color_fade optimizations

* removed unnecessary conditions
* optimized bit-shifting logic
* use uint16_t for colors, to prevent the compiler from using 64bit integer

Author: softhack007

wled00/colors.cpp

@@ -84,25 +84,27 @@ IRAM_ATTR_YN __attribute__((hot)) uint32_t color_fade(uint32_t c1, uint8_t amoun
   if (amount == 255) return c1; // WLEDMM small optimization - plus it avoids over-fading in "video" mode
   if (amount == 0) return 0; // WLEDMM shortcut
 
-  uint32_t scaledcolor; // color order is: W R G B from MSB to LSB
-  uint32_t r = R(c1);
-  uint32_t g = G(c1);
-  uint32_t b = B(c1);
-  uint32_t w = W(c1);
+  uint32_t scaledcolor = 0; // color order is: W R G B from MSB to LSB
+  uint16_t w = W(c1);    // WLEDMM 16bit to make sure the compiler uses 32bit (not 64bit) for the math
+  uint16_t r = R(c1);
+  uint16_t g = G(c1);
+  uint16_t b = B(c1);
   if (video)  {
-    uint32_t scale = amount; // 32bit for faster calculation
-    scaledcolor = (((r * scale) >> 8) << 16) + ((r && scale) ? 1 : 0);
-    scaledcolor |= (((g * scale) >> 8) << 8) + ((g && scale) ? 1 : 0);
-    scaledcolor |= ((b * scale) >> 8) + ((b && scale) ? 1 : 0);
-    if (w>0) scaledcolor |= (((w * scale) >> 8) << 24) + ((scale) ? 1 : 0);  // WLEDMM small speedup when no white channel
+    uint16_t scale = amount; // 32bit for faster calculation
+    // bugfix: doing "+1" after shifting is obviously wrong
+    // optimization: ((r && scale) ? 1 : 0) can be simplified to "if (r > 0) +1" ; if we arive here, then scale != 0 and scale < 255
+    if (w>0) scaledcolor |= (((w * scale) >> 8) +1) << 24;  // WLEDMM small speedup when no white channel
+    if (r>0) scaledcolor |= (((r * scale) >> 8) +1) << 16;
+    if (g>0) scaledcolor |= (((g * scale) >> 8) +1) << 8;
+    if (b>0) scaledcolor |=  ((b * scale) >> 8) +1;
     return scaledcolor;
   }
   else  {
-    uint32_t scale = 1 + amount;
-    scaledcolor = ((r * scale) >> 8) << 16;
-    scaledcolor |= ((g * scale) >> 8) << 8;
-    scaledcolor |= (b * scale) >> 8;
+    uint16_t scale = 1 + amount;
     if (w>0) scaledcolor |= ((w * scale) >> 8) << 24;                              // WLEDMM small speedup when no white channel
+    scaledcolor |= ((r * scale) >> 8) << 16;
+    scaledcolor |= (g * scale) & 0x0000FF00;                                       // WLEDMM faster than right-left shift "" >>8 ) <<8"
+    scaledcolor |= (b * scale) >> 8;
     return scaledcolor;
   }
 }

wled00/wled.h

@@ -8,7 +8,7 @@
  */
 
 // version code in format yymmddb (b = daily build)
-#define VERSION 2411140
+#define VERSION 2411150
 
 // WLEDMM  - you can check for this define in usermods, to only enabled WLEDMM specific code in the "right" fork. Its not defined in AC WLED.
 #define _MoonModules_WLED_