TriOps.h Source File

00001 /************************************************************** ggt-head beg
00002  *
00003  * GGT: Generic Graphics Toolkit
00004  *
00005  * Original Authors:
00006  *   Allen Bierbaum
00007  *
00008  * -----------------------------------------------------------------
00009  * File:          $RCSfile: TriOps.h,v $
00010  * Date modified: $Date: 2003/03/03 00:54:05 $
00011  * Version:       $Revision: 1.6 $
00012  * -----------------------------------------------------------------
00013  *
00014  *********************************************************** ggt-head end */
00015 /*************************************************************** ggt-cpr beg
00016 *
00017 * GGT: The Generic Graphics Toolkit
00018 * Copyright (C) 2001,2002 Allen Bierbaum
00019 *
00020 * This library is free software; you can redistribute it and/or
00021 * modify it under the terms of the GNU Lesser General Public
00022 * License as published by the Free Software Foundation; either
00023 * version 2.1 of the License, or (at your option) any later version.
00024 *
00025 * This library is distributed in the hope that it will be useful,
00026 * but WITHOUT ANY WARRANTY; without even the implied warranty of
00027 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
00028 * Lesser General Public License for more details.
00029 *
00030 * You should have received a copy of the GNU Lesser General Public
00031 * License along with this library; if not, write to the Free Software
00032 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
00033 *
00034  ************************************************************ ggt-cpr end */
00035 #ifndef _GMTL_TRIOPS_H_
00036 #define _GMTL_TRIOPS_H_
00037 
00038 #include <gmtl/Tri.h>
00039 
00040 namespace gmtl
00041 {
00054 template< class DATA_TYPE >
00055 Point<DATA_TYPE, 3> center( const Tri<DATA_TYPE>& tri )
00056 {
00057    const float one_third = (1.0f/3.0f);
00058    return (tri[0] + tri[1] + tri[2]) * one_third;
00059 }
00060 
00068 template< class DATA_TYPE >
00069 Vec<DATA_TYPE, 3> normal( const Tri<DATA_TYPE>& tri )
00070 {
00071    Vec<DATA_TYPE, 3> normal = cross( tri[1] - tri[0], tri[2] - tri[0] );
00072    normalize( normal );
00073    return normal;
00074 }
00090 template< class DATA_TYPE >
00091 bool operator==( const Tri<DATA_TYPE>& tri1, const Tri<DATA_TYPE>& tri2 )
00092 {
00093    return ( (tri1[0] == tri2[0]) &&
00094             (tri1[1] == tri2[1]) &&
00095             (tri1[2] == tri2[2]) );
00096 }
00097 
00106 template< class DATA_TYPE >
00107 bool operator!=( const Tri<DATA_TYPE>& tri1, const Tri<DATA_TYPE>& tri2 )
00108 {
00109    return (! (tri1 == tri2));
00110 }
00111 
00123 template< class DATA_TYPE >
00124 bool isEqual( const Tri<DATA_TYPE>& tri1, const Tri<DATA_TYPE>& tri2,
00125               const DATA_TYPE& eps )
00126 {
00127    gmtlASSERT( eps >= 0 );
00128    return ( isEqual(tri1[0], tri2[0], eps) &&
00129             isEqual(tri1[1], tri2[1], eps) &&
00130             isEqual(tri1[2], tri2[2], eps) );
00131 }
00134 } // namespace gmtl
00135 
00136 #endif
00137