![]() The speedValue is in milliseconds and is used from the start to the finish of the fade. 0 is the LED completely off, 255 is the LED Completely on and all values between is a PWM percent. These Rvalue, Gvalue and Bvalue Byte variables are the values between 0 and 255. Rvalue, Gvalue and Bvalue are used to set the RGB colour and speedValue is used to set the fade speed. This function is used to fade from the current set colour to a RGB colour at a speed. void fadeTo(byte Rvalue,byte Gvalue,byte Bvalue,unsigned long speedValue) If the FadeValue is set to be 0.5 at 1000 speed the fade would continue from 50%. This Functions sets the speed of fades and the speed of colour functions. These RGB Byte variables are the values between 0 and 255. Rvalue, Gvalue and Bvalue are used to set the RGB colour. SET void set(byte Rvalue,byte Gvalue,byte Bvalue) pinR, pinG and pinB is where the PWM pin numbers are placed. ![]() This is the setup for the class, this is where the pins are declared for the RGB LED. You can also write CHSV objects into the CRGB array and have the translation occur as necessary.Functions SETUP RGB_LED(byte pinR,byte pinG,byte pinB) CHSV objects have to be converted to CRGB objects before they can be written out. There's two main pixel types in the library - the CRGB class and the CHSV class. In any case there will be rounding errors, and thus discontinuities in the hue.ĭefining a color as CHSV and manually changing the V value for fading it wouldn't improve the result, as CHSV values are internally converted to CRGB. FastLED will take care of fading it out in the most accurate way, no matter what if the LED has been assigned using CHSV or CRGB. The best way to progressively fade to black the whole LED strip, or an individual one, is to repeatedly call the fadeToBlackBy method in the main loop. ![]() It's not FastLED implementation, it's just a limitation of integer math and the relatively low resolution of current RGB LEDs, having "only" 8-bit per channel. The downside is they aren't supported by FastLED yet, as far as I know. Some LEDs offer 16-bit per channel color resolution (and in some cases a color-independent brightness channel too) and that alone would make transitions much smoother and greatly reduce the need for temporal dithering. However, temporal dithering would introduce other artifacts which might be visible in some cases. Synchronously driven LEDs like APA102C or HD107S would definitely be more effective as they can be driven at much higher data rate (20/40MHz) than more conventional asynchronous WS2812B LEDs (800kHz). The only way for increasing the apparent color resolution is to use temporal dithering, but to be effective it requires very high frame rates. In the following example the hue jump happens twice (at first and second transitions): In fact, and are two different colors, as the first one has some green, the second one has no green at all. In this case it happens at the second transition. => => => => īut if the initial color is there will be a "hue jump" at some point, when the original proportion between R, G and B is lost. In this case your fading sequence would respect the original hue, as the proportion between R, G and B is kept (R and G always have the same value): Say you have a color with RGB values, and your fading algorithm divides the value by 2, taking the integer part of the result. ![]() ![]() The problem is that all RGB LEDs are driven using a finite set of values (typically integers between 0 and 255 per channel) and no matter what the fading algorithm, at some point there will be discontinuities in the hue due to rounding errors. That wouldn't solve the issue as CHSV values will need to be translated to 8-bit RGB at some point before they hit the LEDs. ![]()
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