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diff --git a/xc/extras/ogl-sample/main/doc/man/mangl/standard/blendfunc.gl b/xc/extras/ogl-sample/main/doc/man/mangl/standard/blendfunc.gl deleted file mode 100755 index 7afec2732..000000000 --- a/xc/extras/ogl-sample/main/doc/man/mangl/standard/blendfunc.gl +++ /dev/null @@ -1,264 +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_ 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(BlendFunc, specify pixel arithmetic) -_names(BlendFunc) -.EQ -delim $$ -.EN -.SH PARAMETERS -_phead(_param1) -Specifies how the red, green, blue, -and alpha source blending factors are computed. -The following symbolic constants are accepted: -_const(ZERO), -_const(ONE), -_const(DST_COLOR), -_const(ONE_MINUS_DST_COLOR), -_const(SRC_ALPHA), -_const(ONE_MINUS_SRC_ALPHA), -_const(DST_ALPHA), -_const(ONE_MINUS_DST_ALPHA), and -_const(SRC_ALPHA_SATURATE). -The initial value is _const(ONE). -.TE - -Additionally, if the _arbstring(imaging) extension is supported, the -following constants are accepted: -_const(CONSTANT_COLOR), -_const(ONE_MINUS_CONSTANT_COLOR), -_const(CONSTANT_ALPHA), -_const(ONE_MINUS_CONSTANT_ALPHA). -_phead(_param2) -Specifies how the red, green, blue, -and alpha destination blending factors are computed. -Eight symbolic constants are accepted: -_const(ZERO), -_const(ONE), -_const(SRC_COLOR), -_const(ONE_MINUS_SRC_COLOR), -_const(SRC_ALPHA), -_const(ONE_MINUS_SRC_ALPHA), -_const(DST_ALPHA), and -_const(ONE_MINUS_DST_ALPHA). -The initial value is _const(ZERO). -.TE - -Additionally, if the _arbstring(imaging) extension is supported, the -following constants are accepted: -_const(CONSTANT_COLOR), -_const(ONE_MINUS_CONSTANT_COLOR), -_const(CONSTANT_ALPHA), -_const(ONE_MINUS_CONSTANT_ALPHA). -.SH DESCRIPTION -In RGBA mode, pixels can be drawn using a function that blends -the incoming (source) RGBA values with the RGBA values -that are already in the frame buffer (the destination values). -Blending is initially disabled. -Use _cmnd(Enable) and _cmnd(Disable) with argument _const(BLEND) -to enable and disable blending. -.P -_cmnd defines the operation of blending when it is enabled. -_param1 specifies which of nine methods is used to scale the -source color components. -_param2 specifies which of eight methods is used to scale the -destination color components. -The eleven possible methods are described in the following table. -Each method defines four scale factors, -one each for red, green, blue, and alpha. -.P -In the table and in subsequent equations, source and destination -color components are referred to as -$(R sub s , G sub s , B sub s , A sub s )$ and -$(R sub d , G sub d , B sub d , A sub d )$. -The color specified by _cmnd(BlendColor) is referred to as -$(R sub c , G sub c , B sub c , A sub c )$. -They are understood to have integer values between 0 and -$(k sub R , k sub G , k sub B , k sub A )$, -where -.P -.RS -.ce -$k sub c ~=~ 2 sup m sub c - 1$ -.RE -.P -and -$(m sub R , m sub G , m sub B , m sub A )$ -is the number of red, -green, -blue, -and alpha bitplanes. -.P -Source and destination scale factors are referred to as -$(s sub R , s sub G , s sub B , s sub A )$ and -$(d sub R , d sub G , d sub B , d sub A )$. -The scale factors described in the table, -denoted $(f sub R , f sub G , f sub B , f sub A )$, -represent either source or destination factors. -All scale factors have range [0,\ 1]. -.P -.TS -center; -lb cb -l c . -_ -Parameter $(f sub R , ~~ f sub G , ~~ f sub B , ~~ f sub A )$ -_ -_const(ZERO) $(0, ~0, ~0, ~0 )$ -_const(ONE) $(1, ~1, ~1, ~1 )$ -_const(SRC_COLOR) $(R sub s / k sub R , ~G sub s / k sub G , ~B sub s / k sub B , ~A sub s / k sub A )$ -_const(ONE_MINUS_SRC_COLOR) $(1, ~1, ~1, ~1 ) ~-~ (R sub s / k sub R , ~G sub s / k sub G , ~B sub s / k sub B , ~A sub s / k sub A )$ -_const(DST_COLOR) $(R sub d / k sub R , ~G sub d / k sub G , ~B sub d / k sub B , ~A sub d / k sub A )$ -_const(ONE_MINUS_DST_COLOR) $(1, ~1, ~1, ~1 ) ~-~ (R sub d / k sub R , ~G sub d / k sub G , ~B sub d / k sub B , ~A sub d / k sub