/**
* @author Richard Davey <rich@photonstorm.com>
* @copyright 2013 Photon Storm Ltd.
* @license {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
*/
/**
* The Canvas class handles everything related to the <canvas> tag as a DOM Element, like styles, offset, aspect ratio
*
* @class Phaser.Canvas
* @static
*/
Phaser.Canvas = {
/**
* Creates the <canvas> tag
*
* @method Phaser.Canvas.create
* @param {number} width - The desired width.
* @param {number} height - The desired height.
* @return {HTMLCanvasElement} The newly created <canvas> tag.
*/
create: function (width, height) {
width = width || 256;
height = height || 256;
var canvas = document.createElement('canvas');
canvas.width = width;
canvas.height = height;
canvas.style.display = 'block';
return canvas;
},
/**
* Get the DOM offset values of any given element
* @method Phaser.Canvas.getOffset
* @param {HTMLElement} element - The targeted element that we want to retrieve the offset.
* @param {Phaser.Point} [point] - The point we want to take the x/y values of the offset.
* @return {Phaser.Point} - A point objet with the offsetX and Y as its properties.
*/
getOffset: function (element, point) {
point = point || new Phaser.Point();
var box = element.getBoundingClientRect();
var clientTop = element.clientTop || document.body.clientTop || 0;
var clientLeft = element.clientLeft || document.body.clientLeft || 0;
var scrollTop = window.pageYOffset || element.scrollTop || document.body.scrollTop;
var scrollLeft = window.pageXOffset || element.scrollLeft || document.body.scrollLeft;
point.x = box.left + scrollLeft - clientLeft;
point.y = box.top + scrollTop - clientTop;
return point;
},
/**
* Returns the aspect ratio of the given canvas.
*
* @method Phaser.Canvas.getAspectRatio
* @param {HTMLCanvasElement} canvas - The canvas to get the aspect ratio from.
* @return {number} The ratio between canvas' width and height.
*/
getAspectRatio: function (canvas) {
return canvas.width / canvas.height;
},
/**
* Sets the background color behind the canvas. This changes the canvas style property.
*
* @method Phaser.Canvas.setBackgroundColor
* @param {HTMLCanvasElement} canvas - The canvas to set the background color on.
* @param {string} [color] - The color to set. Can be in the format 'rgb(r,g,b)', or '#RRGGBB' or any valid CSS color.
* @return {HTMLCanvasElement} Returns the source canvas.
*/
setBackgroundColor: function (canvas, color) {
color = color || 'rgb(0,0,0)';
canvas.style.backgroundColor = color;
return canvas;
},
/**
* Sets the touch-action property on the canvas style. Can be used to disable default browser touch actions.
*
* @method Phaser.Canvas.setTouchAction
* @param {HTMLCanvasElement} canvas - The canvas to set the touch action on.
* @param {String} [value] - The touch action to set. Defaults to 'none'.
* @return {HTMLCanvasElement} The source canvas.
*/
setTouchAction: function (canvas, value) {
value = value || 'none';
canvas.style.msTouchAction = value;
canvas.style['ms-touch-action'] = value;
canvas.style['touch-action'] = value;
return canvas;
},
/**
* Sets the user-select property on the canvas style. Can be used to disable default browser selection actions.
*
* @method Phaser.Canvas.setUserSelect
* @param {HTMLCanvasElement} canvas - The canvas to set the touch action on.
* @param {String} [value] - The touch action to set. Defaults to 'none'.
* @return {HTMLCanvasElement} The source canvas.
*/
setUserSelect: function (canvas, value) {
value = value || 'none';
canvas.style['-webkit-touch-callout'] = value;
canvas.style['-webkit-user-select'] = value;
canvas.style['-khtml-user-select'] = value;
canvas.style['-moz-user-select'] = value;
canvas.style['-ms-user-select'] = value;
canvas.style['user-select'] = value;
canvas.style['-webkit-tap-highlight-color'] = 'rgba(0, 0, 0, 0)';
return canvas;
},
/**
* Adds the given canvas element to the DOM. The canvas will be added as a child of the given parent.
* If no parent is given it will be added as a child of the document.body.
