Dogcows Code - chaz/yoink/blob - src/moof/plane.cc

   1
   2 /*]  Copyright (c) 2009-2010, Charles McGarvey  [**************************
   3 **]  All rights reserved.
   4 *
   5 * vi:ts=4 sw=4 tw=75
   6 *
   7 * Distributable under the terms and conditions of the 2-clause BSD license;
   8 * see the file COPYING for a complete text of the license.
   9 *
  10 **************************************************************************/
  11
  12 #include "aabb.hh"
  13 #include "plane.hh"
  14 #include "sphere.hh"
  15
  16
  17 namespace moof {
  18
  19
  20 plane::halfspace plane::intersects(const aabb<3>& aabb) const
  21 {
  22         vector3 corners[8];
  23         int nPositive = 8;
  24
  25         aabb.get_corners(corners);
  26
  27         for (int i = 0; i < 8; ++i)
  28         {
  29                 if (intersects(corners[i]) == negative)
  30                 {
  31                         --nPositive;
  32                 }
  33         }
  34
  35         if (nPositive == 0)      return negative;
  36         else if (nPositive == 8) return positive;
  37         else                     return intersecting;
  38 }
  39
  40 plane::halfspace plane::intersects(const sphere<3>& sphere) const
  41 {
  42         scalar distance = distance_to_point(sphere.point);
  43
  44         if (distance < -sphere.radius)     return negative;
  45         else if (distance < sphere.radius) return intersecting;
  46         else                               return positive;
  47 }
  48
  49
  50 } // namespace moof
  51