Fix color conversion bug lighting-example (#27065)

* Fix color conversion bug lighting-example This commit fixes the bug of issue #27063. The used code is a copy of `[MATTERROOT]/examples/lighting-app/genio/src/ColorFormat.cpp` * Restyled by clang-format --------- Co-authored-by: Restyled.io <[email protected]>
project-chip · Sep 22, 2023 · 1106434 · 1106434
1 parent f22de5b
commit 1106434
Showing 1 changed file with 38 additions and 36 deletions.
diff --git a/examples/lighting-app/lighting-common/src/ColorFormat.cpp b/examples/lighting-app/lighting-common/src/ColorFormat.cpp
@@ -27,44 +27,46 @@ RgbColor_t HsvToRgb(HsvColor_t hsv)
 {
     RgbColor_t rgb;
 
-    uint16_t i       = hsv.h / 60;
-    uint16_t rgb_max = hsv.v;
-    uint16_t rgb_min = (uint16_t)(rgb_max * (100 - hsv.s)) / 100;
-    uint16_t diff    = hsv.h % 60;
-    uint16_t rgb_adj = (uint16_t)((rgb_max - rgb_min) * diff) / 60;
+    uint8_t region, p, q, t;
+    uint32_t h, s, v, remainder;
 
-    switch (i)
+    if (hsv.s == 0)
     {
-    case 0:
-        rgb.r = (uint8_t) rgb_max;
-        rgb.g = (uint8_t)(rgb_min + rgb_adj);
-        rgb.b = (uint8_t) rgb_min;
-        break;
-    case 1:
-        rgb.r = (uint8_t)(rgb_max - rgb_adj);
-        rgb.g = (uint8_t) rgb_max;
-        rgb.b = (uint8_t) rgb_min;
-        break;
-    case 2:
-        rgb.r = (uint8_t) rgb_min;
-        rgb.g = (uint8_t) rgb_max;
-        rgb.b = (uint8_t)(rgb_min + rgb_adj);
-        break;
-    case 3:
-        rgb.r = (uint8_t) rgb_min;
-        rgb.g = (uint8_t)(rgb_max - rgb_adj);
-        rgb.b = (uint8_t) rgb_max;
-        break;
-    case 4:
-        rgb.r = (uint8_t)(rgb_min + rgb_adj);
-        rgb.g = (uint8_t) rgb_min;
-        rgb.b = (uint8_t) rgb_max;
-        break;
-    default:
-        rgb.r = (uint8_t) rgb_max;
-        rgb.g = (uint8_t) rgb_min;
-        rgb.b = (uint8_t)(rgb_max - rgb_adj);
-        break;
+        rgb.r = rgb.g = rgb.b = hsv.v;
+    }
+    else
+    {
+        h = hsv.h;
+        s = hsv.s;
+        v = hsv.v;
+
+        region    = h / 43;
+        remainder = (h - (region * 43)) * 6;
+        p         = (v * (255 - s)) >> 8;
+        q         = (v * (255 - ((s * remainder) >> 8))) >> 8;
+        t         = (v * (255 - ((s * (255 - remainder)) >> 8))) >> 8;
+        switch (region)
+        {
+        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;
+        case 5:
+        default:
+            rgb.r = v, rgb.g = p, rgb.b = q;
+            break;
+        }
     }
 
     return rgb;