*
* @method Phaser.Canvas.addToDOM
* @param {HTMLCanvasElement} canvas - The canvas to set the touch action on.
* @param {string|HTMLElement} parent - The DOM element to add the canvas to. Defaults to ''.
* @param {boolean} overflowHidden - If set to true it will add the overflow='hidden' style to the parent DOM element.
* @return {HTMLCanvasElement} Returns the source canvas.
*/
addToDOM: function (canvas, parent, overflowHidden) {
var target;
if (typeof overflowHidden === 'undefined') { overflowHidden = true; }
if (parent)
{
// hopefully an element ID
if (typeof parent === 'string')
{
target = document.getElementById(parent);
}
// quick test for a HTMLelement
else if (typeof parent === 'object' && parent.nodeType === 1)
{
target = parent;
}
if (overflowHidden)
{
target.style.overflow = 'hidden';
}
}
// fallback, covers an invalid ID and a none HTMLelement object
if(!target)
{
target = document.body;
}
target.appendChild(canvas);
return canvas;
},
/**
* Sets the transform of the given canvas to the matrix values provided.
*
* @method Phaser.Canvas.setTransform
* @param {CanvasRenderingContext2D} context - The context to set the transform on.
* @param {number} translateX - The value to translate horizontally by.
* @param {number} translateY - The value to translate vertically by.
* @param {number} scaleX - The value to scale horizontally by.
* @param {number} scaleY - The value to scale vertically by.
* @param {number} skewX - The value to skew horizontaly by.
* @param {number} skewY - The value to skew vertically by.
* @return {CanvasRenderingContext2D} Returns the source context.
*/
setTransform: function (context, translateX, translateY, scaleX, scaleY, skewX, skewY) {
context.setTransform(scaleX, skewX, skewY, scaleY, translateX, translateY);
return context;
},
/**
* Sets the Image Smoothing property on the given context. Set to false to disable image smoothing.
* By default browsers have image smoothing enabled, which isn't always what you visually want, especially
* when using pixel art in a game. Note that this sets the property on the context itself, so that any image
* drawn to the context will be affected. This sets the property across all current browsers but support is
* patchy on earlier browsers, especially on mobile.
*
* @method Phaser.Canvas.setSmoothingEnabled
* @param {CanvasRenderingContext2D} context - The context to enable or disable the image smoothing on.
* @param {boolean} value - If set to true it will enable image smoothing, false will disable it.
* @return {CanvasRenderingContext2D} Returns the source context.
*/
setSmoothingEnabled: function (context, value) {
context['imageSmoothingEnabled'] = value;
context['mozImageSmoothingEnabled'] = value;
context['oImageSmoothingEnabled'] = value;
context['webkitImageSmoothingEnabled'] = value;
context['msImageSmoothingEnabled'] = value;
return context;
},
/**
* Sets the CSS image-rendering property on the given canvas to be 'crisp' (aka 'optimize contrast on webkit').
* Note that if this doesn't given the desired result then see the setSmoothingEnabled.
*
* @method Phaser.Canvas.setImageRenderingCrisp
* @param {HTMLCanvasElement} canvas - The canvas to set image-rendering crisp on.
* @return {HTMLCanvasElement} Returns the source canvas.
*/
setImageRenderingCrisp: function (canvas) {
canvas.style['image-rendering'] = 'crisp-edges';
canvas.style['image-rendering'] = '-moz-crisp-edges';
canvas.style['image-rendering'] = '-webkit-optimize-contrast';
canvas.style.msInterpolationMode = 'nearest-neighbor';
return canvas;
},
/**
* Sets the CSS image-rendering property on the given canvas to be 'bicubic' (aka 'auto').
* Note that if this doesn't given the desired result then see the CanvasUtils.setSmoothingEnabled method.
*
* @method Phaser.Canvas.setImageRenderingBicubic
* @param {HTMLCanvasElement} canvas The canvas to set image-rendering bicubic on.
* @return {HTMLCanvasElement} Returns the source canvas.
*/
setImageRenderingBicubic: function (canvas) {
canvas.style['image-rendering'] = 'auto';
canvas.style.msInterpolationMode = 'bicubic';
return canvas;
}
};