What would be the fastest way to increment the hue value of a CRGB

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1

What would be the fastest way to increment the hue value of a CRGB class? Thanks!

2

I believe that’s. . .

leds[i].g++;

for green. Then there’s r and b.

3

Right, I can adjust each channel separately that way but I’m looking for a way to adjust all three channels in a hue advancement way.

4

I believe you can’t directly manipulate the hue of a CRGB. You’d have to convert it to HSV first. There is a function called rgb2hsv but the results are an approximation (for math reasons) and sketchy to use consistently. You can find the explanation in the file https://github.com/FastLED/FastLED/blob/master/hsv2rgb.h (Search for rgb2hsv).

If you could store your colors in CHSV from the beginning, it would make your life easier.

5

Can you work with HSV instead? Seems that would be much more straight forward to how you’re wanting to make a color adjustment.

Can you give us a bit more context?

6

It is very easy to switch if you start with HSV…the library does the work automatically, even for an entire palette. For instance:

// switch palette

  if(ipal == 0 ) {currentRGBPalette = PartyColors_p ;}
  else if( ipal == 1) {currentRGBPalette = BluesHSV_p ;}
    else if ( ipal == 2 ) {currentRGBPalette = RedsHSV_p ;}
      else if( ipal == 3 ) {currentRGBPalette = GreensHSV_p ;}
  
  for(int ic = 0 ; ic < 16 ; ic++ ) {

// we take advantage of the library’s auto conversion of color space from
// HSV to RGB and use a CRGB variable for the color, even though we are getting the color from
// an HSV palette
CRGB c = currentRGBPalette[ic] ;

This works just fine. I wrote it so that I could use both HSV hue control and color blending.