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

   1
   2 /*]  Copyright (c) 2009-2011, Charles McGarvey  [*****************************
   3 **]  All rights reserved.
   4 *
   5 * Distributable under the terms and conditions of the 2-clause BSD license;
   6 * see the file COPYING for a complete text of the license.
   7 *
   8 *****************************************************************************/
   9
  10 #include "aabb.hh"
  11 #include "frustum.hh"
  12 #include "sphere.hh"
  13
  14
  15 namespace moof {
  16
  17
  18 void frustum::init(const matrix4& modelview, const matrix4& projection)
  19 {
  20         scalar planes[6][4];
  21         extract_frustum_planes(modelview, projection, planes, z_clip_neg_one);
  22
  23         planes_[0] = plane(planes[0][0], planes[0][1], planes[0][2], planes[0][3]);
  24         planes_[1] = plane(planes[1][0], planes[1][1], planes[1][2], planes[1][3]);
  25         planes_[2] = plane(planes[2][0], planes[2][1], planes[2][2], planes[2][3]);
  26         planes_[3] = plane(planes[3][0], planes[3][1], planes[3][2], planes[3][3]);
  27         planes_[4] = plane(planes[4][0], planes[4][1], planes[4][2], planes[4][3]);
  28         planes_[5] = plane(planes[5][0], planes[5][1], planes[5][2], planes[5][3]);
  29 }
  30
  31 void frustum::init(const matrix4& modelview, scalar fovy, scalar aspect,
  32                 scalar abutting, scalar distant)
  33 {
  34         matrix4 projection;
  35         matrix_perspective_yfov_RH(projection,
  36                         fovy, aspect, abutting, distant, z_clip_neg_one);
  37         init(modelview, projection);
  38 }
  39
  40 frustum::collision frustum::contains(const aabb<3>& aabb) const
  41 {
  42         int     total = 0;
  43         vector3 corners[8];
  44         aabb.get_corners(corners);
  45
  46         for (int i = 0; i < 6; ++i)
  47         {
  48                 int num = 8;
  49                 for (int j = 0; j < 8; ++j)
  50                 {
  51                         if (planes_[i].intersects(corners[j]) == plane::negative)
  52                                 --num;
  53                 }
  54                 if (num == 0) return outside;
  55                 else if (num == 8) ++total;
  56         }
  57
  58         if (total == 6) return inside;
  59         return intersecting;
  60 }
  61
  62 frustum::collision frustum::contains(const sphere3& sphere) const
  63 {
  64         for (int i = 0; i < 6; ++i)
  65         {
  66                 plane::halfspace halfspace = planes_[i].intersects(sphere);
  67                 if (halfspace == plane::negative) return outside;
  68                 else if (halfspace == plane::intersecting) return intersecting;
  69         }
  70         return inside;
  71 }
  72
  73
  74 } // namespace moof
  75