Displays a gradient between two colors
Dependencies: PixelArray WS2812 mbed
main.cpp
- Committer:
- theros
- Date:
- 2017-03-12
- Revision:
- 0:3bb97062a703
File content as of revision 0:3bb97062a703:
#include "mbed.h" #include "WS2812.h" #include "PixelArray.h" #define WS2812_BUF 77 //number of LEDs in the array #define NUM_COLORS 2 //number of colors to store in the array DigitalOut usrLed(LED1); PixelArray px(WS2812_BUF); // See the program page for information on the timing numbers WS2812 ws(D9, WS2812_BUF, 6,17,9,14); //nucleo-f411re int color_set(uint8_t red,uint8_t green, uint8_t blue) { return ((red<<16) + (green<<8) + blue); } // 0 <= stepNumber <= lastStepNumber int interpolate(int startValue, int endValue, int stepNumber, int lastStepNumber) { return (endValue - startValue) * stepNumber / lastStepNumber + startValue; } int main() { uint8_t ir = 0; uint8_t ig = 0; uint8_t ib = 0; ws.useII(WS2812::PER_PIXEL); // use per-pixel intensity scaling // set up the colours we want to draw with int colorbuf[NUM_COLORS] = {0xff0000,0x0000ff}; //get starting RGB components for interpolation std::size_t c1 = colorbuf[0]; std::size_t r1 = (c1 & 0xff0000) >> 16; std::size_t g1 = (c1 & 0x00ff00) >> 8; std::size_t b1 = (c1 & 0x0000ff); //get ending RGB components for interpolation std::size_t c2 = colorbuf[1]; std::size_t r2 = (c2 & 0xff0000) >> 16; std::size_t g2 = (c2 & 0x00ff00) >> 8; std::size_t b2 = (c2 & 0x0000ff); for (int i = 0; i <= WS2812_BUF; i++) { ir = interpolate(r1, r2, i, WS2812_BUF); ig = interpolate(g1, g2, i, WS2812_BUF); ib = interpolate(b1, b2, i, WS2812_BUF); //write the color value for each pixel px.Set(i, color_set(ir,ig,ib)); //write the II value for each pixel px.SetI(i, 32); } for (int i = WS2812_BUF; i >= 0; i--) { ws.write(px.getBuf()); } usrLed = 1; }