1 /*************************************************************************

     2  *                                                                       *

     3  * Open Dynamics Engine, Copyright (C) 2001-2003 Russell L. Smith.       *

     4  * All rights reserved.  Email: russ@q12.org   Web: www.q12.org          *

     5  *                                                                       *

     6  * This library is free software; you can redistribute it and/or         *

     7  * modify it under the terms of EITHER:                                  *

     8  *   (1) The GNU Lesser General Public License as published by the Free  *

     9  *       Software Foundation; either version 2.1 of the License, or (at  *

    10  *       your option) any later version. The text of the GNU Lesser      *

    11  *       General Public License is included with this library in the     *

    12  *       file LICENSE.TXT.                                               *

    13  *   (2) The BSD-style license that is included with this library in     *

    14  *       the file LICENSE-BSD.TXT.                                       *

    15  *                                                                       *

    16  * This library is distributed in the hope that it will be useful,       *

    17  * but WITHOUT ANY WARRANTY; without even the implied warranty of        *

    18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files    *

    19  * LICENSE.TXT and LICENSE-BSD.TXT for more details.                     *

    20  *                                                                       *

    21  *************************************************************************/

    22 

    23 /*

    24 

    25 stuff common to all spaces

    26 

    27 */

    28 

    29 #ifndef _ODE_COLLISION_SPACE_INTERNAL_H_

    30 #define _ODE_COLLISION_SPACE_INTERNAL_H_

    31 

    32 #define ALLOCA(x) dALLOCA16(x)

    33 

    34 

    35 

    36 

    37 // collide two geoms together. for the hash table space, this is

    38 // called if the two AABBs inhabit the same hash table cells.

    39 // this only calls the callback function if the AABBs actually

    40 // intersect. if a geom has an AABB test function, that is called to

    41 // provide a further refinement of the intersection.

    42 //

    43 // NOTE: this assumes that the geom AABBs are valid on entry

    44 // and that both geoms are enabled.

    45 

    46 static void collideAABBs (dxGeom *g1, dxGeom *g2,

    47 			  void *data, dNearCallback *callback)

    48 {

    49 

    50 

    51   // no contacts if both geoms on the same body, and the body is not 0

    52   if (g1->body == g2->body && g1->body) return;

    53 

    54   // test if the category and collide bitfields match

    55   if ( ((g1->category_bits & g2->collide_bits) ||

    56 	(g2->category_bits & g1->collide_bits)) == 0) {

    57     return;

    58   }

    59 

    60   // if the bounding boxes are disjoint then don't do anything

    61   dReal *bounds1 = g1->aabb;

    62   dReal *bounds2 = g2->aabb;

    63   if (bounds1[0] > bounds2[1] ||

    64       bounds1[1] < bounds2[0] ||

    65       bounds1[2] > bounds2[3] ||

    66       bounds1[3] < bounds2[2] ||

    67       bounds1[4] > bounds2[5] ||

    68       bounds1[5] < bounds2[4]) {

    69     return;

    70   }

    71 

    72   // check if either object is able to prove that it doesn't intersect the

    73   // AABB of the other

    74   if (g1->AABBTest (g2,bounds2) == 0) return;

    75   if (g2->AABBTest (g1,bounds1) == 0) return;

    76 

    77   // the objects might actually intersect - call the space callback function

    78   callback (data,g1,g2);

    79 }

    80 

    81 #endif