81 lines
2.0 KiB
JavaScript
81 lines
2.0 KiB
JavaScript
const dgram = require('dgram');
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const host = process.argv[2];
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const port = parseInt(process.argv[3] || '4210', 10);
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const pixels = parseInt(process.argv[4] || '64', 10);
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const intervalMs = parseInt(process.argv[5] || '30', 10);
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if (!host) {
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console.error('Usage: node bouncing-ball.js <device-ip> [port] [pixels] [interval-ms]');
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process.exit(1);
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}
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const socket = dgram.createSocket('udp4');
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const isBroadcast = host === '255.255.255.255' || host.endsWith('.255');
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let position = Math.random() * (pixels - 1);
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let velocity = randomVelocity();
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function randomVelocity() {
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const min = 0.15;
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const max = 0.4;
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const sign = Math.random() < 0.5 ? -1 : 1;
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return (min + Math.random() * (max - min)) * sign;
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}
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function rebound(sign) {
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velocity = randomVelocity() * sign;
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}
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function mix(a, b, t) {
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return a + (b - a) * t;
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}
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function generateFrame() {
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const dt = intervalMs / 1000;
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position += velocity * dt * 60; // scale velocity to 60 FPS reference
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if (position < 0) {
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position = -position;
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rebound(1);
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} else if (position > pixels - 1) {
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position = (pixels - 1) - (position - (pixels - 1));
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rebound(-1);
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}
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const activeIndex = Math.max(0, Math.min(pixels - 1, Math.round(position)));
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let payload = 'RAW:';
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for (let i = 0; i < pixels; i++) {
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if (i === activeIndex) {
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payload += 'ff8000';
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continue;
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}
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const distance = Math.abs(i - position);
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const intensity = Math.max(0, 1 - distance);
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const green = Math.round(mix(20, 200, intensity)).toString(16).padStart(2, '0');
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const blue = Math.round(mix(40, 255, intensity)).toString(16).padStart(2, '0');
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payload += '00' + green + blue;
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}
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return payload;
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}
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function sendFrame() {
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const payload = generateFrame();
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const message = Buffer.from(payload, 'utf8');
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socket.send(message, port, host);
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}
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setInterval(sendFrame, intervalMs);
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if (isBroadcast) {
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socket.bind(() => {
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socket.setBroadcast(true);
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});
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}
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console.log(`Streaming bouncing ball pattern to ${host}:${port} with ${pixels} pixels (interval=${intervalMs}ms)`);
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