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diff --git a/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/getlight.gl b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/getlight.gl new file mode 100644 index 000000000..14843c780 --- /dev/null +++ b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/getlight.gl @@ -0,0 +1,192 @@ +_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_ The first character in this file must be an '_'! +_C_ Anything on a line after _C_ is ignored +_define(_filters,tbl|eqn)_C_ +_C_ eqn is automatically replaced with neqn for nroff +_header(GetLight,return light source parameter values) +_names(GetLight,[fi]v) +.EQ +delim $$ +.EN +.SH PARAMETERS +_phead(_param1) +Specifies a light source. +The number of possible lights depends on the implementation, +but at least eight lights are supported. +They are identified by symbolic names of the form _const(LIGHT)$i$ +where 0 \(<= $ i $ < _const(MAX_LIGHTS). +_phead(_param2) +Specifies a light source parameter for _param1. +Accepted symbolic names are +_const(AMBIENT), +_const(DIFFUSE), +_const(SPECULAR), +_const(POSITION), +_const(SPOT_DIRECTION), +_const(SPOT_EXPONENT), +_const(SPOT_CUTOFF), +_const(CONSTANT_ATTENUATION), +_const(LINEAR_ATTENUATION), and +_const(QUADRATIC_ATTENUATION). +_phead(_param3) +Returns the requested data. +.SH DESCRIPTION +_cmnd returns in _param3 the value or values of a light source parameter. +_param1 names the light and is a symbolic name of the form _const(LIGHT)$i$ +for 0 \(<= $i$ < _const(MAX_LIGHTS), +where _const(MAX_LIGHTS) is an implementation dependent constant that is +greater than or equal to eight. +_param2 specifies one of ten light source parameters, +again by symbolic name. +.P +The following parameters are defined: +.TP 20 +_const(AMBIENT) +_param3 returns four integer or floating-point values representing the +ambient intensity of the light source. +Integer values, +when requested, +are linearly mapped from the internal floating-point representation +such that 1.0 maps to the most positive representable integer value, +and \-1.0 maps to the most negative representable integer value. +If the internal value is outside the range [\-1, 1], +the corresponding integer return value is undefined. The initial value is +(0, 0, 0, 1). +.TP +_const(DIFFUSE) +_param3 returns four integer or floating-point values representing the +diffuse intensity of the light source. +Integer values, +when requested, +are linearly mapped from the internal floating-point representation +such that 1.0 maps to the most positive representable integer value, +and \-1.0 maps to the most negative representable integer value. +If the internal value is outside the range [\-1, 1], +the corresponding integer return value is undefined. The initial value +for _const(LIGHT0) is (1, 1, 1, 1); for other lights, the +initial value is (0, 0, 0, 0). +.TP +_const(SPECULAR) +_param3 returns four integer or floating-point values representing the +specular intensity of the light source. +Integer values, +when requested, +are linearly mapped from the internal floating-point representation +such that 1.0 maps to the most positive representable integer value, +and \-1.0 maps to the most negative representable integer value. +If the internal value is outside the range [\-1, 1], +the corresponding integer return value is undefined. The initial value +for _const(LIGHT0) is (1, 1, 1, 1); for other lights, the +initial value is (0, 0, 0, 0). +.TP +_const(POSITION) +_param3 returns four integer or floating-point values representing the +position of the light source. +Integer values, +when requested, +are computed by rounding the internal floating-point values to the +nearest integer value. +The returned values are those maintained in eye coordinates. +They will not be equal to the values specified using _cmnd(Light), +unless the modelview matrix was identity at the time _cmnd(Light) was +called. The initial value is (0, 0, 1, 0). +.TP +_const(SPOT_DIRECTION) +_param3 returns three integer or floating-point values representing the +direction of the light source. +Integer values, +when requested, +are computed by rounding the internal floating-point values to the +nearest integer value. +The returned values are those maintained in eye coordinates. +They will not be equal to the values specified using _cmnd(Light), +unless the modelview matrix was identity at the time _cmnd(Light) was called. +Although spot direction is normalized before being used in the lighting +equation, +the returned values are the transformed versions of the specified values +prior to normalization. The initial value is (0, 0, \-1). +.TP +_const(SPOT_EXPONENT) +_param3 returns a single integer or floating-point value representing the +spot exponent of the light. +An integer value, +when requested, +is computed by rounding the internal floating-point representation to +the nearest integer. The initial value is 0. +.TP +_const(SPOT_CUTOFF) +_param3 returns a single integer or floating-point value representing the +spot cutoff angle of the light. +An integer value, +when requested, +is computed by rounding the internal floating-point representation to +the nearest integer. The initial value is 180. +.TP +_const(CONSTANT_ATTENUATION) +_param3 returns a single integer or floating-point value representing the +constant (not distance-related) attenuation of the light. +An integer value, +when requested, +is computed by rounding the internal floating-point representation to +the nearest integer. The initial value is 1. +.TP +_const(LINEAR_ATTENUATION ) +_param3 returns a single integer or floating-point value representing the +linear attenuation of the light. +An integer value, +when requested, +is computed by rounding the internal floating-point representation to +the nearest integer. The initial value is 0. +.TP +_const(QUADRATIC_ATTENUATION) +_param3 returns a single integer or floating-point value representing the +quadratic attenuation of the light. +An integer value, +when requested, +is computed by rounding the internal floating-point representation to +the nearest integer. The initial value is 0. +.SH NOTES +It is always the case that _const(LIGHT)$i$ = _const(LIGHT0) + $i$. +.P +If an error is generated, +no change is made to the contents of _param3. +.SH ERRORS +_const(INVALID_ENUM) is generated if _param1 or _param2 is not an +accepted value. +.P +_const(INVALID_OPERATION) is generated if _cmnd +is executed between the execution of _cmnd(Begin) +and the corresponding execution of _cmnd(End). +.SH SEE ALSO +_cmnd(Light) |