aboutsummaryrefslogtreecommitdiffstats
path: root/quantum/color.c
blob: 8bd52444faa4f59390a7fcbe2ddda1c5bba4f34b (plain)
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
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
/* Copyright 2017 Jason Williams
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include "color.h"
#include "led_tables.h"
#include "progmem.h"

RGB hsv_to_rgb(HSV hsv) {
    RGB      rgb;
    uint8_t  region, remainder, p, q, t;
    uint16_t h, s, v;

    if (hsv.s == 0) {
#ifdef USE_CIE1931_CURVE
        rgb.r = rgb.g = rgb.b = pgm_read_byte(&CIE1931_CURVE[hsv.v]);
#else
        rgb.r = hsv.v;
        rgb.g = hsv.v;
        rgb.b = hsv.v;
#endif
        return rgb;
    }

    h = hsv.h;
    s = hsv.s;
#ifdef USE_CIE1931_CURVE
    v = pgm_read_byte(&CIE1931_CURVE[hsv.v]);
#else
    v = hsv.v;
#endif

    region    = h * 6 / 255;
    remainder = (h * 2 - region * 85) * 3;

    p = (v * (255 - s)) >> 8;
    q = (v * (255 - ((s * remainder) >> 8))) >> 8;
    t = (v * (255 - ((s * (255 - remainder)) >> 8))) >> 8;

    switch (region) {
        case 6:
        case 0:
            rgb.r = v;
            rgb.g = t;
            rgb.b = p;
            break;
        case 1:
            rgb.r = q;
            rgb.g = v;
            rgb.b = p;
            break;
        case 2:
            rgb.r = p;
            rgb.g = v;
            rgb.b = t;
            break;
        case 3:
            rgb.r = p;
            rgb.g = q;
            rgb.b = v;
            break;
        case 4:
            rgb.r = t;
            rgb.g = p;
            rgb.b = v;
            break;
        default:
            rgb.r = v;
            rgb.g = p;
            rgb.b = q;
            break;
    }

    return rgb;
}

#ifdef RGBW
#ifndef MIN
#    define MIN(a, b) ((a) < (b) ? (a) : (b))
#endif
void convert_rgb_to_rgbw(LED_TYPE *led) {
    // Determine lowest value in all three colors, put that into
    // the white channel and then shift all colors by that amount
    led->w = MIN(led->r, MIN(led->g, led->b));
    led->r -= led->w;
    led->g -= led->w;
    led->b -= led->w;
}
#endif