What's the easiest way to light a sine wave of a specific RGB or

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1

What’s the easiest way to light a sine wave of a specific RGB or HSV color? I like how this looks but instead of controlling red, blue and green individually I want to have a specific color moving.

void plas3() {

wave1 +=2;
wave2 +=1;
wave3 -=3;
for (int k=0; k<NUM_LEDS; k++) {
	leds[k].r = qsub(sin8(20*k + wave1), 80);									 // Another fixed frequency, variable phase sine wave with lowered level
	leds[k].g = qsub(cos8(25*k + wave2), 80);									 // A fixed frequency, variable phase sine wave with lowered level
	leds[k].b = qsub(sin8(22*k + wave3), 80);									 // A fixed frequency, variable phase sine wave with lowered level
}
LEDS.show();
delay(thisdelay);

}

2

Paging @Andrew_Tuline … :wink:

3

I wrote that pre-palette days. You have a few options here and since you’re getting an 8 bit value, you could use HSV and say:

uint8_t val = qsub(sin8(20*k + wave1), 80);
leds[k] = CHSV(val, 255, 255);

You could also use palettes (which is what I do these days) and:

uint8_t val = qsub(sin8(20*k + wave1), 80);
leds[i] = ColorFromPalette(currentPalette, val, brightness, currentBlending);

So, I’d just play around and try different things. Also, don’t forget to read colorutils.h and lib8tion.h for more fun with functions.

4

Here’s another example to give you ideas.

5

Mark’s got some great examples on github.

6

Had this saved in a notes file also. Change beatsin16 to other wave functions to experiment.

// Moving “Cylon” dot with fading motion blurred trails:
fadeToBlackBy( leds, NUM_LEDS, 20); //fade by 7.8% (20/256th)
int pos = beatsin16(13,0,NUM_LEDS);
leds[pos] = CRGB::Blue;

And here’s a sin cheatsheet which always makes it easier to remember what to adjust.

[Album] Imgur

7

Here’s my notes file:

http://tuline.com/some-fastled-notes/

8

anyone got a good site/page that lays out sine waves as they apply to this sort of thing in layman’s terms. I’ve had a hard time wrapping my head around it and what it actually does and I get the feeling older projects of mine could have benefitted from using the math.