Dogcows Code - chaz/yoink/blob - src/Moof/Frustum.cc

   1
   2 /*******************************************************************************
   3
   4  Copyright (c) 2009, Charles McGarvey
   5  All rights reserved.
   6
   7  Redistribution   and   use  in  source  and  binary  forms,  with  or  without
   8  modification, are permitted provided that the following conditions are met:
   9
  10    * Redistributions  of  source  code  must retain the above copyright notice,
  11      this list of conditions and the following disclaimer.
  12    * Redistributions  in binary form must reproduce the above copyright notice,
  13      this  list of conditions and the following disclaimer in the documentation
  14      and/or other materials provided with the distribution.
  15
  16  THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  17  AND  ANY  EXPRESS  OR  IMPLIED  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  DISCLAIMED.  IN  NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  20  FOR  ANY  DIRECT,  INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  DAMAGES  (INCLUDING,  BUT  NOT  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  22  SERVICES;  LOSS  OF  USE,  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  23  CAUSED  AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  24  OR  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  25  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26
  27 *******************************************************************************/
  28
  29 #include <Moof/Aabb.hh>
  30 #include <Moof/Frustum.hh>
  31 #include <Moof/Sphere.hh>
  32
  33
  34 namespace Mf {
  35
  36
  37 void Frustum::init(const Matrix4& modelview, const Matrix4& projection)
  38 {
  39         Scalar planes[6][4];
  40
  41         cml::extract_frustum_planes(modelview, projection, planes,
  42                         cml::z_clip_neg_one);
  43
  44         planes_[0] = Plane(planes[0][0], planes[0][1], planes[0][2], planes[0][3]);
  45         planes_[1] = Plane(planes[1][0], planes[1][1], planes[1][2], planes[1][3]);
  46         planes_[2] = Plane(planes[2][0], planes[2][1], planes[2][2], planes[2][3]);
  47         planes_[3] = Plane(planes[3][0], planes[3][1], planes[3][2], planes[3][3]);
  48         planes_[4] = Plane(planes[4][0], planes[4][1], planes[4][2], planes[4][3]);
  49         planes_[5] = Plane(planes[5][0], planes[5][1], planes[5][2], planes[5][3]);
  50 }
  51
  52 void Frustum::init(const Matrix4& modelview, Scalar fovy, Scalar aspect,
  53                 Scalar abutting, Scalar distant)
  54 {
  55         Matrix4 projection;
  56
  57         cml::matrix_perspective_yfov_RH(projection, fovy, aspect, abutting, distant,
  58                         cml::z_clip_neg_one);
  59
  60         init(modelview, projection);
  61 }
  62
  63 Frustum::Collision Frustum::contains(const Aabb& aabb) const
  64 {
  65         Vector3 corners[8];
  66         int nTotalInside = 0;
  67
  68         aabb.getCorners(corners);
  69
  70         for (int i = 0; i < 6; ++i)
  71         {
  72                 int nInside = 8;
  73
  74                 for (int j = 0; j < 8; ++j)
  75                 {
  76                         if (planes_[i].intersects(corners[j]) ==
  77                                         Plane::NEGATIVE)
  78                         {
  79                                 --nInside;
  80                         }
  81                 }
  82
  83                 if (nInside == 0)      return OUTSIDE;
  84                 else if (nInside == 8) ++nTotalInside;
  85         }
  86
  87         if (nTotalInside == 6) return INSIDE;
  88         else                   return INTERSECT;
  89 }
  90
  91
  92 Frustum::Collision Frustum::contains(const Sphere& sphere) const
  93 {
  94         for (int i = 0; i < 6; ++i)
  95         {
  96                 Plane::Halfspace halfspace = planes_[i].intersects(sphere);
  97
  98                 if (halfspace == Plane::NEGATIVE)       return OUTSIDE;
  99                 else if (halfspace == Plane::INTERSECT) return INTERSECT;
 100         }
 101
 102         return INSIDE;
 103 }
 104
 105
 106 } // namespace Mf
 107
 108 /** vim: set ts=4 sw=4 tw=80: *************************************************/
 109