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diff --git a/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/accum.gl b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/accum.gl new file mode 100644 index 000000000..5245f738b --- /dev/null +++ b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/accum.gl @@ -0,0 +1,170 @@ +_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(Accum,operate on the accumulation buffer) +_names(Accum) +.EQ +delim $$ +.EN +.SH PARAMETERS +_phead(_param1) +Specifies the accumulation buffer operation. +Symbolic constants +_const(ACCUM), +_const(LOAD), +_const(ADD), +_const(MULT), +and +_const(RETURN) are accepted. +_phead(_param2) +Specifies a floating-point value used in the accumulation buffer operation. +_param1 determines how _param2 is used. +.SH DESCRIPTION +The accumulation buffer is an extended-range color buffer. +Images are not rendered into it. +Rather, +images rendered into one of the color buffers +are added to the contents of the accumulation buffer after rendering. +Effects such as antialiasing (of points, lines, and polygons), +motion blur, +and depth of field can be created +by accumulating images generated with different transformation matrices. +.P +Each pixel in the accumulation buffer consists of +red, green, blue, and alpha values. +The number of bits per component in the accumulation buffer +depends on the implementation. You can examine this number +by calling _cmnd(GetIntegerv) four times, +with arguments _const(ACCUM_RED_BITS), +_const(ACCUM_GREEN_BITS), +_const(ACCUM_BLUE_BITS), +and _const(ACCUM_ALPHA_BITS). +Regardless of the number of bits per component, +the range of values stored by each component is [\-1,\ 1]. +The accumulation buffer pixels are mapped one-to-one with frame buffer pixels. +.P +_cmnd operates on the accumulation buffer. +The first argument, _param1, +is a symbolic constant that selects an accumulation buffer operation. +The second argument, _param2, +is a floating-point value to be used in that operation. +Five operations are specified: +_const(ACCUM), _const(LOAD), _const(ADD), +_const(MULT), and _const(RETURN). +.P +All accumulation buffer operations are limited +to the area of the current scissor box and applied identically to +the red, green, blue, and alpha components of each pixel. +If a _cmnd operation results in a value outside the range [\-1,\ 1], +the contents of an accumulation buffer pixel component are undefined. +.P +The operations are as follows: +.TP 14 +_const(ACCUM) +Obtains R, G, B, and A values +from the buffer currently selected for reading (see _cmnd(ReadBuffer)). +Each component value is divided by $2 sup n^-^1$, +where $n$ is the number of bits allocated to each color component +in the currently selected buffer. +The result is a floating-point value in the range [0,\ 1], +which is multiplied by _param2 and added to the corresponding pixel component +in the accumulation buffer, +thereby updating the accumulation buffer. +.TP +_const(LOAD) +Similar to _const(ACCUM), +except that the current value in the accumulation buffer is not used +in the calculation of the new value. +That is, the R, G, B, and A values from the currently selected buffer +are divided by $2 sup n^-^1$, +multiplied by _param2, +and then stored in the corresponding accumulation buffer cell, +overwriting the current value. +.TP +_const(ADD) +Adds _param2 to each R, G, B, and A +in the accumulation buffer. +.TP +_const(MULT) +Multiplies each R, G, B, and A +in the accumulation buffer by _param2 and returns the scaled component +to its corresponding accumulation buffer location. +.TP +_const(RETURN) +Transfers accumulation buffer values +to the color buffer or buffers currently selected for writing. +Each R, G, B, and A component is multiplied by _param2, +then multiplied by $2 sup n^-^1$, +clamped to the range [0,$~2 sup n^-^1 $], and stored +in the corresponding display buffer cell. +The only fragment operations that are applied to this transfer are +pixel ownership, +scissor, +dithering, +and color writemasks. +.P +To clear the accumulation buffer, call _cmnd(ClearAccum) with R, G, B, +and A values to set it to, then call _cmnd(Clear) with the +accumulation buffer enabled. +.SH NOTES +Only pixels within the current scissor box are updated by a +_cmnd operation. +.SH ERRORS +_const(INVALID_ENUM) is generated if _param1 is not an accepted value. +.P +_const(INVALID_OPERATION) is generated if there is no accumulation buffer. +.P +_const(INVALID_OPERATION) is generated if _cmnd +is executed between the execution of +_cmnd(Begin) and the corresponding execution of _cmnd(End). +.SH ASSOCIATED GETS +_cmnd(Get) with argument _const(ACCUM_RED_BITS) +.br +_cmnd(Get) with argument _const(ACCUM_GREEN_BITS) +.br +_cmnd(Get) with argument _const(ACCUM_BLUE_BITS) +.br +_cmnd(Get) with argument _const(ACCUM_ALPHA_BITS) +.SH SEE ALSO +_cmnd(Clear), +_cmnd(ClearAccum), +_cmnd(CopyPixels), +_cmnd(DrawBuffer), +_cmnd(Get), +_cmnd(ReadBuffer), +_cmnd(ReadPixels), +_cmnd(Scissor), +_cmnd(StencilOp) |