dlls/d3dx8/mesh.c

   1 /*
   2  * Copyright 2008 David Adam
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19 #include "windef.h"
  20 #include "wingdi.h"
  21 #include "d3dx8.h"
  22
  23 #include "wine/debug.h"
  24
  25 WINE_DEFAULT_DEBUG_CHANNEL(d3dx);
  26
  27 BOOL WINAPI D3DXSphereBoundProbe(CONST D3DXVECTOR3 *pcenter, FLOAT radius, CONST D3DXVECTOR3 *prayposition, CONST D3DXVECTOR3 *praydirection)
  28 {
  29     D3DXVECTOR3 difference;
  30     FLOAT a, b, c;
  31
  32     a = D3DXVec3LengthSq(praydirection);
  33     if (!D3DXVec3Subtract(&difference, prayposition, pcenter)) return FALSE;
  34     b = D3DXVec3Dot(&difference, praydirection);
  35     c = D3DXVec3LengthSq(&difference) - radius * radius;
  36
  37     if ( b * b - a * c <= 0.0f ) return FALSE;
  38     return TRUE;
  39 }