From fa0c46d5c7777289b03bc5dfb47eedb035b4c908 Mon Sep 17 00:00:00 2001
From: Victor Westerlund <victor.vesterlund@gmail.com>
Date: Tue, 26 Jan 2021 05:47:26 +0100
Subject: [PATCH] Working demo

Down on you knees!
---
 index.html                 |  4 +--
 js/main.js                 | 44 +++++++++++++++++++++---
 js/modules/ElectronGun.mjs | 31 +++++++++++++++++
 js/modules/Gun.mjs         | 24 -------------
 js/modules/Helper.mjs      |  4 +++
 js/modules/Raster.mjs      | 69 ++++++++++++++++++++++++++++----------
 js/modules/Screen.mjs      |  9 ++++-
 tapes/sample/header.json   | 10 ++++--
 8 files changed, 144 insertions(+), 51 deletions(-)
 create mode 100644 js/modules/ElectronGun.mjs
 delete mode 100644 js/modules/Gun.mjs
 create mode 100644 js/modules/Helper.mjs

diff --git a/index.html b/index.html
index cd094e5..0f88774 100644
--- a/index.html
+++ b/index.html
@@ -4,7 +4,7 @@
 	<meta charset="UTF-8">
 	<meta name="viewport" content="width=device-width, initial-scale=1.0">
 	<link rel="stylesheet" href="css/style.css">
-	<title>Cathode Ray</title>
+	<title>CRT</title>
 	<style>
 		:root {
 			/* Screen */
@@ -22,4 +22,4 @@
 	<div id="screen"></div>
 	<script src="js/main.js" type="module"></script>
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/js/main.js b/js/main.js
index e24cc37..4866f19 100644
--- a/js/main.js
+++ b/js/main.js
@@ -1,7 +1,43 @@
 import { FluorescentScreen } from "./modules/Screen.mjs";
-import { RasterScan } from "./modules/Gun.mjs";
+import { RasterScan } from "./modules/ElectronGun.mjs";
 
-const screen = new FluorescentScreen(document.getElementById("screen"));
+class CRT {
 
-const CRT = new RasterScan(screen.pixels);
-CRT.load("../../tapes/sample");
\ No newline at end of file
+	constructor(element) {
+		this.element = element;
+		this.initScreen();
+		this.raster = new RasterScan(this.screen.pixels);
+	}
+
+	async fetchJSON(url) {
+		const response = await fetch(url);
+		return response.json();
+	}
+
+	loadTape(ref) {
+		this.fetchJSON(ref + "/header.json").then(headers => {
+			// Reinitialize player with resolution from tape header
+			if(headers.resolution[0] !== this.element.clientWidth || headers.resolution[1] !== this.element.clientHeight) {
+				this.element.style.setProperty("width",headers.resolution[0] + "px");
+				this.element.style.setProperty("height",headers.resolution[1] + "px");
+				this.initScreen();
+				this.raster.pixels = this.screen.pixels;
+			}
+
+			this.raster.load(headers);
+		});
+	}
+
+	play() {
+		this.raster.playstate("play");
+	}
+
+	initScreen() {
+		this.screen = new FluorescentScreen(this.element);
+	}
+
+}
+
+window.video = new CRT(document.getElementById("screen"));
+window.video.loadTape("tapes/sample");
+window.video.play();
diff --git a/js/modules/ElectronGun.mjs b/js/modules/ElectronGun.mjs
new file mode 100644
index 0000000..2d9034c
--- /dev/null
+++ b/js/modules/ElectronGun.mjs
@@ -0,0 +1,31 @@
+export class RasterScan {
+
+	constructor(pixels) {
+		this.pixels = pixels;
+		this.signal = new Worker("./js/modules/Raster.mjs");
+
+		this.signal.addEventListener("message",event => {
+			this.fire(event.data);
+		});
+	}
+
+	fire(pixel) {
+		this.pixels[pixel.index].style.setProperty("background",pixel.color);
+		//this.pixels[data.pixel].style.setProperty("animation",`decay 10ms ${data.pixel} linear forwards`);
+	}
+
+	load(headers) {
+		this.signal.postMessage({
+			type: "headers",
+			payload: headers
+		});
+	}
+
+	playstate(state) {
+		this.signal.postMessage({
+			type: "playstate",
+			payload: state
+		});
+	}
+
+}
diff --git a/js/modules/Gun.mjs b/js/modules/Gun.mjs
deleted file mode 100644
index 4146ac6..0000000
--- a/js/modules/Gun.mjs
+++ /dev/null
@@ -1,24 +0,0 @@
-export class RasterScan {
-
-	constructor(pixels) {
-		this.pixels = pixels;
-		this.coils = new Worker("./js/modules/Raster.mjs");
-
-		this.coils.addEventListener("message",event => {
-			this.fire(event.data);
-		});
-	}
-
-	fire(data) {
-		this.pixels[data.pixel].style.setProperty("background",data.color);
-		this.pixels[data.pixel].style.setProperty("animation",`decay 10ms ${data.pixel} linear forwards`);
-	}
-
-	load(tape) {
-		this.coils.postMessage({
-			density: this.pixels.length,
-			tape: tape
-		});
-	}
-
-}
\ No newline at end of file
diff --git a/js/modules/Helper.mjs b/js/modules/Helper.mjs
new file mode 100644
index 0000000..a9b7382
--- /dev/null
+++ b/js/modules/Helper.mjs
@@ -0,0 +1,4 @@
+export async function fetchJSON(url) {
+	const response = await fetch(url);
+	return response.json();
+}
diff --git a/js/modules/Raster.mjs b/js/modules/Raster.mjs
index 52eada3..5f24594 100644
--- a/js/modules/Raster.mjs
+++ b/js/modules/Raster.mjs
@@ -1,17 +1,16 @@
-let field;
-let clock;
+let meta = {
+	fields: 0,
+	pixels: 0,
+	framerate: 100
+};
 
