Files
blockly/tests/playgrounds/screenshot.js
Maribeth Bottorff 05b47e27d9 chore: fix screenshot lint (#6056)
* chore: fix screenshot lint

* chore: remove extra space
2022-03-31 14:34:33 -07:00

111 lines
3.5 KiB
JavaScript

/**
* @license
* Copyright 2019 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @fileoverview Download screenshot.
*/
'use strict';
/**
* Convert an SVG datauri into a PNG datauri.
* @param {string} data SVG datauri.
* @param {number} width Image width.
* @param {number} height Image height.
* @param {!Function} callback Callback.
*/
function svgToPng_(data, width, height, callback) {
const canvas = document.createElement("canvas");
const context = canvas.getContext("2d");
const img = new Image();
const pixelDensity = 10;
canvas.width = width * pixelDensity;
canvas.height = height * pixelDensity;
img.onload = function() {
context.drawImage(
img, 0, 0, width, height, 0, 0, canvas.width, canvas.height);
try {
const dataUri = canvas.toDataURL('image/png');
callback(dataUri);
} catch (err) {
console.warn('Error converting the workspace svg to a png');
callback('');
}
};
img.src = data;
}
/**
* Create an SVG of the blocks on the workspace.
* @param {!Blockly.WorkspaceSvg} workspace The workspace.
* @param {!Function} callback Callback.
* @param {string=} customCss Custom CSS to append to the SVG.
*/
function workspaceToSvg_(workspace, callback, customCss) {
// Go through all text areas and set their value.
const textAreas = document.getElementsByTagName("textarea");
for (let i = 0; i < textAreas.length; i++) {
textAreas[i].innerHTML = textAreas[i].value;
}
const bBox = workspace.getBlocksBoundingBox();
const x = bBox.x || bBox.left;
const y = bBox.y || bBox.top;
const width = bBox.width || bBox.right - x;
const height = bBox.height || bBox.bottom - y;
const blockCanvas = workspace.getCanvas();
const clone = blockCanvas.cloneNode(true);
clone.removeAttribute('transform');
const svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
svg.setAttribute('xmlns', 'http://www.w3.org/2000/svg');
svg.appendChild(clone);
svg.setAttribute('viewBox',
x + ' ' + y + ' ' + width + ' ' + height);
svg.setAttribute('class', 'blocklySvg ' +
(workspace.options.renderer || 'geras') + '-renderer ' +
(workspace.getTheme ? workspace.getTheme().name + '-theme' : ''));
svg.setAttribute('width', width);
svg.setAttribute('height', height);
svg.setAttribute("style", 'background-color: transparent');
const css = [].slice.call(document.head.querySelectorAll('style'))
.filter(
(el) => /\.blocklySvg/.test(el.innerText) ||
(el.id.indexOf('blockly-') === 0))
.map((el) => el.innerText)
.join('\n');
const style = document.createElement('style');
style.innerHTML = css + '\n' + customCss;
svg.insertBefore(style, svg.firstChild);
let svgAsXML = (new XMLSerializer).serializeToString(svg);
svgAsXML = svgAsXML.replace(/&nbsp/g, '&#160');
const data = 'data:image/svg+xml,' + encodeURIComponent(svgAsXML);
svgToPng_(data, width, height, callback);
}
/* eslint-disable no-unused-vars */
/**
* Download a screenshot of the blocks on a Blockly workspace.
* @param {!Blockly.WorkspaceSvg} workspace The Blockly workspace.
*/
function downloadScreenshot(workspace) {
workspaceToSvg_(workspace, function(datauri) {
const a = document.createElement('a');
a.download = 'screenshot.png';
a.target = '_self';
a.href = datauri;
document.body.appendChild(a);
a.click();
a.parentNode.removeChild(a);
});
}
/* eslint-enable */