| /* |
| ** License Applicability. Except to the extent portions of this file are |
| ** made subject to an alternative license as permitted in the SGI Free |
| ** Software License B, Version 1.1 (the "License"), the contents of this |
| ** file are subject only to the provisions of the License. You may not use |
| ** this file except in compliance with the License. You may obtain a copy |
| ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600 |
| ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at: |
| ** |
| ** http://oss.sgi.com/projects/FreeB |
| ** |
| ** Note that, as provided in the License, the Software is distributed on an |
| ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS |
| ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND |
| ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A |
| ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT. |
| ** |
| ** Original Code. The Original Code is: OpenGL Sample Implementation, |
| ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics, |
| ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc. |
| ** Copyright in any portions created by third parties is as indicated |
| ** elsewhere herein. All Rights Reserved. |
| ** |
| ** Additional Notice Provisions: The application programming interfaces |
| ** established by SGI in conjunction with the Original Code are The |
| ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released |
| ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version |
| ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X |
| ** Window System(R) (Version 1.3), released October 19, 1998. This software |
| ** was created using the OpenGL(R) version 1.2.1 Sample Implementation |
| ** published by SGI, but has not been independently verified as being |
| ** compliant with the OpenGL(R) version 1.2.1 Specification. |
| */ |
| |
| /* |
| * hull.c++ |
| * |
| * $Date: 2012/03/29 17:22:18 $ $Revision: 1.1.1.1 $ |
| * $Header: /cvs/bao-parsec/pkgs/libs/mesa/src/src/glu/sgi/libnurbs/internals/hull.cc,v 1.1.1.1 2012/03/29 17:22:18 uid42307 Exp $ |
| */ |
| |
| #include "glimports.h" |
| #include "myassert.h" |
| #include "mystdio.h" |
| #include "hull.h" |
| #include "gridvertex.h" |
| #include "gridtrimvertex.h" |
| #include "gridline.h" |
| #include "trimline.h" |
| #include "uarray.h" |
| #include "trimregion.h" |
| |
| Hull::Hull( void ) |
| {} |
| |
| Hull::~Hull( void ) |
| {} |
| |
| /*---------------------------------------------------------------------- |
| * Hull:init - this routine does the initialization needed before any |
| * calls to nextupper or nextlower can be made. |
| *---------------------------------------------------------------------- |
| */ |
| void |
| Hull::init( void ) |
| { |
| TrimVertex *lfirst = left.first(); |
| TrimVertex *llast = left.last(); |
| if( lfirst->param[0] <= llast->param[0] ) { |
| fakeleft.init( left.first() ); |
| upper.left = &fakeleft; |
| lower.left = &left; |
| } else { |
| fakeleft.init( left.last() ); |
| lower.left = &fakeleft; |
| upper.left = &left; |
| } |
| upper.left->last(); |
| lower.left->first(); |
| |
| if( top.ustart <= top.uend ) { |
| upper.line = ⊤ |
| upper.index = top.ustart; |
| } else |
| upper.line = 0; |
| |
| if( bot.ustart <= bot.uend ) { |
| lower.line = ⊥ |
| lower.index = bot.ustart; |
| } else |
| lower.line = 0; |
| |
| TrimVertex *rfirst = right.first(); |
| TrimVertex *rlast = right.last(); |
| if( rfirst->param[0] <= rlast->param[0] ) { |
| fakeright.init( right.last() ); |
| lower.right = &fakeright; |
| upper.right = &right; |
| } else { |
| fakeright.init( right.first() ); |
| upper.right = &fakeright; |
| lower.right = &right; |
| } |
| upper.right->first(); |
| lower.right->last(); |
| } |
| |
| /*---------------------------------------------------------------------- |
| * nextupper - find next vertex on upper hull of trim region. |
| * - if vertex is on trim curve, set vtop point to |
| * that vertex. if vertex is on grid, set vtop to |
| * point to temporary area and stuff coordinants into |
| * temporary vertex. Also, place grid coords in temporary |
| * grid vertex. |
| *---------------------------------------------------------------------- |
| */ |
| GridTrimVertex * |
| Hull::nextupper( GridTrimVertex *gv ) |
| { |
| if( upper.left ) { |
| gv->set( upper.left->prev() ); |
| if( gv->isTrimVert() ) return gv; |
| upper.left = 0; |
| } |
| |
| if( upper.line ) { |
| assert( upper.index <= upper.line->uend ); |
| gv->set( uarray.uarray[upper.index], upper.line->vval ); |
| gv->set( upper.index, upper.line->vindex ); |
| if( upper.index++ == upper.line->uend ) upper.line = 0; |
| return gv; |
| } |
| |
| if( upper.right ) { |
| gv->set( upper.right->next() ); |
| if( gv->isTrimVert() ) return gv; |
| upper.right = 0; |
| } |
| |
| return 0; |
| } |
| |
| GridTrimVertex * |
| Hull::nextlower( register GridTrimVertex *gv ) |
| { |
| if( lower.left ) { |
| gv->set( lower.left->next() ); |
| if( gv->isTrimVert() ) return gv; |
| lower.left = 0; |
| } |
| |
| if( lower.line ) { |
| gv->set( uarray.uarray[lower.index], lower.line->vval ); |
| gv->set( lower.index, lower.line->vindex ); |
| if( lower.index++ == lower.line->uend ) lower.line = 0; |
| return gv; |
| } |
| |
| if( lower.right ) { |
| gv->set( lower.right->prev() ); |
| if( gv->isTrimVert() ) return gv; |
| lower.right = 0; |
| } |
| |
| return 0; |
| } |
| |