File content as of revision 4:c8515fbd2e44:

#include "mbed.h" // remove line if not using mbed

#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include "nrf_delay.h"
#include "nrf_gpio.h"
#include "neopixel.h"

// Input a value 0 to 255 to get a color value.
// The colours are a transition r - g - b - back to r.
uint32_t Wheel(uint8_t WheelPos, neopixel_strip_t m_strip, uint8_t led_to_enable) {
  WheelPos = 255 - WheelPos;
  if(WheelPos < 85) {
    return neopixel_set_color(&m_strip, led_to_enable, 255 - WheelPos * 3, 0, WheelPos * 3);
  }
  if(WheelPos < 170) {
    WheelPos -= 85;
    return neopixel_set_color(&m_strip, 0, led_to_enable, WheelPos * 3, 255 - WheelPos * 3);
  }
  WheelPos -= 170;
  return neopixel_set_color(&m_strip, led_to_enable, WheelPos * 3, 255 - WheelPos * 3, 0);
}

void rainbowCycle(int delay, uint8_t numLEDs, neopixel_strip_t m_strip) {
  uint16_t i, j;
  uint32_t ret;

  for(j=0; j<256*5; j++) { // 5 cycles of all colors on wheel
    for(i=0; i< numLEDs; i++) {
      //neopixel_set_color(&m_strip, i, red, green, blue);
      //strip.setPixelColor(i, Wheel(((i * 256 / strip.numPixels()) + j) & 255));
      ret = Wheel(i, m_strip, ((i * 256 / numLEDs) + j & 255));
    }
    neopixel_show(&m_strip);
    wait_ms(delay);
  }
}

void candyChase(int delay, uint8_t numLEDs, neopixel_strip_t m_strip) {
  for (int j=0; j<10; j++) {  //do 10 cycles of chasing
    for (int q=0; q < 3; q++) {
      for (uint16_t i=0; i < numLEDs; i++) {
        neopixel_set_color(&m_strip, i, 255,255,255);    //turn every pixel white
      }
      for (uint16_t i=0; i < numLEDs; i=i+3) {
        neopixel_set_color(&m_strip, i, 255,0,0);    //turn every third pixel red
      }
      neopixel_show(&m_strip);

      wait_ms(delay);

      for (uint16_t i=0; i < numLEDs; i=i+3) {
        neopixel_set_color(&m_strip, i, 0,0,0);        //turn every third pixel off
      }
    }
  }
}

void snowflakes(int delay, uint8_t numLEDs, neopixel_strip_t m_strip) {

    // Setup the pixel array
    int pixel[numLEDs];
    for(int p=0; p<numLEDs; p++)
      pixel[p] = rand()%255; 
    

    // Run some snowflake cycles
    for (int j=0; j<20; j++) {
        // Every five cycles, light a new pixel
        if((j%5)==0)
          neopixel_set_color(&m_strip, rand()%numLEDs, 255,255,255);
        
        // Dim all pixels by 10
        for(int p=0; p<numLEDs; p++){
          neopixel_set_color(&m_strip, p, pixel[p],pixel[p],pixel[p] );
          pixel[p] =  pixel[p] - 10;
        }
        neopixel_show(&m_strip);
        wait_ms(delay);
    }
}

void iceflakes(int delay, uint8_t numLEDs, neopixel_strip_t m_strip) {

    // Setup the pixel array
    int pixel[numLEDs];
    for(int p=0; p<numLEDs; p++)
      pixel[p] = rand()%255; 
    
    // Run some snowflake cycles
    for (int j=0; j<20; j++) {
        // Every five cycles, light a new pixel
        if((j%5)==0)
          neopixel_set_color(&m_strip, rand()%numLEDs, 0,0,255);
        
        // Dim all pixels by 10
        for(int p=0; p<numLEDs; p++){
          neopixel_set_color(&m_strip, p, 0,0,pixel[p] );
          pixel[p] =  pixel[p] - 10;
        }
       neopixel_show(&m_strip);
       wait_ms(delay);
    }
}