///
/**
* @author Richard Davey
* @copyright 2013 Photon Storm Ltd.
* @license https://github.com/photonstorm/phaser/blob/master/license.txt MIT License
* @module Phaser
*/
module Phaser {
/**
* A collection of methods useful for manipulating canvas objects.
*
* @class CanvasUtils
*/
export class CanvasUtils {
/**
* Returns the aspect ratio of the given canvas.
*
* @method getAspectRatio
* @param {HTMLCanvasElement} canvas The canvas to get the aspect ratio from.
* @return {Number} Returns true on success
*/
public static getAspectRatio(canvas: HTMLCanvasElement): number {
return canvas.width / canvas.height;
}
/**
* Sets the background color behind the canvas. This changes the canvas style property.
*
* @method 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.
*/
public static setBackgroundColor(canvas: HTMLCanvasElement, color: string = 'rgb(0,0,0)'): HTMLCanvasElement {
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 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} Returns the source canvas.
*/
public static setTouchAction(canvas: HTMLCanvasElement, value: string= 'none'): HTMLCanvasElement {
canvas.style.msTouchAction = value;
canvas.style['ms-touch-action'] = value;
canvas.style['touch-action'] = value;
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 addToDOM
* @param {HTMLCanvasElement} canvas The canvas to set the touch action on.
* @param {String} parent The DOM element to add the canvas to. Defaults to ''.
* @param {bool} overflowHidden If set to true it will add the overflow='hidden' style to the parent DOM element.
* @return {HTMLCanvasElement} Returns the source canvas.
*/
public static addToDOM(canvas: HTMLCanvasElement, parent: string = '', overflowHidden: bool = true): HTMLCanvasElement {
if ((parent !== '' || parent !== null) && document.getElementById(parent))
{
document.getElementById(parent).appendChild(canvas);
if (overflowHidden)
{
document.getElementById(parent).style.overflow = 'hidden';
}
}
else
{
document.body.appendChild(canvas);
}
return canvas;
}
/**
* Sets the transform of the given canvas to the matrix values provided.
*
* @method 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.
*/
public static setTransform(context: CanvasRenderingContext2D, translateX: number, translateY: number, scaleX: number, scaleY: number, skewX: number, skewY: number): CanvasRenderingContext2D {
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 setSmoothingEnabled
* @param {CanvasRenderingContext2D} context The context to enable or disable the image smoothing on.
* @param {bool} overflowHidden If set to true it will enable image smoothing, false will disable it.
* @return {CanvasRenderingContext2D} Returns the source context.
*/
public static setSmoothingEnabled(context: CanvasRenderingContext2D, value: bool): CanvasRenderingContext2D {
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 CanvasUtils.setSmoothingEnabled method.
*
* @method setImageRenderingCrisp
* @param {HTMLCanvasElement} canvas The canvas to set image-rendering crisp on.
* @return {HTMLCanvasElement} Returns the source canvas.
*/
public static setImageRenderingCrisp(canvas: HTMLCanvasElement): HTMLCanvasElement {
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 setImageRenderingBicubic
* @param {HTMLCanvasElement} canvas The canvas to set image-rendering bicubic on.
* @return {HTMLCanvasElement} Returns the source canvas.
*/
public static setImageRenderingBicubic(canvas: HTMLCanvasElement): HTMLCanvasElement {
canvas.style['image-rendering'] = 'auto';
canvas.style.msInterpolationMode = 'bicubic';
return canvas;
}
}
}