/* Flot plugin that adds some extra symbols for plotting points.



Copyright (c) 2007-2014 IOLA and Ole Laursen.

Licensed under the MIT license.



The symbols are accessed as strings through the standard symbol options:



	series: {

		points: {

			symbol: "square" // or "diamond", "triangle", "cross"

		}

	}



*/



(function ($) {

    function processRawData(plot, series, datapoints) {

        // we normalize the area of each symbol so it is approximately the

        // same as a circle of the given radius



        var handlers = {

            square: function (ctx, x, y, radius, shadow) {

                // pi * r^2 = (2s)^2  =>  s = r * sqrt(pi)/2

                var size = radius * Math.sqrt(Math.PI) / 2;

                ctx.rect(x - size, y - size, size + size, size + size);

            },

            diamond: function (ctx, x, y, radius, shadow) {

                // pi * r^2 = 2s^2  =>  s = r * sqrt(pi/2)

                var size = radius * Math.sqrt(Math.PI / 2);

                ctx.moveTo(x - size, y);

                ctx.lineTo(x, y - size);

                ctx.lineTo(x + size, y);

                ctx.lineTo(x, y + size);

                ctx.lineTo(x - size, y);

            },

            triangle: function (ctx, x, y, radius, shadow) {

                // pi * r^2 = 1/2 * s^2 * sin (pi / 3)  =>  s = r * sqrt(2 * pi / sin(pi / 3))

                var size = radius * Math.sqrt(2 * Math.PI / Math.sin(Math.PI / 3));

                var height = size * Math.sin(Math.PI / 3);

                ctx.moveTo(x - size/2, y + height/2);

                ctx.lineTo(x + size/2, y + height/2);

                if (!shadow) {

                    ctx.lineTo(x, y - height/2);

                    ctx.lineTo(x - size/2, y + height/2);

                }

            },

            cross: function (ctx, x, y, radius, shadow) {

                // pi * r^2 = (2s)^2  =>  s = r * sqrt(pi)/2

                var size = radius * Math.sqrt(Math.PI) / 2;

                ctx.moveTo(x - size, y - size);

                ctx.lineTo(x + size, y + size);

                ctx.moveTo(x - size, y + size);

                ctx.lineTo(x + size, y - size);

            }

        };



        var s = series.points.symbol;

        if (handlers[s])

            series.points.symbol = handlers[s];

    }

    

    function init(plot) {

        plot.hooks.processDatapoints.push(processRawData);

    }

    

    $.plot.plugins.push({

        init: init,

        name: 'symbols',

        version: '1.0'

    });

})(jQuery);

