From 5e8efe8281206c3b7e7a5256efa74aa8561f47ae Mon Sep 17 00:00:00 2001
From: Willy-JL <49810075+Willy-JL@users.noreply.github.com>
Date: Mon, 14 Aug 2023 01:17:37 +0200
Subject: [PATCH] Add colors toolbox (rgb and hsv)

---
 firmware/targets/f7/api_symbols.csv |  2 +
 lib/toolbox/colors.c                | 87 +++++++++++++++++++++++++++++
 lib/toolbox/colors.h                | 27 +++++++++
 3 files changed, 116 insertions(+)
 create mode 100644 lib/toolbox/colors.c
 create mode 100644 lib/toolbox/colors.h

diff --git a/firmware/targets/f7/api_symbols.csv b/firmware/targets/f7/api_symbols.csv
index b53c19e90..3613133bd 100644
--- a/firmware/targets/f7/api_symbols.csv
+++ b/firmware/targets/f7/api_symbols.csv
@@ -1733,6 +1733,7 @@ Function,+,hex_char_to_hex_nibble,_Bool,"char, uint8_t*"
 Function,+,hex_char_to_uint8,_Bool,"char, char, uint8_t*"
 Function,+,hex_chars_to_uint64,_Bool,"const char*, uint64_t*"
 Function,+,hex_chars_to_uint8,_Bool,"const char*, uint8_t*"
+Function,+,hsv2rgb,RgbColor,HsvColor
 Function,-,hypot,double,"double, double"
 Function,-,hypotf,float,"float, float"
 Function,-,hypotl,long double,"long double, long double"
@@ -2555,6 +2556,7 @@ Function,-,rfal_platform_spi_acquire,void,
 Function,-,rfal_platform_spi_release,void,
 Function,-,rfal_set_callback_context,void,void*
 Function,-,rfal_set_state_changed_callback,void,RfalStateChangedCallback
+Function,+,rgb2hsv,HsvColor,RgbColor
 Function,+,rgb_backlight_get_color_count,uint8_t,
 Function,+,rgb_backlight_get_color_text,const char*,uint8_t
 Function,+,rgb_backlight_get_settings,RGBBacklightSettings*,
diff --git a/lib/toolbox/colors.c b/lib/toolbox/colors.c
new file mode 100644
index 000000000..0de9ecf85
--- /dev/null
+++ b/lib/toolbox/colors.c
@@ -0,0 +1,87 @@
+// https://stackoverflow.com/a/14733008
+
+#include "colors.h"
+
+RgbColor hsv2rgb(HsvColor hsv) {
+    RgbColor rgb;
+    uint8_t region, remainder, p, q, t;
+
+    if(hsv.s == 0) {
+        rgb.r = hsv.v;
+        rgb.g = hsv.v;
+        rgb.b = hsv.v;
+        return rgb;
+    }
+
+    region = hsv.h / 43;
+    remainder = (hsv.h - (region * 43)) * 6;
+
+    p = (hsv.v * (255 - hsv.s)) >> 8;
+    q = (hsv.v * (255 - ((hsv.s * remainder) >> 8))) >> 8;
+    t = (hsv.v * (255 - ((hsv.s * (255 - remainder)) >> 8))) >> 8;
+
+    switch(region) {
+    case 0:
+        rgb.r = hsv.v;
+        rgb.g = t;
+        rgb.b = p;
+        break;
+    case 1:
+        rgb.r = q;
+        rgb.g = hsv.v;
+        rgb.b = p;
+        break;
+    case 2:
+        rgb.r = p;
+        rgb.g = hsv.v;
+        rgb.b = t;
+        break;
+    case 3:
+        rgb.r = p;
+        rgb.g = q;
+        rgb.b = hsv.v;
+        break;
+    case 4:
+        rgb.r = t;
+        rgb.g = p;
+        rgb.b = hsv.v;
+        break;
+    default:
+        rgb.r = hsv.v;
+        rgb.g = p;
+        rgb.b = q;
+        break;
+    }
+
+    return rgb;
+}
+
+HsvColor rgb2hsv(RgbColor rgb) {
+    HsvColor hsv;
+    uint8_t rgbMin, rgbMax;
+
+    rgbMin = rgb.r < rgb.g ? (rgb.r < rgb.b ? rgb.r : rgb.b) : (rgb.g < rgb.b ? rgb.g : rgb.b);
+    rgbMax = rgb.r > rgb.g ? (rgb.r > rgb.b ? rgb.r : rgb.b) : (rgb.g > rgb.b ? rgb.g : rgb.b);
+
+    hsv.v = rgbMax;
+    if(hsv.v == 0) {
+        hsv.h = 0;
+        hsv.s = 0;
+        return hsv;
+    }
+
+    hsv.s = 255 * ((long)rgbMax - (long)rgbMin) / hsv.v;
+    if(hsv.s == 0) {
+        hsv.h = 0;
+        return hsv;
+    }
+
+    if(rgbMax == rgb.r)
+        hsv.h = 0 + 43 * (rgb.g - rgb.b) / (rgbMax - rgbMin);
+    else if(rgbMax == rgb.g)
+        hsv.h = 85 + 43 * (rgb.b - rgb.r) / (rgbMax - rgbMin);
+    else
+        hsv.h = 171 + 43 * (rgb.r - rgb.g) / (rgbMax - rgbMin);
+
+    return hsv;
+}
diff --git a/lib/toolbox/colors.h b/lib/toolbox/colors.h
new file mode 100644
index 000000000..8fc930dbf
--- /dev/null
+++ b/lib/toolbox/colors.h
@@ -0,0 +1,27 @@
+#pragma once
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct RgbColor {
+    uint8_t r;
+    uint8_t g;
+    uint8_t b;
+} RgbColor;
+
+typedef struct HsvColor {
+    uint8_t h;
+    uint8_t s;
+    uint8_t v;
+} HsvColor;
+
+RgbColor hsv2rgb(HsvColor hsv);
+
+HsvColor rgb2hsv(RgbColor rgb);
+
+#ifdef __cplusplus
+}
+#endif