified viewport, respectively. 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 the near plane distance be less than the far plane distance. Reverse mappings such as nearVal = 1, and farVal = 0 are acceptable. The type of the nearVal and farVal parameters was changed from GLclampd to GLdouble. This change is transparent to user code and is described in detail on the removedTypes() page. ERRORS
GL_INVALID_VALUE is generated if index is greater than or equal to the value of GL_MAX_VIEWPORTS. ASSOCIATED GETS
glGet() with argument GL_DEPTH_RANGE SEE ALSO
glDepthFunc(), glDepthRange(), glDepthRangeArray(), glPolygonOffset(), glViewportArray(), glViewport(), removedTypes() COPYRIGHT
Copyright (C) 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/. [FIXME: source] 05/30/2012 GLDEPTHRANGEINDEXED(3G)

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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)
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