LED Strip Pattern Collection

Note: Some of these may be written specifically for octows2811, neopixel or fastSPI, but it's usually easy to port between them (change the show and set color functions).

Random Twinkle

// number, twinkle color, background color, delay
// twinkleRand(5,strip.Color(255,255,255),strip.Color(255, 0, 100),90);

// twinkle random number of pixels
void twinkleRand(int num,uint32_t c,uint32_t bg,int wait) {
	// set background
	 stripSet(bg,0);
	 // for each num
	 for (int i=0; i<num; i++) {
	   strip.setPixelColor(random(strip.numPixels()),c);
	 }
	strip.show();
	delay(wait);
}

Set All Pixels Quickly

// quickly set the entire strip a color
void stripSet(uint32_t c, uint8_t wait) {
  for(uint16_t i=0; i<strip.numPixels(); i++) {
      strip.setPixelColor(i, c);
  }
  // move the show outside the loop
  strip.show();
  delay(wait);
}

Simple Wave

 // very simple wave: velocity, cycles,delay between frames
 // simpleWave(0.03,5,10);
void simpleWave(float rate,int cycles, int wait) {
   float pos=0.0;
  // cycle through x times
  for(int x=0; x<(strip.numPixels()*cycles); x++)
  {
      pos = pos+rate;
      for(int i=0; i<strip.numPixels(); i++) {
        // sine wave, 3 offset waves make a rainbow!
        float level = sin(i+pos) * 127 + 128;
        // set color level 
        strip.setPixelColor(i,(int)level,0,0);
      }
         strip.show();
         delay(wait);
  }
}  

HSV to RGB

Really useful function returns RGB values from Hue Saturation Brightness! Adapted from teldredge's FAST_SPI LED FX EXAMPLES for use in the NeoPixel lib

void HSVtoRGB(int hue, int sat, int val,int *colors) {
  	int r, g, b, base;

	// hue: 0-359, sat: 0-255, val (lightness): 0-255


	if (sat == 0) { // Achromatic color (gray).
		colors[0]=val;
		colors[1]=val;
		colors[2]=val;
	} else  {
		base = ((255 - sat) * val)>>8;
		switch(hue/60) {
			case 0:
				colors[0] = val;
				colors[1] = (((val-base)*hue)/60)+base;
				colors[2] = base;
				break;
			case 1:
				colors[0] = (((val-base)*(60-(hue%60)))/60)+base;
				colors[1] = val;
				colors[2] = base;
				break;
			case 2:
				colors[0] = base;
				colors[1] = val;
				colors[2] = (((val-base)*(hue%60))/60)+base;
				break;
			case 3:
				colors[0] = base;
				colors[1] = (((val-base)*(60-(hue%60)))/60)+base;
				colors[2] = val;
				break;
			case 4:
				colors[0] = (((val-base)*(hue%60))/60)+base;
				colors[1] = base;
				colors[2] = val;
				break;
			case 5:
				colors[0] = val;
				colors[1] = base;
				colors[2] = (((val-base)*(60-(hue%60)))/60)+base;
				break;
		}
		
	}
}