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'use strict';
// Each test is an array of [endpoint, midpoint, endpoint] and tests
// whether the endpoints interpolate to the same visual state as the midpoint
const transformTests = {
translate: [
['translateX(0px)', 'translateX(25px)', 'translateX(50px)'],
['translateY(0px)', 'translateY(25px)', 'translateY(50px)'],
['translateX(0%)', 'translateX(25%)', 'translateX(50%)'],
['translateY(0%)', 'translateY(25%)', 'translateY(50%)'],
['translateX(50%)', 'translate(25%, 25%)', 'translateY(50%)'],
['translateX(50%)', 'translate(25%, 25px)', 'translateY(50px)'],
['translateX(50px)', 'translateX(calc(25px + 25%))', 'translateX(50%)']
],
translateEm: [
['translateX(0em)', 'translateX(2em)', 'translateX(4em)'],
['translateX(-50px)', 'translateX(calc(2em - 25px))', 'translateX(4em)'],
['translateX(50%)', 'translateX(calc(25% - 2em))', 'translateX(-4em)']
],
rotate: [
// Rotation about named-axis.
['rotate(30deg)', 'rotate(60deg)', 'rotate(90deg)'],
['rotateX(30deg)', 'rotateX(60deg)', 'rotateX(90deg)'],
['rotateY(30deg)', 'rotateY(60deg)', 'rotateY(90deg)'],
['rotate(30deg)', 'rotate(60deg)', 'rotateZ(90deg)'],
['rotate(0deg)', 'rotate(180deg)', 'rotate(360deg)'],
// Common axis rotations.
['rotate3d(7, 8, 9, 0deg)', 'rotate3d(7, 8, 9, 45deg)', 'rotate3d(7, 8, 9, 90deg)'],
['rotate3d(1, 2, 3, 0deg)', 'rotate3d(3, 6, 9, 45deg)', 'rotate3d(2, 4, 6, 90deg)'],
// Axis is arbitrary if angle is zero. Use non-zero rotation to determine
// the rotation axis.
['rotateX(0deg)', 'rotate(45deg)', 'rotate(90deg)'],
['rotateX(90deg)', 'rotateX(45deg)', 'rotate(0deg)']
],
rotateSlerp: [
// First endpoint is the same rotation as rotateZ(0deg) but triggers SLERP
['rotateX(360deg)', 'rotateZ(45deg)', 'rotateZ(90deg)'],
// Interpolation with inverse. Second case is a common-axis case, but
// included here to group it with its equivalent SLERP test.
['rotate(45deg)', 'rotate(0deg)', 'rotate3d(0, 0, -1, 45deg)'],
['rotate(45deg)', 'rotate(0deg)', 'rotate(-45deg)'],
// Interpolate axis and angle of rotation.
// 70.5288deg = acos(1/3).
['rotateX(90deg)', 'rotate3d(1, 1, 0, 70.5288deg)', 'rotateY(90deg)'],
// Not nice analytical solution for this last one.
// (1, 1, 0, 90deg) --> (x, y, z, w) = (1/2, 1/2, 0, 1/root2)
// (0, 1, 1, 180deg) --> (x, y, z, w) = (0, 1/root2, 1/root2, 0)
// Trace of the "to" transformation matrix is -1. Requires special handling
// to ensure correctness of the quaternion.
// SLERP @0.5: (x, y, z, w) = (0.30389062997686395,
// 0.7336568918027127,
// 0.4297662618258487,
// 0.4297662618258487)
// --> rotate3d(0.3365568, 0.8125199, 0.4759632, 129.094547486deg)
['rotate3d(1, 1, 0, 90deg)',
'rotate3d(0.3365568, 0.8125199, 0.4759632, 129.094547486deg)',
'rotate3d(0, 1, 1, 180deg)'],
],
scale: [
['scaleX(0.5)', 'scaleX(0.75)', 'scaleX(1)'],
['scaleY(0.5)', 'scaleY(0.75)', 'scaleY(1)'],
['scale(0.5)', 'scale(0.75)', 'scale(1)'],
['scaleX(0.5)', 'scale(0.75)', 'scaleY(0.5)'],
['scale3d(0.5, 1, 2)', 'scale3d(0.75, 0.75, 3)', 'scale3d(1, 0.5, 4)']
],
skew: [
['skewX(0deg)', 'skewX(30deg)', 'skewX(60deg)'],
['skewY(0deg)', 'skewY(30deg)', 'skewY(60deg)'],
['skew(60deg, 0deg)', 'skew(30deg, 30deg)', 'skew(0deg, 60deg)'],
['skewX(0deg) rotate(0deg)', 'skewX(0deg) rotate(180deg)', 'skewX(0deg) rotate(360deg)'],
['skewX(0deg) rotate(0deg)', 'matrix(1, 0, 0, 1, 0, 0)', 'skewY(0deg) rotate(360deg)']
],
matrix: [
// matched matrix parameters do not collapse the values after them
['matrix(1,0,0,1,0,0) rotate(0deg)', 'matrix(1.5,0,0,1.5,0,0) rotate(180deg)', 'matrix(2,0,0,2,0,0) rotate(360deg)']
],
perspective: [
// Since perspective doesn't do anything on its own, we need to
// combine it with a transform that does.
