Source/WebInspectorUI/UserInterface/Base/ImageUtilities.js

/*
 * Copyright (C) 2013, 2015 Apple Inc. All rights reserved.
 * Copyright (C) 2017 Devin Rousso <webkit@devinrousso.com>. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

WI.ImageUtilities = class ImageUtilities {
    static useSVGSymbol(url, className, title)
    {
        const svgNamespace = "http://www.w3.org/2000/svg";
        const xlinkNamespace = "http://www.w3.org/1999/xlink";

        let svgElement = document.createElementNS(svgNamespace, "svg");
        svgElement.style.width = "100%";
        svgElement.style.height = "100%";

        // URL must contain a fragment reference to a graphical element, like a symbol. If none is given
        // append #root which all of our SVGs have on the top level <svg> element.
        if (!url.includes("#"))
            url += "#root";

        let useElement = document.createElementNS(svgNamespace, "use");
        useElement.setAttributeNS(xlinkNamespace, "xlink:href", url);
        svgElement.appendChild(useElement);

        let wrapper = document.createElement("div");
        wrapper.appendChild(svgElement);

        if (className)
            wrapper.className = className;
        if (title)
            wrapper.title = title;

        return wrapper;
    }

    static promisifyLoad(src)
    {
        return new Promise((resolve, reject) => {
            let image = new Image;
            let resolveWithImage = () => { resolve(image); };
            image.addEventListener("load", resolveWithImage);
            image.addEventListener("error", resolveWithImage);
            image.src = src;
        });
    }

    static scratchCanvasContext2D(callback)
    {
        if (!WI.ImageUtilities._scratchContext2D)
            WI.ImageUtilities._scratchContext2D = document.createElement("canvas").getContext("2d");

        let context = WI.ImageUtilities._scratchContext2D;

        context.clearRect(0, 0, context.canvas.width, context.canvas.height);
        context.save();
        callback(context);
        context.restore();
    }

    static imageFromImageBitmap(data)
    {
        console.assert(data instanceof ImageBitmap);

        let image = null;
        WI.ImageUtilities.scratchCanvasContext2D((context) => {
            context.canvas.width = data.width;
            context.canvas.height = data.height;
            context.drawImage(data, 0, 0);

            image = new Image;
            image.src = context.canvas.toDataURL();
        });
        return image;
    }

    static imageFromImageData(data)
    {
        console.assert(data instanceof ImageData);

        let image = null;
        WI.ImageUtilities.scratchCanvasContext2D((context) => {
            context.canvas.width = data.width;
            context.canvas.height = data.height;
            context.putImageData(data, 0, 0);

            image = new Image;
            image.src = context.canvas.toDataURL();
        });
        return image;
    }

    static imageFromCanvasGradient(gradient, width, height)
    {
        console.assert(gradient instanceof CanvasGradient);

        let image = null;
        WI.ImageUtilities.scratchCanvasContext2D((context) => {
            context.canvas.width = width;
            context.canvas.height = height;
            context.fillStyle = gradient;
            context.fillRect(0, 0, width, height);

            image = new Image;
            image.src = context.canvas.toDataURL();
        });
        return image;
    }

    static supportsCanvasPathDebugging()
    {
        return "getPath" in CanvasRenderingContext2D.prototype
            && "setPath" in CanvasRenderingContext2D.prototype
            && "currentX" in CanvasRenderingContext2D.prototype
            && "currentY" in CanvasRenderingContext2D.prototype;
    }
};

WI.ImageUtilities._scratchContext2D = null;