From 8067f1f70c9c773b60b4b4ccf376488052209fa0 Mon Sep 17 00:00:00 2001
From: Frank <91616163+softhack007@users.noreply.github.com>
Date: Mon, 20 Oct 2025 21:49:09 +0200
Subject: [PATCH] bus.setPicelColor optimization: move colorBalanceFromKelvin
 into busmanager.cpp

colorBalanceFromKelvin() is only called from inside bus_manager.cpp, so we can help the compiler optimize by making it a local (static) fuction
---
 wled00/bus_manager.cpp | 18 ++++++++++++++++++
 wled00/colors.cpp      |  3 +++
 wled00/fcn_declare.h   |  2 +-
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/wled00/bus_manager.cpp b/wled00/bus_manager.cpp
index e4e70507..73072e97 100644
--- a/wled00/bus_manager.cpp
+++ b/wled00/bus_manager.cpp
@@ -79,6 +79,24 @@ uint8_t realtimeBroadcast(uint8_t type, IPAddress client, uint16_t length, byte
 #include "wled.h"
 #endif
 
+// WLEDMM moved here (from colors.cpp) for better optimization
+static inline uint32_t __attribute__((hot)) colorBalanceFromKelvin(uint16_t kelvin, uint32_t rgb)  // WLEDMM: IRAM_ATTR removed, inline for speed
+{
+  //remember so that slow colorKtoRGB() doesn't have to run for every setPixelColor()
+  static byte correctionRGB[4] = {255,255,255,0};               // default to neutral
+  static uint16_t lastKelvin = 0;
+  if (lastKelvin != kelvin) {
+    colorKtoRGB(kelvin, correctionRGB);  // convert Kelvin to RGB (slow)
+    lastKelvin = kelvin;
+  }
+  byte rgbw[4];
+  rgbw[0] = ((uint_fast16_t) correctionRGB[0] * R(rgb)) /255; // correct R //WLEDMM changed to fast type
+  rgbw[1] = ((uint_fast16_t) correctionRGB[1] * G(rgb)) /255; // correct G
+  rgbw[2] = ((uint_fast16_t) correctionRGB[2] * B(rgb)) /255; // correct B
+  rgbw[3] =                                W(rgb);
+  return RGBW32(rgbw[0],rgbw[1],rgbw[2],rgbw[3]);
+}
+
 
 void ColorOrderMap::add(uint16_t start, uint16_t len, uint8_t colorOrder) {
   if (_count >= WLED_MAX_COLOR_ORDER_MAPPINGS) {
diff --git a/wled00/colors.cpp b/wled00/colors.cpp
index 37241959..8e72d46b 100644
--- a/wled00/colors.cpp
+++ b/wled00/colors.cpp
@@ -310,6 +310,8 @@ static float maxf (float v, float w)  // WLEDMM better use standard library fmax
 
 // adjust RGB values based on color temperature in K (range [2800-10200]) (https://en.wikipedia.org/wiki/Color_balance)
 // called from bus manager when color correction is enabled!
+#if 0
+// WLEDMM moved into bus_manager.cpp for better optimization
 uint32_t __attribute__((hot)) IRAM_ATTR_YN colorBalanceFromKelvin(uint16_t kelvin, uint32_t rgb)  // WLEDMM: IRAM_ATTR_YN
 {
   //remember so that slow colorKtoRGB() doesn't have to run for every setPixelColor()
@@ -324,6 +326,7 @@ uint32_t __attribute__((hot)) IRAM_ATTR_YN colorBalanceFromKelvin(uint16_t kelvi
   rgbw[3] =                                W(rgb);
   return RGBW32(rgbw[0],rgbw[1],rgbw[2],rgbw[3]);
 }
+#endif
 
 //approximates a Kelvin color temperature from an RGB color.
 //this does no check for the "whiteness" of the color,
diff --git a/wled00/fcn_declare.h b/wled00/fcn_declare.h
index 1a9247a2..188c10ee 100644
--- a/wled00/fcn_declare.h
+++ b/wled00/fcn_declare.h
@@ -66,7 +66,7 @@ void colorXYtoRGB(float x, float y, byte* rgb); // only defined if huesync disab
 void colorRGBtoXY(byte* rgb, float* xy); // only defined if huesync disabled TODO
 void colorFromDecOrHexString(byte* rgb, char* in);
 bool colorFromHexString(byte* rgb, const char* in);
-uint32_t colorBalanceFromKelvin(uint16_t kelvin, uint32_t rgb);
+//uint32_t colorBalanceFromKelvin(uint16_t kelvin, uint32_t rgb);                             // WLEDMM function moved into bus_manager.cpp for better optimization
 uint16_t __attribute__((const)) approximateKelvinFromRGB(uint32_t rgb);                       // WLEDMM: added attribute const
 void setRandomColor(byte* rgb);
 uint8_t gamma8_cal(uint8_t b, float gamma);