37 lines
1.4 KiB
C
37 lines
1.4 KiB
C
|
/****************************************************************************
|
||
|
|
** gmio
|
||
|
|
** Copyright Fougue (2 Mar. 2015)
|
||
|
|
** contact@fougue.pro
|
||
|
|
**
|
||
|
|
** This software is a reusable library whose purpose is to provide complete
|
||
|
|
** I/O support for various CAD file formats (eg. STL)
|
||
|
|
**
|
||
|
|
** This software is governed by the CeCILL-B license under French law and
|
||
|
|
** abiding by the rules of distribution of free software. You can use,
|
||
|
|
** modify and/ or redistribute the software under the terms of the CeCILL-B
|
||
|
|
** license as circulated by CEA, CNRS and INRIA at the following URL
|
||
|
|
** "http://www.cecill.info/licences/Licence_CeCILL-B_V1-en.html".
|
||
|
|
****************************************************************************/
|
||
|
|
|
||
|
|
#include "stl_triangle.h"
|
||
|
|
|
||
|
|
#include "../gmio_core/internal/vecgeom_utils.h"
|
||
|
|
|
||
|
|
GMIO_INLINE struct gmio_stl_coords gmio_stl_coords_diff(
|
||
|
|
const struct gmio_stl_coords* u, const struct gmio_stl_coords* v)
|
||
|
|
{
|
||
|
|
struct gmio_stl_coords diff;
|
||
|
|
diff.x = u->x - v->x;
|
||
|
|
diff.y = u->y - v->y;
|
||
|
|
diff.z = u->z - v->z;
|
||
|
|
return diff;
|
||
|
|
}
|
||
|
|
|
||
|
|
void gmio_stl_triangle_compute_normal(struct gmio_stl_triangle* tri)
|
||
|
|
{
|
||
|
|
const struct gmio_stl_coords u = gmio_stl_coords_diff(&tri->v2, &tri->v1);
|
||
|
|
const struct gmio_stl_coords v = gmio_stl_coords_diff(&tri->v3, &tri->v1);
|
||
|
|
struct gmio_stl_coords* n = &tri->n;
|
||
|
|
gmio_cross_product_f32(u.x, u.y, u.z, v.x, v.y, v.z, &n->x, &n->y, &n->z);
|
||
|
|
}
|