pxt-neoanim/README.md

1.6 KiB

neoanim

A neopixel animation based on bitmaps

Animation Sheet

Creates an animation from a pre-rendered set of frames

light.animationSheet(null, 50)

Parameters

  • buffer, the buffer containing the data (more below)
  • interval, the time in milliseconds between each frame

Buffer format

The bitmap format should be specified as follows. All values are little endian.

  • magic number 0x2e0a21, 4 bytes
  • palette size, 1 byte (npalette)
  • reserved padding, 1 byte
  • palette, npalette x 24bit RGB colors
  • frames, nleds x number of frames. A contiguous sequence of palette color indices.

Example

Generating your own animation

The following sample generates a buffer and uses it to create the animation.

const strip = light.pixels;
const nleds = strip.length();
const ncolors = 3;
const nframes = 10;
const sheet = pins.createBuffer(6 + ncolors * 3 + nleds * nframes);
const palette = sheet.slice(6, ncolors * 3);
const frames = sheet.slice(6 + palette.length);

// magic number
sheet.setNumber(0, NumberFormat.UInt32LE, 0x2e0a21);
// palette
sheet[4] = ncolors;
palette[0] = 0xff; // red
palette[4] = 0xff; // green
palette[8] = 0xff; // blue
// filing up colors
let k = 0;
for (let i = 0; i < nleds; ++i) {
    for (let j = 0; j < nframes; ++j) {
        frames[k++] = i + j % ncolors;
    }
}
let anim = light.animationSheet(sheet, 50);

loops.forever(() => {
    strip.showAnimation(anim, 10000);
})

License

MIT

Supported targets

  • for PXT/ adafruit (The metadata above is needed for package search.)