import * as scrawl from '../source/scrawl.js';
import { reportSpeed, addImageDragAndDrop, addCheckerboardBackground } from './utilities.js';import * as scrawl from '../source/scrawl.js';
import { reportSpeed, addImageDragAndDrop, addCheckerboardBackground } from './utilities.js';const canvas = scrawl.findCanvas('mycanvas');Namespacing boilerplate
const namespace = canvas.name;
const name = (n) => `${namespace}-${n}`;
scrawl.importDomImage('.flowers');Create the background
addCheckerboardBackground(scrawl, canvas, namespace);Create the filter
const myFilter = scrawl.makeFilter({
name: name('chromakey'),
method: 'chromakey',
reference: '#be81df',
opaqueAt: 0.39,
transparentAt: 0.32,
});Create the target entity
const piccy = scrawl.makePicture({
name: name('image'),
asset: 'iris',
dimensions: ['100%', '100%'],
copyDimensions: ['100%', '100%'],
filters: [name('chromakey')],
});Function to display frames-per-second data, and other information relevant to the demo
const report = reportSpeed('#reportmessage', function () {
return `
Reference color: ${dom.reference_color.style.backgroundColor}
Transparent at: ${dom.transparentAt.value}, Opaque at: ${dom.opaqueAt.value}
Opacity: ${dom.opacity.value}`;
});Create the Display cycle animation
scrawl.makeRender({
name: name('animation'),
target: canvas,
afterShow: report,
});const dom = scrawl.initializeDomInputs([
['input', 'transparentAt', '0.32'],
['input', 'opaqueAt', '0.39'],
['input', 'opacity', '1'],
['button', 'reference_selector', 'Select color using Eye Dropper API'],
['', 'reference_color'],
]);
dom.reference_color.style.backgroundColor = '#be81df';Setup form observer functionality
scrawl.makeUpdater({
event: ['input', 'change'],
origin: '.filter_control',
target: myFilter,
useNativeListener: true,
preventDefault: true,
updates: {
transparentAt: ['transparentAt', 'float'],
opaqueAt: ['opaqueAt', 'float'],
opacity: ['opacity', 'float'],
},
});Eyedropper API functionality Code taken from this Chrome Devs article
async function sampleColorFromScreen(abort) {
dom.reference_selector.setAttribute('disabled', '');
/** @ts-expect-error */
const dropper = new window.EyeDropper();
try {
const result = await dropper.open({signal: abort.signal});
const color = result.sRGBHex;
myFilter.set({ reference: color });
dom.reference_color.style.backgroundColor = color;
abort.abort();
dom.reference_selector.removeAttribute('disabled');
} catch (e) {
console.log(e);
abort.abort();
dom.reference_selector.removeAttribute('disabled');
}
}
const useEyedropper = () => {
if ('EyeDropper' in window) {
const abortController = new AbortController();
sampleColorFromScreen(abortController)
}
else {
dom.reference_selector.textContent = 'Eye Dropper API not supported by this browser';
}
};
scrawl.addNativeListener('click', useEyedropper, dom.reference_selector);addImageDragAndDrop(scrawl, canvas, `#${namespace} .assets`, piccy);console.log(scrawl.library);