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Diffstat (limited to 'nx-X11/extras/ogl-sample/main/doc/man/manglu/standard/perspective.gl')
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diff --git a/nx-X11/extras/ogl-sample/main/doc/man/manglu/standard/perspective.gl b/nx-X11/extras/ogl-sample/main/doc/man/manglu/standard/perspective.gl deleted file mode 100644 index c33fdbd91..000000000 --- a/nx-X11/extras/ogl-sample/main/doc/man/manglu/standard/perspective.gl +++ /dev/null @@ -1,106 +0,0 @@ -_C_ License Applicability. Except to the extent portions of this file are -_C_ made subject to an alternative license as permitted in the SGI Free -_C_ Software License B, Version 1.1 (the "License"), the contents of this -_C_ file are subject only to the provisions of the License. You may not use -_C_ this file except in compliance with the License. You may obtain a copy -_C_ of the License at Silicon Graphics, Inc., attn: Legal Services, 1600 -_C_ Amphitheatre Parkway, Mountain View, CA 94043-1351, or at: -_C_ -_C_ http://oss.sgi.com/projects/FreeB -_C_ -_C_ Note that, as provided in the License, the Software is distributed on an -_C_ "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS -_C_ DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND -_C_ CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A -_C_ PARTICULAR PURPOSE, AND NON-INFRINGEMENT. -_C_ -_C_ Original Code. The Original Code is: OpenGL Sample Implementation, -_C_ Version 1.2.1, released January 26, 2000, developed by Silicon Graphics, -_C_ Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc. -_C_ Copyright in any portions created by third parties is as indicated -_C_ elsewhere herein. All Rights Reserved. -_C_ -_C_ Additional Notice Provisions: The application programming interfaces -_C_ established by SGI in conjunction with the Original Code are The -_C_ OpenGL(R) Graphics System: A Specification (Version 1.2.1), released -_C_ April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version -_C_ 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X -_C_ Window System(R) (Version 1.3), released October 19, 1998. This software -_C_ was created using the OpenGL(R) version 1.2.1 Sample Implementation -_C_ published by SGI, but has not been independently verified as being -_C_ compliant with the OpenGL(R) version 1.2.1 Specification. -_C_ -_C_ $Date: 2004/03/14 08:29:09 $ $Revision: 1.1.1.4 $ -_C_ The first character in this file must be an '_'! -_C_ Anything on a line after _C_ is ignored -_define(_filters,eqn)_C_ -_C_ eqn is automatically replaced with neqn for nroff -_header(Perspective, set up a perspective projection matrix) -_names(Perspective) -.EQ -delim $$ -.EN -.SH PARAMETERS -_phead(_param1) -Specifies the field of view angle, in degrees, in the \f2y\fP direction. -_phead(_param2) -Specifies the aspect ratio that determines -the field of view in the \f2x\fP direction. -The aspect ratio is the ratio of \f2x\fP (width) to \f2y\fP (height). -_phead(_param3) -Specifies the distance from the viewer to the near clipping plane -(always positive). -_phead(_param4) -Specifies the distance from the viewer to the far clipping plane -(always positive). -.SH DESCRIPTION -_cmnd specifies a viewing frustum into the world coordinate system. -In general, the aspect ratio in _cmnd should match the aspect ratio -of the associated viewport. For example, $ _eqnparam2 ~=~ 2.0 $ means -the viewer's -angle of view is twice as wide in \f2x\fP as it is in \f2y\fP. -If the viewport is -twice as wide as it is tall, it displays the image without distortion. -.P -The matrix generated by _cmnd is multipled by the current matrix, -just as if _glcmnd(MultMatrix) were called with the generated matrix. -To load the perspective matrix onto the current matrix stack instead, -precede the call to _cmnd with a call to _glcmnd(LoadIdentity). -.P -Given \f2f\fP defined as follows: -.sp -.ce -.EQ -f ~=~ cotangent"("{_eqnparam1 over 2}")" -.EN -.bp -The generated matrix is -.sp -.ce -.EQ -left ( ~~ down 130 { matrix { - ccol { {f over _eqnparam2} above 0 above 0 above 0 } - ccol { 0 above f above 0 above 0 } - ccol { 0 above 0 above {{_eqnparam4 + _eqnparam3} over {_eqnparam3 - _eqnparam4}} above -1 } - ccol { 0 above 0 above {{2 * _eqnparam4 * _eqnparam3} over {_eqnparam3 - _eqnparam4}} above 0} -}} ~~~ right ) -.EN - -.SH NOTES -Depth buffer precision is affected by the values specified for -_param3 and _param4. -The greater the ratio of _param4 to _param3 is, -the less effective the depth buffer will be at distinguishing between -surfaces that are near each other. -If -.sp -.ce -$r ~=~ _eqnparam4 over _eqnparam3$ -.sp -.P -roughly $log sub 2 r$ bits of depth buffer precision are lost. -Because $r$ approaches infinity as _param3 approaches 0, -_param3 must never be set to 0. -.SH SEE ALSO -_glcmnd(Frustum), _glcmnd(LoadIdentity), -_glcmnd(MultMatrix), _cmnd(Ortho2D) |