-let tape = {
-	header: (data) => {
-		clock = data.framerate;
-		this.format = format;
+let clock = null;
 
-		self.postMessage({
-			type: "resolutionUpdate",
-			data: resolution
-		});
-	},
-	stream: []
+let tape = null;
+let stream = (stream) => {
+	meta.fields = Math.floor(stream.length / meta.pixels);
+	tape = stream;
+	return true;
 }
 
 async function fetchJSON(url) {
@@ -19,11 +18,47 @@ async function fetchJSON(url) {
 	return response.json();
 }
 
-function loadTape(ref) {
-	fetchJSON(ref + "/header.json").then(data => tape.header(data));
-	fetchJSON(ref + "/data.json").then(data => tape.stream = data);
+function scan() {
+	let pixel = 0;
+
+	for(let head = 0; head < tape.length; head++) {
+		if(pixel == meta.pixels) {
+			pixel = 0;
+		}
+
+		self.postMessage({
+			index: pixel,
+			color: tape[head]
+		});
+
+		pixel++;
+	}
+}
+
+function playstate(state) {
+	if(state == "play") {
+		clock = setInterval(scan,meta.framerate);
+		return;
+	}
+	clock = null;
 }
 
 self.addEventListener("message",event => {
-	loadTape(event.data.tape);
-});
\ No newline at end of file
+	const payload = event.data.payload;
+
+	switch(event.data.type) {
+		case "headers":
+			meta.pixels = payload.resolution[0] * payload.resolution[1];
+			meta.framerate = payload.framerate;
+
+			const segmentURL = new Array("../../tapes",payload.manifest,payload.segments[0]).join("/");
+			fetchJSON(segmentURL).then(tape => stream(tape));
+			break;
+
+		case "playstate":
+			playstate(payload);
+			break;
+
+		default: console.warn("Unknown instruction: " + event.data.type); break;
+	}
+});
diff --git a/js/modules/Screen.mjs b/js/modules/Screen.mjs
index 1441978..abe34a8 100644
--- a/js/modules/Screen.mjs
+++ b/js/modules/Screen.mjs
@@ -4,6 +4,7 @@ export class FluorescentScreen {
 		this.screen = screen;
 		this.pixels = [];
 		
+		this.destroyPixels();
 		this.spawnPixels();
 	}
 
@@ -26,4 +27,10 @@ export class FluorescentScreen {
 		this.createMatrix();
 	}
 
-}
\ No newline at end of file
+	destroyPixels() {
+		while(this.screen.firstChild) {
+			this.screen.removeChild(this.screen.lastChild);
+		}
+	}
+
+}
diff --git a/tapes/sample/header.json b/tapes/sample/header.json
index 2dede99..fd27dde 100644
--- a/tapes/sample/header.json
+++ b/tapes/sample/header.json
@@ -1,5 +1,9 @@
 {
+	"manifest": "sample",
 	"format": "signed-hex",
-	"resolution": ["64","64"],
-	"framerate": 10
-}
\ No newline at end of file
+	"resolution": ["32","32"],
+	"framerate": 100,
+	"segments": [
+		"data.json"
+	]
+}