/**
* Copyright (c) 2009 Chris Leonello
* jqPlot is currently available for use in all personal or commercial projects
* under both the MIT and GPL version 2.0 licenses. This means that you can
* choose the license that best suits your project and use it accordingly.
*
* The author would appreciate an email letting him know of any substantial
* use of jqPlot. You can reach the author at: chris dot leonello at gmail
* dot com or see http://www.jqplot.com/info.php . This is, of course,
* not required.
*
* If you are feeling kind and generous, consider supporting the project by
* making a donation at: http://www.jqplot.com/donate.php .
*
* Thanks for using jqPlot!
*
*/
(function($) {
/**
* Class: $.jqplot.CanvasAxisLabelRenderer
* Renderer to draw axis labels with a canvas element to support advanced
* featrues such as rotated text. This renderer uses a separate rendering engine
* to draw the text on the canvas. Two modes of rendering the text are available.
* If the browser has native font support for canvas fonts (currently Mozila 3.5
* and Safari 4), you can enable text rendering with the canvas fillText method.
* You do so by setting the "enableFontSupport" option to true.
*
* Browsers lacking native font support will have the text drawn on the canvas
* using the Hershey font metrics. Even if the "enableFontSupport" option is true
* non-supporting browsers will still render with the Hershey font.
*
*/
$.jqplot.CanvasAxisLabelRenderer = function(options) {
// Group: Properties
// prop: angle
// angle of text, measured clockwise from x axis.
this.angle = 0;
// name of the axis associated with this tick
this.axis;
// prop: show
// wether or not to show the tick (mark and label).
this.show = true;
// prop: showLabel
// wether or not to show the label.
this.showLabel = true;
// prop: label
// label for the axis.
this.label = '';
// prop: fontFamily
// CSS spec for the font-family css attribute.
// Applies only to browsers supporting native font rendering in the
// canvas tag. Currently Mozilla 3.5 and Safari 4.
this.fontFamily = '"Trebuchet MS", Arial, Helvetica, sans-serif';
// prop: fontSize
// CSS spec for font size.
this.fontSize = '11pt';
// prop: fontWeight
// CSS spec for fontWeight: normal, bold, bolder, lighter or a number 100 - 900
this.fontWeight = 'normal';
// prop: fontStretch
// Multiplier to condense or expand font width.
// Applies only to browsers which don't support canvas native font rendering.
this.fontStretch = 1.0;
// prop: textColor
// css spec for the color attribute.
this.textColor = '#666666';
// prop: enableFontSupport
// true to turn on native canvas font support in Mozilla 3.5+ and Safari 4+.
// If true, label will be drawn with canvas tag native support for fonts.
// If false, label will be drawn with Hershey font metrics.
this.enableFontSupport = false;
// prop: pt2px
// Point to pixel scaling factor, used for computing height of bounding box
// around a label. The labels text renderer has a default setting of 1.4, which
// should be suitable for most fonts. Leave as null to use default. If tops of
// letters appear clipped, increase this. If bounding box seems too big, decrease.
// This is an issue only with the native font renderering capabilities of Mozilla
// 3.5 and Safari 4 since they do not provide a method to determine the font height.
this.pt2px = null;
this._elem;
this._ctx;
this._plotWidth;
this._plotHeight;
this._plotDimensions = {height:null, width:null};
$.extend(true, this, options);
if (options.angle == null && this.axis != 'xaxis' && this.axis != 'x2axis') {
this.angle = -90;
}
var ropts = {fontSize:this.fontSize, fontWeight:this.fontWeight, fontStretch:this.fontStretch, fillStyle:this.textColor, angle:this.getAngleRad(), fontFamily:this.fontFamily};
if (this.pt2px) {
ropts.pt2px = this.pt2px;
}
if (this.enableFontSupport) {
if ($.browser.safari) {
var p = $.browser.version.split('.');
for (var i=0; i<p.length; i++) { p[i] = Number(p[i]); }
if (p[0] > 528 || (p[0] == 528 && p[1] >= 16)) {
this._textRenderer = new $.jqplot.CanvasFontRenderer(ropts);
}
}
else if ($.browser.mozilla) {
var p = $.browser.version.split(".");
if (p[0] > 1 || (p[0] == 1 && p[1] >= 9 && p[2] > 0) ) {
this._textRenderer = new $.jqplot.CanvasFontRenderer(ropts);
}
else {
this._textRenderer = new $.jqplot.CanvasTextRenderer(ropts);
}
}
// TODO: test and enable this
// else if ($.browser.msie) {
// this._textRenderer = new $.jqplot.CanvasFontRenderer(ropts);
// }
else {
this._textRenderer = new $.jqplot.CanvasTextRenderer(ropts);
}
}
else {
this._textRenderer = new $.jqplot.CanvasTextRenderer(ropts);
}
};
$.jqplot.CanvasAxisLabelRenderer.prototype.init = function(options) {
$.extend(true, this, options);
this._textRenderer.init({fontSize:this.fontSize, fontWeight:this.fontWeight, fontStretch:this.fontStretch, fillStyle:this.textColor, angle:this.getAngleRad(), fontFamily:this.fontFamily});
};
// return width along the x axis
// will check first to see if an element exists.
// if not, will return the computed text box width.
$.jqplot.CanvasAxisLabelRenderer.prototype.getWidth = function(ctx) {
if (this._elem) {
return this._elem.outerWidth(true);
}
else {
var tr = this._textRenderer;
var l = tr.getWidth(ctx);
var h = tr.getHeight(ctx);
var w = Math.abs(Math.sin(tr.angle)*h) + Math.abs(Math.cos(tr.angle)*l);
return w;
}
};
// return height along the y axis.
$.jqplot.CanvasAxisLabelRenderer.prototype.getHeight = function(ctx) {
if (this._elem) {
return this._elem.outerHeight(true);
}
else {
var tr = this._textRenderer;
var l = tr.getWidth(ctx);
var h = tr.getHeight(ctx);
var w = Math.abs(Math.cos(tr.angle)*h) + Math.abs(Math.sin(tr.angle)*l);
return w;
}
};
$.jqplot.CanvasAxisLabelRenderer.prototype.getAngleRad = function() {
var a = this.angle * Math.PI/180;
return a;
};
$.jqplot.CanvasAxisLabelRenderer.prototype.draw = function(ctx) {
// create a canvas here, but can't draw on it untill it is appended
// to dom for IE compatability.
var domelem = document.createElement('canvas');
this._textRenderer.setText(this.label, ctx);
var w = this.getWidth(ctx);
var h = this.getHeight(ctx);
domelem.width = w;
domelem.height = h;
domelem.style.width = w;
domelem.style.height = h;
// domelem.style.textAlign = 'center';
domelem.style.position = 'absolute';
this._domelem = domelem;
this._elem = $(domelem);
this._elem.addClass('jqplot-'+this.axis+'-label');
return this._elem;
};
$.jqplot.CanvasAxisLabelRenderer.prototype.pack = function() {
if ($.browser.msie) {
window.G_vmlCanvasManager.init_(document);
this._domelem = window.G_vmlCanvasManager.initElement(this._domelem);
}
var ctx = this._elem.get(0).getContext("2d");
this._textRenderer.draw(ctx, this.label);
};
})(jQuery);