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diff --git a/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/rasterpos.gl b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/rasterpos.gl new file mode 100644 index 000000000..b24bf8b44 --- /dev/null +++ b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/rasterpos.gl @@ -0,0 +1,173 @@ +_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,eqn)_C_ +_C_ eqn is automatically replaced with neqn for nroff +_header(RasterPos,specify the raster position for pixel operations) +_names(RasterPos,[2-4][sifd]) +.EQ +delim $$ +.EN +.SH PARAMETERS +_phead(_param1 _param2 _param3 _param4) +Specify the $x$, $y$, $z$, and $w$ object coordinates +(if present) +for the raster position. +_names(RasterPos,[2-4][sifd]v) +.SH PARAMETERS +_phead(_param1) +Specifies a pointer to an array of two, +three, +or four elements, +specifying $x$, $y$, $z$, and $w$ coordinates, respectively. +.SH DESCRIPTION +The GL maintains a 3D position in window coordinates. +This position, +called the raster position, +is used to position pixel and bitmap write operations. It is +maintained with subpixel accuracy. +See _cmnd(Bitmap), _cmnd(DrawPixels), and _cmnd(CopyPixels). +.P +The current raster position consists of three window coordinates +($x$, $y$, $z$), +a clip coordinate value ($w$), +an eye coordinate distance, +a valid bit, +and associated color data and texture coordinates. +The $w$ coordinate is a clip coordinate, +because $w$ is not projected to window coordinates. +_cmnd(RasterPos4) specifies object coordinates $x$, $y$, $z$, and $w$ +explicitly. +_cmnd(RasterPos3) specifies object coordinate $x$, $y$, and $z$ explicitly, +while $w$ is implicitly set to 1. +_cmnd(RasterPos2) uses the argument values for $x$ and $y$ while +implicitly setting $z$ and $w$ to 0 and 1. +.P +The object coordinates presented by _cmnd are treated just like those +of a _cmnd(Vertex) command: +They are transformed by the current modelview and projection matrices +and passed to the clipping stage. +If the vertex is not culled, +then it is projected and scaled to window coordinates, +which become the new current raster position, +and the _const(CURRENT_RASTER_POSITION_VALID) flag is set. +If the vertex +.I is +culled, +then the valid bit is cleared and the current raster position +and associated color and texture coordinates are undefined. +.P +The current raster position also includes some associated color data +and texture coordinates. +If lighting is enabled, +then _const(CURRENT_RASTER_COLOR) +(in RGBA mode) +or _const(CURRENT_RASTER_INDEX) +(in color index mode) +is set to the color produced by the lighting calculation +(see _cmnd(Light), _cmnd(LightModel), and +.br +_cmnd(ShadeModel)). +If lighting is disabled, +current color +(in RGBA mode, state variable _const(CURRENT_COLOR)) +or color index +(in color index mode, state variable _const(CURRENT_INDEX)) +is used to update the current raster color. +.P +Likewise, +_const(CURRENT_RASTER_TEXTURE_COORDS) is updated as a function +of _const(CURRENT_TEXTURE_COORDS), +based on the texture matrix and the texture generation functions +(see _cmnd(TexGen)). +Finally, +the distance from the origin of the eye coordinate system to the +vertex as transformed by only the modelview matrix replaces +_const(CURRENT_RASTER_DISTANCE). +.P +Initially, the current raster position is (0, 0, 0, 1), +the current raster distance is 0, +the valid bit is set, +the associated RGBA color is (1, 1, 1, 1), +the associated color index is 1, +and the associated texture coordinates are (0, 0, 0, 1). +In RGBA mode, +_const(CURRENT_RASTER_INDEX) is always 1; +in color index mode, +the current raster RGBA color always maintains its initial value. +.SH NOTES +The raster position is modified both by _cmnd and by _cmnd(Bitmap). +.P +When the raster position coordinates are invalid, +drawing commands that are based on the raster position are +ignored (that is, they do not result in changes to GL state). +.P +Calling _cmnd(DrawElements), or _cmnd(DrawRangeElements) may leave the +current color or index indeterminate. +If _cmnd is executed while the current color or index is indeterminate, the +current raster color or current raster index remains indeterminate. +.P +To set a valid raster position outside the viewport, first set a valid +raster position, then call _cmnd(Bitmap) with NULL as the \f2bitmap\fP +parameter. +.P +When the _arbstring(imaging) extension is supported, there are distinct +raster texture coordinates for each texture unit. Each texture unit's +current ratster texture coordinates are updated by _cmnd. +.SH ERRORS +_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(CURRENT_RASTER_POSITION) +.br +_cmnd(Get) with argument _const(CURRENT_RASTER_POSITION_VALID) +.br +_cmnd(Get) with argument _const(CURRENT_RASTER_DISTANCE) +.br +_cmnd(Get) with argument _const(CURRENT_RASTER_COLOR) +.br +_cmnd(Get) with argument _const(CURRENT_RASTER_INDEX) +.br +_cmnd(Get) with argument _const(CURRENT_RASTER_TEXTURE_COORDS) +.SH SEE ALSO +_cmnd(Bitmap), +_cmnd(CopyPixels), +_cmnd(DrawArrays), +_cmnd(DrawElements), +_cmnd(DrawRangeElements), +_cmnd(DrawPixels), +_cmnd(TexCoord), +_cmnd(TexGen), +_cmnd(Vertex) |