<html xml:lang="en" lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head>
<script>
- var canvas;
- var context;
- function drawplot(times, color) {
- var tmin = times[0][0];
- var tfact = 640/(times[times.length-1][0] - tmin);
+ var dbg;
+ var xmlhttp;
+ var canvas, ctx;
+ var ww, wh;
+ var hmax, hfact;
+ var tmin, tmax, tfact;
+ var xzero = 20, yzero = 20;
+ var cold_d = [], hot_d = [];
+
+ function px(x) {
+ return xzero + ((x - tmin) * tfact);
+ }
+ function py(y) {
+ return wh - yzero - (y * hfact);
+ }
+ function xaxis() {
+ ctx.beginPath();
+ ctx.moveTo(px(tmin), py(0));
+ ctx.lineTo(px(tmax), py(0));
+ ctx.strokeStyle = "black";
+ ctx.stroke();
+ }
+ function yaxis() {
+ ctx.beginPath();
+ ctx.moveTo(px(tmin), py(0));
+ ctx.lineTo(px(tmin), py(hmax));
+ ctx.strokeStyle = "black";
+ ctx.stroke();
+ }
+ /* @ updates global var `hmax` */
+ function differentiate(times) {
+ var res = [];
+ var dv, dt, v;
+
+ for (i = 0; i < times.length - 1; i++) {
+ dv = times[i+1][1] - times[i][1];
+ dt = times[i+1][0] - times[i][0];
+ if (dt != 0 && dv != 0) {
+ v = (dv / dt) * 360 ; /* Litres per hour */
+ if (hmax < v) hmax = v;
+ res.push([times[i][0], v]);
+ }
+ }
+ res.push([times[i][0], v]);
+
+ return res;
+ }
+ function drawplot(data, color) {
var i;
- var height = [];
- var hmax = 0;
- var hfact;
- for (i = 1; i < times.length; i++) {
- height[i] = 1 / (times[i][0] - times[i-1][0]);
- if (hmax < height[i]) hmax = height[i];
+ ctx.beginPath();
+ ctx.moveTo(px(data[0][0]), py(data[0][1]));
+ for (i = 1; i < data.length; i++) {
+ ctx.lineTo(px(data[i][0]), py(data[i - 1][1]));
+ ctx.lineTo(px(data[i][0]), py(data[i][1]));
}
- height[i+1] = height[i];
- hfact = 480 / hmax;
- context.beginPath();
- context.moveTo(0, 480 - height[1]*hfact);
- for (i = 1; i < times.length; i++) {
- context.lineTo((times[i][0] - tmin)*tfact,480 - height[i]*hfact);
- context.lineTo((times[i][0] - tmin)*tfact,480 - height[i+1]*hfact);
+ ctx.strokeStyle = color;
+ ctx.stroke();
+ }
+ function showloading() {
+ ctx.fillStyle = "green";
+ ctx.font = "bold 16px Courier";
+ ctx.fillText("loading", (ww / 2) - 40 , (wh / 2) + 8);
+ }
+ function clearplot() {
+ ctx.clearRect(0, 0, ww, wh);
+ }
+ function redraw() {
+ if (cold_d.length && hot_d.length) {
+ clearplot();
+ drawplot(cold_d, "blue");
+ drawplot(hot_d, "red");
+ xaxis();
+ yaxis();
+ } else {
+ showloading();
}
- context.strokeStyle = color;
- context.stroke();
}
+
function gotdata(data) {
+ document.getElementById("cold").innerHTML =
+ (data.current.cold / 100).toFixed(2);
+ document.getElementById("hot").innerHTML =
+ (data.current.hot / 100).toFixed(2);
+ tmin = data.range.lo;
+ tmax = data.range.hi;
+ tfact = (ww - xzero) / (tmax - tmin);
+ /* differetiate() updates hmax */
+ hmax = 0;
+ cold_d = differentiate(data.cold);
+ hot_d = differentiate(data.hot);
+ hfact = (wh - yzero) / hmax;
+ //dbg.innerHTML = "hmax=" + hmax + " hfact=" + hfact + "<br>"
+ // + cold_d + "<br>" + hot_d;
+ redraw();
+ }
+
+ function sendquery(lo, hi) {
+ var url = "query.cgi";
+
+ if (lo && hi) url += "?lo=" + lo + "&" + hi;
+ else url = "query.cgi?lo=2015-12-19+00:00:00&hi=2015-12-20+00:00:00"; //FIX
+ xmlhttp.onreadystatechange = function() {
+ if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
+ // dbg.innerHTML = xmlhttp.responseText;
+ var myData = JSON.parse(xmlhttp.responseText);
+ gotdata(myData);
+ }
+ }
+ xmlhttp.open("GET", url, true);
+ xmlhttp.send();
+ }
+
+ function resize() {
+ ww = window.innerWidth - 4;
+ if (ww > window.innerHeight) ww = window.innerHeight;
+ wh = ww / 2;
+ canvas.width = ww;
+ canvas.height = wh;
+ canvas.style.width = ww + "px";
+ canvas.style.height = wh + "px";
+ redraw();
+ }
+
+ function initialize() {
+ dbg = document.getElementById("debug");
canvas = document.getElementById("plot");
- context = canvas.getContext("2d");
- drawplot(data.cold, "blue");
- drawplot(data.hot, "red");
+ ctx = canvas.getContext("2d");
+ xmlhttp = new XMLHttpRequest();
+ resize();
+ sendquery();
+ }
+
+ /* Set up */
+ if(window.attachEvent) {
+ window.attachEvent('onload', initialize);
+ window.attachEvent('onresize', resize);
+ } else {
+ window.onload = initialize;
+ window.onresize = resize;
}
</script>
+<style>
+h1 {
+ text-align: center;
+}
+br {
+ clear: both;
+}
+div#currentvals {
+ width: 18em;
+ margin-left: auto;
+ margin-right: auto;
+ margin-bottom: 10px;
+ text-align: center;
+ font-size: 150%;
+}
+div.current {
+ position: relative;
+ padding: 0.2em;
+ border: solid 1px black;
+ margin: 0.2em;
+}
+div#cold {
+ float: left;
+ background-color: #d0e0ff;
+}
+div#hot {
+ float: right;
+ background-color: #ffd0e0;
+}
+canvas#plot {
+ padding: 0px;
+ margin: auto;
+ display: block;
+ width: 640px;
+ height: 320px;
+ border: solid 1px black;
+}
+body {
+ margin: 0px;
+}
+</style>
+<title>Water Meters</title>
</head><body>
-<canvas id="plot" width="640" height = "480"
- style="border:solid 1px #000000;"></canvas>
-<hr/>
+<h1>Water Meters</h1>
+<div id="currentvals">
+ Current Values
+ <div class="current" id="cold">cold</div>
+ <div class="current" id="hot">hot</div>
+</div>
+<br />
+<canvas id="plot" width="640" height = "320"></canvas>
+<br />
<div id=debug>
</div>
-<script>
- var xmlhttp = new XMLHttpRequest();
- var url = "query.cgi";
-
- xmlhttp.onreadystatechange = function() {
- if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
- document.getElementById("debug").innerHTML = xmlhttp.responseText;
- var myData = JSON.parse(xmlhttp.responseText);
- gotdata(myData);
- }
- }
- xmlhttp.open("GET", url, true);
- xmlhttp.send();
-</script>
</body>
projects / pulsecounter.git / blobdiff