ImageUtils.js 992 字节
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
/**
 * @author mrdoob / http://mrdoob.com/
 * @author alteredq / http://alteredqualia.com/
 * @author szimek / https://github.com/szimek/
 */

var ImageUtils = {

	getDataURL: function ( image ) {

		var canvas;

		if ( image instanceof HTMLCanvasElement ) {

			canvas = image;

		} else {

			if ( typeof OffscreenCanvas !== 'undefined' ) {

				canvas = new OffscreenCanvas( image.width, image.height );

			} else {

				canvas = document.createElementNS( 'http://www.w3.org/1999/xhtml', 'canvas' );
				canvas.width = image.width;
				canvas.height = image.height;

			}

			var context = canvas.getContext( '2d' );

			if ( image instanceof ImageData ) {

				context.putImageData( image, 0, 0 );

			} else {

				context.drawImage( image, 0, 0, image.width, image.height );

			}

		}

		if ( canvas.width > 2048 || canvas.height > 2048 ) {

			return canvas.toDataURL( 'image/jpeg', 0.6 );

		} else {

			return canvas.toDataURL( 'image/png' );

		}

	}

};

export { ImageUtils };