1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
/*************************************************************************
* Copyright (C) 2010 Tavian Barnes <tavianator@gmail.com> *
* *
* This file is part of The Dimension Library. *
* *
* The Dimension Library is free software; you can redistribute it and/ *
* or modify it under the terms of the GNU Lesser General Public License *
* as published by the Free Software Foundation; either version 3 of the *
* License, or (at your option) any later version. *
* *
* The Dimension Library 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 *
* Lesser General Public License for more details. *
* *
* You should have received a copy of the GNU Lesser General Public *
* License along with this program. If not, see *
* <http://www.gnu.org/licenses/>. *
*************************************************************************/
#include "dimension.h"
#include <errno.h>
#include <math.h>
/*
* Reflective finish
*/
typedef struct dmnsn_reflection_params {
dmnsn_color min, max;
double falloff;
} dmnsn_reflection_params;
static dmnsn_color
dmnsn_reflective_finish_fn(const dmnsn_finish *finish,
dmnsn_color reflect, dmnsn_color color,
dmnsn_vector ray, dmnsn_vector normal)
{
dmnsn_reflection_params *params = finish->ptr;
double reflection = pow(fabs(dmnsn_vector_dot(ray, normal)), params->falloff);
return dmnsn_color_illuminate(
dmnsn_color_gradient(params->min, params->max, reflection),
reflect
);
}
dmnsn_finish *
dmnsn_new_reflective_finish(dmnsn_color min, dmnsn_color max, double falloff)
{
dmnsn_finish *finish = dmnsn_new_finish();
dmnsn_reflection_params *params
= dmnsn_malloc(sizeof(dmnsn_reflection_params));
params->min = min;
params->max = max;
params->falloff = falloff;
finish->ptr = params;
finish->reflection_fn = &dmnsn_reflective_finish_fn;
finish->free_fn = &free;
return finish;
}
|