oled-rpi-i2c-bus-async/tests/drawRGBAImage.js

Asynchronous NodeJS module for controlling oled devices on the Raspbery Pi (including the SSD1306 and SH1106 OLED screens)

import i2c from 'i2c-bus';
import SSD1306 from '../oled.mjs';
import path from 'path';
import fs from 'fs';
import { PNG } from 'pngjs';

const dirresources = path.join(__dirname, '../..', 'resources/');
const HEIGHT = 64;
const WIDTH = 128;
const opts = {
	width: WIDTH,
	height: HEIGHT,
	address: 0x3c,
	bus: 3,
	driver: 'SH1106',
};

const initializeDisplay = async () => {
	try {
		const i2cBus = await i2c.openPromisified(opts.bus || 3);
		const oled = new SSD1306(i2cBus, opts);

		await oled.clearDisplay(true);
		const piLogo = 'rpi-frambuesa.png';
		let image;
		if (typeof piLogo === 'string' && !piLogo.includes('/')) {
			image = dirresources + piLogo;
		} else {
			console.log('Invalid image filename');
			process.exit(1);
		}
		if (!fs.statSync(image).isFile()) {
			console.log('file ' + image + ' not exist.');
			process.exit(1);
		}

		fs.createReadStream(image)
			.pipe(new PNG({ filterType: 4 }))
			.on('parsed', async function () {
				await oled.drawRGBAImage(
					this,
					Math.floor((WIDTH - this.width) / 2), // x-pos center width
					Math.floor((HEIGHT - this.height) / 2), // y-pos center height
					true
				);
			});
	} catch (err) {
		console.log(err.message);
		process.exit(1);
	}
};

initializeDisplay();