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PixelBuffer

A 1D color vector to support color manipulation of LED strips. All colors are 24bit RGB colors.

The pixel buffer is typically accessed through a Led client.

import { Led } from "@devicescript/core"
import "@devicescript/runtime"

const led = new Led()
const pixels = await led.buffer()

It can also be allocated using pixelBuffer.

import { PixelBuffer } from "@devicescript/runtime"

const pixels = PixelBuffer.alloc(32)

Usage​

at, setAt​

Indexing functions similar to Array.at, they allow to set color of individual LEDs and support negative indices.

const c0 = pixels.at(0)
pixels.setAt(1, c0)

clear​

Clears all colors to #000000.

pixels.clear()

view​

Creates a aliased range view of the buffer so that you can apply operations on a subset of the colors.

const view = pixels.view(5, 10)
view.clear()

correctGamma​

Applies gamma correction to compensate LED and eye perception

pixels.correctGamma()

rotate​

Shifts the colors in the buffer by the given offset. Use a negative offset to shift right.

pixels.rotate(-1)

Helpers​

Here are a few helpers built for PixelBuffer, but many other could be added!

fillSolid​

This helper function asigns the given color to the entire range.

import { Led } from "@devicescript/core"
import { fillSolid } from "@devicescript/runtime"

const led = new Led()
const pixels = await led.buffer()

fillSolid(pixels, 0x00_ff_00)

await led.show()

fillRainbow​

Fills the buffer by interpolating the hue of hsv colors.

import { Led } from "@devicescript/core"
import { fillRainbow } from "@devicescript/runtime"

const led = new Led()
const pixels = await led.buffer()

fillRainbow(pixels)

await led.show()

By default, the helper interpolates between 0 and 0xff, but this can be changed with optional parameters.

fillGradient​

Fills with a linear interpolation of two colors accross the RGB space.

import { Led } from "@devicescript/core"
import { fillGradient } from "@devicescript/runtime"

const led = new Led()
const pixels = await led.buffer()

fillGradient(pixels, 0x00_ff_00, 0x00_00_ff, { circular: true })

await led.show()

fillPalette​

Fills by interpolating the colors of a palette.

import { Led } from "@devicescript/core"
import { Palette } from "@devicescript/graphics"
import { fillPalette } from "@devicescript/runtime"

const led = new Led()
const pixels = await led.buffer()
const palette = Palette.arcade()

fillPalette(pixels, palette)

await led.show()

fillBarGraph​

A tiny bar chart engine to render on a value on a LED strip

import { Led } from "@devicescript/core"
import { fillBarGraph } from "@devicescript/runtime"

const led = new Led()
const pixels = await led.buffer()

const current = 25
const max = 100

fillBarGraph(pixels, current, max)

await led.show()