mirror of
https://github.com/ConnectedHumber/Air-Quality-Web
synced 2024-11-17 05:43:01 +00:00
129 lines
3.6 KiB
JavaScript
129 lines
3.6 KiB
JavaScript
window.spec = {
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"0": "#9CFF9C", "5.5": "#9CFF9C", // Low 1
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"17.5": "#31FF00", // Low 2
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"29.5": "#31CF00", // Low 3
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"38.5": "#FFFF00", // Moderate 1
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"44.5": "#FFCF00", // Moderate 2
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"50.5": "#FF9A00", // Moderate 3
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"56": "#FF6464", // High 1
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"61.5": "#FF0000", // High 2
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"67.5": "#990000", // High 3
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"72.5": "#CE30FF", "75": "#CE30FF", // Very high
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}
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window.max = 75;
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window.addEventListener("load", (_event) => {
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let canvas = document.getElementById("main");
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let guage = new Guage(canvas, window.spec, window.max);
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guage.render();
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});
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window.pixel_ratio = (function () {
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let ctx = document.createElement("canvas").getContext("2d"),
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dpr = window.devicePixelRatio || 1,
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bsr = ctx.webkitBackingStorePixelRatio ||
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ctx.mozBackingStorePixelRatio ||
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ctx.msBackingStorePixelRatio ||
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ctx.oBackingStorePixelRatio ||
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ctx.backingStorePixelRatio || 1;
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return dpr / bsr;
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})();
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function set_hidpi_canvas(canvas, width, height) {
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width = width || canvas.width;
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height = height || canvas.height;
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canvas.width = width * pixel_ratio;
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canvas.height = height * pixel_ratio;
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canvas.style.width = width + "px";
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canvas.style.height = height + "px";
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// canvas.getContext("2d").setTransform(pixel_ratio, 0, 0, pixel_ratio, 0, 0);
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return canvas;
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}
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class Guage {
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constructor(in_canvas, in_spec, in_max) {
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this.canvas = in_canvas;
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this.spec = in_spec;
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this.max = in_max;
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set_hidpi_canvas(this.canvas);
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// TODO: Use Helpers/Canvas.mjs here
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this.pixelRatio = (function () {
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var ctx = document.createElement("canvas").getContext("2d"),
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dpr = window.devicePixelRatio || 1,
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bsr = ctx.webkitBackingStorePixelRatio ||
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ctx.mozBackingStorePixelRatio ||
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ctx.msBackingStorePixelRatio ||
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ctx.oBackingStorePixelRatio ||
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ctx.backingStorePixelRatio || 1;
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return dpr / bsr;
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})();
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this.context = this.canvas.getContext("2d");
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}
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render() {
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let guage_size = {
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x: this.canvas.width * 0.1,
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y: this.canvas.height * 0.05,
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width: this.canvas.width * 0.3,
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height: this.canvas.height * 0.9
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};
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// ---------------------------------------------
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// Draw the guage
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this.context.save();
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let gradient_spec = RenderGradient(spec, max);
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console.log(gradient_spec);
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let gradient = this.context.createLinearGradient(
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0, guage_size.y,
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0, guage_size.y + guage_size.height
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);
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for (let point in gradient_spec)
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gradient.addColorStop(parseFloat(point), gradient_spec[point]);
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this.context.fillStyle = gradient;
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this.context.fillRect(guage_size.x, guage_size.y, guage_size.width, guage_size.height);
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this.context.restore();
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// ---------------------------------------------
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// Draw the numbers
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this.context.save();
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this.context.font = "12px Ubuntu, sans-serif";
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this.context.textBaseline = "middle";
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this.context.strokeStyle = "rgba(0, 0, 0, 0.5)";
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this.context.lineWidth = 1.5 * window.pixel_ratio;
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for (let point in spec) {
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let value = parseFloat(point) / max;
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let draw_x = guage_size.x + guage_size.width + 3;
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let draw_y = guage_size.y + (value * guage_size.height);
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// this.context.fillStyle = "black";
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console.log(`Writing '${point}' to (${draw_x}, ${draw_y})`);
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this.context.fillText(point, draw_x, draw_y);
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this.context.beginPath();
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this.context.moveTo(guage_size.x, draw_y);
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this.context.lineTo(draw_x, draw_y);
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this.context.stroke();
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}
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this.context.restore();
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}
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}
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function RenderGradient(stops, max) {
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let result = {};
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for (let value in stops)
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result[value / max] = stops[value];
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return result;
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}
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