| /* |
| Copyright 2005-2010 Intel Corporation. All Rights Reserved. |
| |
| This file is part of Threading Building Blocks. |
| |
| Threading Building Blocks is free software; you can redistribute it |
| and/or modify it under the terms of the GNU General Public License |
| version 2 as published by the Free Software Foundation. |
| |
| Threading Building Blocks is distributed in the hope that it will be |
| useful, but WITHOUT ANY WARRANTY; without even the implied warranty |
| of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with Threading Building Blocks; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| |
| As a special exception, you may use this file as part of a free software |
| library without restriction. Specifically, if other files instantiate |
| templates or use macros or inline functions from this file, or you compile |
| this file and link it with other files to produce an executable, this |
| file does not by itself cause the resulting executable to be covered by |
| the GNU General Public License. This exception does not however |
| invalidate any other reasons why the executable file might be covered by |
| the GNU General Public License. |
| */ |
| |
| /* |
| The original source for this example is |
| Copyright (c) 1994-2008 John E. Stone |
| All rights reserved. |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| 1. Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| 2. Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| 3. The name of the author may not be used to endorse or promote products |
| derived from this software without specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS |
| OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| SUCH DAMAGE. |
| */ |
| |
| /* |
| * box.c - This file contains the functions for dealing with boxes. |
| * |
| * $Id: box.cpp,v 1.1.1.1 2012/03/29 17:22:19 uid42307 Exp $ |
| */ |
| |
| #include "machine.h" |
| #include "types.h" |
| #include "macros.h" |
| #include "box.h" |
| #include "vector.h" |
| #include "intersect.h" |
| #include "util.h" |
| |
| int box_bbox(void * obj, vector * min, vector * max) { |
| box * b = (box *) obj; |
| |
| *min = b->min; |
| *max = b->max; |
| |
| return 1; |
| } |
| |
| static object_methods box_methods = { |
| (void (*)(void *, void *))(box_intersect), |
| (void (*)(void *, void *, void *, void *))(box_normal), |
| box_bbox, |
| free |
| }; |
| |
| box * newbox(void * tex, vector min, vector max) { |
| box * b; |
| |
| b=(box *) rt_getmem(sizeof(box)); |
| memset(b, 0, sizeof(box)); |
| b->methods = &box_methods; |
| b->tex = (texture *)tex; |
| b->min = min; |
| b->max = max; |
| |
| return b; |
| } |
| |
| void box_intersect(box * bx, ray * ry) { |
| flt a, tx1, tx2, ty1, ty2, tz1, tz2; |
| flt tnear, tfar; |
| |
| tnear= -FHUGE; |
| tfar= FHUGE; |
| |
| if (ry->d.x == 0.0) { |
| if ((ry->o.x < bx->min.x) || (ry->o.x > bx->max.x)) return; |
| } |
| else { |
| tx1 = (bx->min.x - ry->o.x) / ry->d.x; |
| tx2 = (bx->max.x - ry->o.x) / ry->d.x; |
| if (tx1 > tx2) { a=tx1; tx1=tx2; tx2=a; } |
| if (tx1 > tnear) tnear=tx1; |
| if (tx2 < tfar) tfar=tx2; |
| } |
| if (tnear > tfar) return; |
| if (tfar < 0.0) return; |
| |
| if (ry->d.y == 0.0) { |
| if ((ry->o.y < bx->min.y) || (ry->o.y > bx->max.y)) return; |
| } |
| else { |
| ty1 = (bx->min.y - ry->o.y) / ry->d.y; |
| ty2 = (bx->max.y - ry->o.y) / ry->d.y; |
| if (ty1 > ty2) { a=ty1; ty1=ty2; ty2=a; } |
| if (ty1 > tnear) tnear=ty1; |
| if (ty2 < tfar) tfar=ty2; |
| } |
| if (tnear > tfar) return; |
| if (tfar < 0.0) return; |
| |
| if (ry->d.z == 0.0) { |
| if ((ry->o.z < bx->min.z) || (ry->o.z > bx->max.z)) return; |
| } |
| else { |
| tz1 = (bx->min.z - ry->o.z) / ry->d.z; |
| tz2 = (bx->max.z - ry->o.z) / ry->d.z; |
| if (tz1 > tz2) { a=tz1; tz1=tz2; tz2=a; } |
| if (tz1 > tnear) tnear=tz1; |
| if (tz2 < tfar) tfar=tz2; |
| } |
| if (tnear > tfar) return; |
| if (tfar < 0.0) return; |
| |
| add_intersection(tnear, (object *) bx, ry); |
| add_intersection(tfar, (object *) bx, ry); |
| } |
| |
| void box_normal(box * bx, vector * pnt, ray * incident, vector * N) { |
| vector a, b, c; |
| flt t; |
| |
| c.x=(bx->max.x + bx->min.x) / 2.0; |
| c.y=(bx->max.y + bx->min.y) / 2.0; |
| c.z=(bx->max.z + bx->min.z) / 2.0; |
| |
| VSub((vector *) pnt, &c, N); |
| b=(*N); |
| |
| a.x=fabs(N->x); |
| a.y=fabs(N->y); |
| a.z=fabs(N->z); |
| |
| N->x=0.0; N->y=0.0; N->z=0.0; |
| |
| t=MYMAX(a.x, MYMAX(a.y, a.z)); |
| |
| if (t==a.x) N->x=b.x; |
| |
| if (t==a.y) N->y=b.y; |
| |
| if (t==a.z) N->z=b.z; |
| |
| VNorm(N); |
| } |
| |