1 /* Flot plugin that adds some extra symbols for plotting points.
3 Copyright (c) 2007-2013 IOLA and Ole Laursen.
4 Licensed under the MIT license.
6 The symbols are accessed as strings through the standard symbol options:
10 symbol: "square" // or "diamond", "triangle", "cross"
17 function processRawData(plot, series, datapoints) {
18 // we normalize the area of each symbol so it is approximately the
19 // same as a circle of the given radius
22 square: function (ctx, x, y, radius, shadow) {
23 // pi * r^2 = (2s)^2 => s = r * sqrt(pi)/2
24 var size = radius * Math.sqrt(Math.PI) / 2;
25 ctx.rect(x - size, y - size, size + size, size + size);
27 diamond: function (ctx, x, y, radius, shadow) {
28 // pi * r^2 = 2s^2 => s = r * sqrt(pi/2)
29 var size = radius * Math.sqrt(Math.PI / 2);
30 ctx.moveTo(x - size, y);
31 ctx.lineTo(x, y - size);
32 ctx.lineTo(x + size, y);
33 ctx.lineTo(x, y + size);
34 ctx.lineTo(x - size, y);
36 triangle: function (ctx, x, y, radius, shadow) {
37 // pi * r^2 = 1/2 * s^2 * sin (pi / 3) => s = r * sqrt(2 * pi / sin(pi / 3))
38 var size = radius * Math.sqrt(2 * Math.PI / Math.sin(Math.PI / 3));
39 var height = size * Math.sin(Math.PI / 3);
40 ctx.moveTo(x - size/2, y + height/2);
41 ctx.lineTo(x + size/2, y + height/2);
43 ctx.lineTo(x, y - height/2);
44 ctx.lineTo(x - size/2, y + height/2);
47 cross: function (ctx, x, y, radius, shadow) {
48 // pi * r^2 = (2s)^2 => s = r * sqrt(pi)/2
49 var size = radius * Math.sqrt(Math.PI) / 2;
50 ctx.moveTo(x - size, y - size);
51 ctx.lineTo(x + size, y + size);
52 ctx.moveTo(x - size, y + size);
53 ctx.lineTo(x + size, y - size);
57 var s = series.points.symbol;
59 series.points.symbol = handlers[s];
63 plot.hooks.processDatapoints.push(processRawData);