ericw-tools/common/bsputils.cc

64 lines
1.9 KiB
C++

/* Copyright (C) 1996-1997 Id Software, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
See file, 'COPYING', for details.
*/
#include <common/bsputils.h>
#include <assert.h>
/* small helper that just retrieves the correct vertex from face->surfedge->edge lookups */
int GetSurfaceVertex(const bsp2_t *bsp, const bsp2_dface_t *f, int v)
{
int edge = f->firstedge + v;
edge = bsp->dsurfedges[edge];
if (edge < 0)
return bsp->dedges[-edge].v[1];
return bsp->dedges[edge].v[0];
}
static void
Vertex_GetPos(const bsp2_t *bsp, int num, vec3_t out)
{
assert(num >= 0 && num < bsp->numvertexes);
const dvertex_t *v = &bsp->dvertexes[num];
for (int i=0; i<3; i++)
out[i] = v->point[i];
}
void
Face_Normal(const bsp2_t *bsp, const bsp2_dface_t *f, vec3_t norm)
{
if (f->side)
VectorSubtract(vec3_origin, bsp->dplanes[f->planenum].normal, norm);
else
VectorCopy(bsp->dplanes[f->planenum].normal, norm);
}
plane_t
Face_Plane(const bsp2_t *bsp, const bsp2_dface_t *f)
{
const int vertnum = GetSurfaceVertex(bsp, f, 0);
vec3_t vertpos;
Vertex_GetPos(bsp, vertnum, vertpos);
plane_t res;
Face_Normal(bsp, f, res.normal);
res.dist = DotProduct(vertpos, res.normal);
return res;
}