Express server set up.

server/pub/patterns/HorizontalBar.js

@@ -0,0 +1,21 @@
+"use strict";
+
+function bindHorizontalBar(canvasElement, visualizerCore) {
+    let _width = canvasElement.width;
+    let _height = canvasElement.height;
+    let _canvasCtx = canvasElement.getContext("2d");
+    let _visualizerCore = visualizerCore;
+    let update = function (delta, bins) {
+        _canvasCtx.clearRect(0, 0, _width, _height); // clear canvas.
+        let barWidth = Math.floor(_width / bins.length) - 1; // -1 for 1 pixel gap between bars.
+        let barIndex = 0;
+        bins.forEach(bin => {
+            let normalBin = bin / 255.0;
+            _canvasCtx.fillStyle = "rgb(" + 0 + "," + bin + "," + bin + ")";
+            let barHeight = _height * normalBin;
+            _canvasCtx.fillRect(barIndex * barWidth, _height - barHeight, barWidth, barHeight);
+            barIndex += 1;
+        });
+    };
+    _visualizerCore.addUpdateListener(update);
+}