A )$ -_const(SRC_ALPHA) $(A sub s / k sub A , ~A sub s / k sub A , ~A sub s / k sub A , ~A sub s / k sub A )$ -_const(ONE_MINUS_SRC_ALPHA) $(1, ~1, ~1, ~1 ) ~-~ (A sub s / k sub A , ~A sub s / k sub A , ~A sub s / k sub A , ~A sub s / k sub A )$ -_const(DST_ALPHA) $(A sub d / k sub A , ~A sub d / k sub A , ~A sub d / k sub A , ~A sub d / k sub A )$ -_const(ONE_MINUS_DST_ALPHA) $(1, ~1, ~1, ~1 ) ~-~ (A sub d / k sub A , ~A sub d / k sub A , ~A sub d / k sub A , ~A sub d / k sub A )$ -_const(SRC_ALPHA_SATURATE) $(i, ~i, ~i, ~1 )$ -_const(CONSTANT_COLOR) $(R sub c, G sub c, B sub c, A sub c)$ -_const(ONE_MINUS_CONSTANT_COLOR) $(1, ~1, ~1, ~1 ) ~-~ (R sub c, G sub c, B sub c, A sub c)$ -_const(CONSTANT_ALPHA) $(A sub c, A sub c, A sub c, A sub c)$ -_const(ONE_MINUS_CONSTANT_ALPHA) $(1, ~1, ~1, ~1 ) ~-~ (A sub c, A sub c, A sub c, A sub c)$ -_ -.TE -.sp -In the table, -.P -.RS -.nf -.IP -$i ~=~ min (A sub s , ~k sub A ~-~ A sub d ) ~/~ k sub A$ -.fi -.RE -.P -To determine the blended RGBA values of a pixel when drawing in RGBA mode, -the system uses the following equations: -.P -.RS -.nf -.IP -$R sub d ~=~ mark min ( k sub R, ~R sub s~s sub R~+~R sub d~d sub R )$ -$G sub d ~=~ lineup min ( k sub G, ~G sub s~s sub G~+~G sub d~d sub G )$ -$B sub d ~=~ lineup min ( k sub B, ~B sub s~s sub B~+~B sub d~d sub B )$ -$A sub d ~=~ lineup min ( k sub A, ~A sub s~s sub A~+~A sub d~d sub A )$ -.fi -.RE -.P -Despite the apparent precision of the above equations, -blending arithmetic is not exactly specified, -because blending operates with imprecise integer color values. -However, -a blend factor that should be equal to 1 -is guaranteed not to modify its multiplicand, -and a blend factor equal to 0 reduces its multiplicand to 0. -For example, -when _param1 is _const(SRC_ALPHA), -_param2 is _const(ONE_MINUS_SRC_ALPHA), -and $A sub s$ is equal to $k sub A$, -the equations reduce to simple replacement: -.P -.RS -.nf -.IP -$R sub d ~=~ mark R sub s$ -$G sub d ~=~ lineup G sub s$ -$B sub d ~=~ lineup B sub s$ -$A sub d ~=~ lineup A sub s$ -.fi -.RE -.P -.SH EXAMPLES -.P -Transparency is best implemented using blend function -(_const(SRC_ALPHA), _const(ONE_MINUS_SRC_ALPHA)) -with primitives sorted from farthest to nearest. -Note that this transparency calculation does not require -the presence of alpha bitplanes in the frame buffer. -.P -Blend function -(_const(SRC_ALPHA), _const(ONE_MINUS_SRC_ALPHA)) -is also useful for rendering antialiased points and lines -in arbitrary order. -.P -Polygon antialiasing is optimized using blend function -.br -(_const(SRC_ALPHA_SATURATE), _const(ONE)) -with polygons sorted from nearest to farthest. -(See the _cmnd(Enable), _cmnd(Disable) reference page and the -_const(POLYGON_SMOOTH) argument for information on polygon antialiasing.) -Destination alpha bitplanes, -which must be present for this blend function to operate correctly, -store the accumulated coverage. -.SH NOTES -Incoming (source) alpha is correctly thought of as a material opacity, -ranging from 1.0 ($K sub A$), representing complete opacity, -to 0.0 (0), representing complete -transparency. -.P -When more than one color buffer is enabled for drawing, -the GL performs blending separately for each enabled buffer, -using the contents of that buffer for destination color. -(See _cmnd(DrawBuffer).) -.P -Blending affects only RGBA rendering. -It is ignored by color index renderers. -.P -_const(CONSTANT_COLOR), _const(ONE_MINUS_CONSTANT_COLOR), -_const(CONSTANT_ALPHA), _const(ONE_MINUS_CONSTANT_ALPHA) are only -available if the _arbstring(imaging) is supported by your implementation. -.SH ERRORS -_const(INVALID_ENUM) is generated if either _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 ASSOCIATED GETS -_cmnd(Get) with argument _const(BLEND_SRC) -.br -_cmnd(Get) with argument _const(BLEND_DST) -.br -_cmnd(IsEnabled) with argument _const(BLEND) -.br -.SH SEE ALSO -_cmnd(AlphaFunc), -_cmnd(BlendColor), -_cmnd(BlendEquation), -_cmnd(Clear), -_cmnd(DrawBuffer), -_cmnd(Enable), -_cmnd(LogicOp), -_cmnd(StencilFunc) |