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diff --git a/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/evalmesh.gl b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/evalmesh.gl new file mode 100644 index 000000000..a5b363814 --- /dev/null +++ b/nx-X11/extras/ogl-sample/main/doc/man/mangl/standard/evalmesh.gl @@ -0,0 +1,189 @@ +_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(EvalMesh, compute a one- or two-dimensional grid of points or lines) +_names(EvalMesh1) +.EQ +delim $$ +.EN +.SH PARAMETERS +_phead(_param1) +In _cmnd(EvalMesh1), specifies whether to compute a one-dimensional mesh of points or lines. +Symbolic constants +_const(POINT) and +_const(LINE) are accepted. +_phead(_param2 _param3) +Specify the first and last integer values for grid domain variable $i$. +_names(EvalMesh2) +.SH PARAMETERS +_phead(_param1) +In _cmnd(EvalMesh2), specifies whether to compute a two-dimensional mesh of points, lines, +or polygons. +Symbolic constants +_const(POINT), +_const(LINE), and +_const(FILL) are accepted. +_phead(_param2 _param3) +Specify the first and last integer values for grid domain variable $i$. +_phead(_param4 _param5) +Specify the first and last integer values for grid domain variable $j$. +.SH DESCRIPTION +_cmnd(MapGrid) and _cmnd are used in tandem to efficiently +generate and evaluate a series of evenly-spaced map domain values. +_cmnd steps through the integer domain of a one- or two-dimensional grid, +whose range is the domain of the evaluation maps specified by +_cmnd(Map1) and _cmnd(Map2). +_param1(1) determines whether the resulting vertices are connected as +points, +lines, +or filled polygons. +.P +In the one-dimensional case, +_cmnd(EvalMesh1), +the mesh is generated as if the following code fragment were executed: +.nf +.IP +\f7 +glBegin( \f2type\f7 ); +for ( i = _param2; i <= _param3; i += 1 ) + glEvalCoord1( i$^cdot^DELTA u ~+~ u sub 1$ ); +glEnd(); +\fP +.RE +.fi +where +.sp +.in +$ DELTA u ~=~ (u sub 2 ~-~ u sub 1 ) ^/^ n$ +.sp +.in 0 +.P +and $n$, $u sub 1$, and $u sub 2$ are the arguments to the most recent +_cmnd(MapGrid1) command. +\f2type\fP is _const(POINTS) if _param1(1) is _const(POINT), +or _const(LINES) if _param1(1) is _const(LINE). +.P +The one absolute numeric requirement is that if $i ~=~ n$, then the +value computed from $ i^cdot^DELTA u ~+~ u sub 1$ is exactly $u sub 2$. +.P +In the two-dimensional case, _cmnd(EvalMesh2), let +.nf +.IP +$ DELTA u ~=~ mark ( u sub 2 ~-~ u sub 1 ) ^/^ n$ +.sp +$ DELTA v ~=~ lineup ( v sub 2 ~-~ v sub 1 ) ^/^ m$, +.fi +.RE +.P +where $n$, $u sub 1$, $u sub 2$, $m$, $v sub 1$, and $v sub 2$ are the +arguments to the most recent _cmnd(MapGrid2) command. Then, if +_param1(2) is _const(FILL), the _cmnd(EvalMesh2) command is equivalent +to: +.nf +.IP +\f7 +for ( j = _param4; j < _param5; j += 1 ) { + glBegin( GL_QUAD_STRIP ); + for ( i = _param2; i <= _param3; i += 1 ) { + glEvalCoord2( i$^cdot^DELTA u ~+~ u sub 1$, j$^cdot^DELTA v ~+~ v sub 1$ ); + glEvalCoord2( i$^cdot^DELTA u ~+~ u sub 1$, (j+1)$^cdot^DELTA v ~+~ v sub 1$ ); + } + glEnd(); +} +\fP +.RE +.fi +.P +If _param1 is _const(LINE), then a call to _cmnd(EvalMesh2) is equivalent to: +.nf +.IP +\f7 +for ( j = _param4; j <= _param5; j += 1 ) { + glBegin( GL_LINE_STRIP ); + for ( i = _param2; i <= _param3; i += 1 ) + glEvalCoord2( i$^cdot^DELTA u ~+~ u sub 1$, j$^cdot^DELTA v ~+~ v sub 1$ ); + glEnd(); +} +.sp +for ( i = _param2; i <= _param3; i += 1 ) { + glBegin( GL_LINE_STRIP ); + for ( j = _param4; j <= _param4; j += 1 ) + glEvalCoord2( i$^cdot^DELTA u ~+~ u sub 1$, j$^cdot^DELTA v ~+~ v sub 1 $ ); + glEnd(); +} +\fP +.RE +.fi +.P +And finally, if _param1 is _const(POINT), then a call to +_cmnd(EvalMesh2) is equivalent to: +.nf +.IP +\f7 +glBegin( GL_POINTS ); +for ( j = _param4; j <= _param5; j += 1 ) + for ( i = _param2; i <= _param3; i += 1 ) + glEvalCoord2( i$^cdot^DELTA u ~+~ u sub 1$, j$^cdot^DELTA v ~+~ v sub 1$ ); +glEnd(); +\fP +.RE +.fi +.P +In all three cases, the only absolute numeric requirements are that if $i~=~n$, +then the value computed from $i^cdot^DELTA u ~+~ u sub 1$ is exactly $u +sub 2$, and if $j~=~m$, then the value computed from +$j ^cdot^ DELTA v ~+~ v sub 1$ is exactly $v sub 2$. +.SH ERRORS +_const(INVALID_ENUM) is generated if _param1 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(MAP1_GRID_DOMAIN) +.br +_cmnd(Get) with argument _const(MAP2_GRID_DOMAIN) +.br +_cmnd(Get) with argument _const(MAP1_GRID_SEGMENTS) +.br +_cmnd(Get) with argument _const(MAP2_GRID_SEGMENTS) +.SH SEE ALSO +_cmnd(Begin), +_cmnd(EvalCoord), +_cmnd(EvalPoint), +_cmnd(Map1), +_cmnd(Map2), +_cmnd(MapGrid) |