Dedicated project page for chip8 sim.

web/static/apps/sim/init.js

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+var odinMemoryInterface = new odin.WasmMemoryInterface();
+odinMemoryInterface.setIntSize(4);
+var odinImports = odin.setupDefaultImports(odinMemoryInterface);
+
+// The Module is used as configuration for emscripten.
+var Module = {
+	// This is called by emscripten when it starts up.
+	instantiateWasm: (imports, successCallback) => {
+		const newImports = {
+			...odinImports,
+			...imports
+		}
+
+		return WebAssembly.instantiateStreaming(fetch("/web/static/apps/sim/index.wasm"), newImports).then(function(output) {
+			var e = output.instance.exports;
+			odinMemoryInterface.setExports(e);
+			odinMemoryInterface.setMemory(e.memory);
+			return successCallback(output.instance);
+		});
+	},
+	// This happens a bit after `instantiateWasm`, when everything is
+	// done setting up. At that point we can run code.
+	onRuntimeInitialized: () => {
+		var e = wasmExports;
+
+		// Calls any procedure marked with @init
+		e._start();
+
+		// See source/main_web/main_web.odin for main_start,
+		// main_update and main_end.
+		e.main_start();
+
+		function send_resize() {
+			var canvas = document.getElementById('canvas');
+			e.web_window_size_changed(canvas.width, canvas.height);
+		}
+
+		window.addEventListener('resize', function(event) {
+			send_resize();
+		}, true);
+
+		// This can probably be done better: Ideally we'd feed the
+		// initial size to `main_start`. But there seems to be a
+		// race condition. `canvas` doesn't have it's correct size yet.
+		send_resize();
+
+		// Runs the "main loop".
+		function do_main_update() {
+			if (!e.main_update()) {
+				e.main_end();
+
+				// Calls procedures marked with @fini
+				e._end();
+				return;
+			}
+			window.requestAnimationFrame(do_main_update);
+		}
+
+		window.requestAnimationFrame(do_main_update);
+	},
+	print: (function() {
+		var element = document.getElementById("output");
+		if (element) element.value = ''; // clear browser cache
+		return function(text) {
+			if (arguments.length > 1) text = Array.prototype.slice.call(arguments).join(' ');
+			console.log(text);
+			if (element) {
+			  element.value += text + "\n";
+			  element.scrollTop = element.scrollHeight; // focus on bottom
+			}
+		};
+	})(),
+	canvas: (function() {
+		return document.getElementById("canvas");
+	})()
+};