['perspective(none) translateZ(15px)', 'perspective(none) translateZ(15px)', 'perspective(none) translateZ(15px)'],
['perspective(100px) translateZ(50px)', 'perspective(200px) translateZ(50px)', 'perspective(none) translateZ(50px)'],
['perspective(none) translateZ(15px)', 'perspective(50px) translateZ(15px)', 'perspective(25px) translateZ(15px)'],
['perspective(100px) translateZ(15px)', 'perspective(40px) translateZ(15px)', 'perspective(25px) translateZ(15px)'],
// Test that perspective is clamped to 1px.
['perspective(0.1px) translateZ(0.25px)', 'perspective(1px) translateZ(0.25px)', 'perspective(0.1px) translateZ(0.25px)'],
['perspective(0px) translateZ(0.25px)', 'perspective(1px) translateZ(0.25px)', 'perspective(0px) translateZ(0.25px)'],
['perspective(0px) translateZ(0.5px)', 'perspective(1.5px) translateZ(0.5px)', 'perspective(3px) translateZ(0.5px)'],
{ test: ['perspective(10px) translateZ(0.5px)', 'translateZ(0.5px)', 'perspective(1px) translateZ(0.5px)'], midpoint: -1 },
{ test: ['perspective(1px) translateZ(0.5px)', 'perspective(1px) translateZ(0.5px)', 'perspective(10px) translateZ(0.5px)'], midpoint: -1 }
]
};
// Initial setup, which includes properties that will be overridden to
// test invalidation.
function initialStyle(div) {
div.style.width = '180px';
div.style.height = '150px';
div.style.margin = '50px';
div.style.borderLeft = 'solid 40px blue';
div.style.backgroundColor = 'green';
div.style.willChange = 'transform';
div.style.fontSize = '30px';
}
function finalStyle(div) {
div.style.width = '80px';
div.style.height = '80px';
div.style.fontSize = '15px';
}
function styleBody(){
let body = document.body;
body.style.display = 'flex';
body.style.flexDirection = 'row';
body.style.flexWrap = 'wrap';
}
// Simulate a static image at 50% progress with a running animation.
// The easing curve has zero slope and curvature at its midpoint of 50% -> 50%.
// The timing values are chosen so as so that a delay of up to 10s will not
// cause a visual change.
const duration = 1e9;
const midpointOptions = {
easing: 'cubic-bezier(0,1,1,0)',
duration: duration,
delay: -duration/2
};
// Constant-valued animation using the ending keyframe's value.
const referenceOptions = {
easing: 'steps(1, jump-start)',
duration: duration,
delay: -duration/2
}
// Similar to midpointOptions, but to produce the interpolation result
// at -1 instead of the interpolation result at 0.5. This easing curve
// has zero slope at its midpoint of -100% (though does have curvature).
const negoneOptions = {
easing: 'cubic-bezier(0,-1,1,-2)',
duration: duration,
delay: -duration/2
};
// Indices to unpack a test case, which is in the format
// [start, midpoint, end]
const startIndex = 0;
const midIndex = 1;
const endIndex = 2;
async function createTests(tests) {
styleBody();
for (const obj of tests) {
let test = ("test" in obj) ? obj.test : obj;
let midpoint = ("midpoint" in obj) ? obj.midpoint : 0.5;
let options;
if (midpoint == 0.5) {
options = midpointOptions;
} else if (midpoint == -1) {
options = negoneOptions;
} else {
document.appendChild(document.createTextNode("unexpected midpoint " + midpoint));
}
let div = document.createElement('div');
document.body.appendChild(div);
initialStyle(div);
var anim =
div.animate({transform: [test[startIndex], test[endIndex]]}, options);
await anim.ready;
finalStyle(div); // Change size to test invalidation.
}
await new Promise(requestAnimationFrame);
await new Promise(requestAnimationFrame);
takeScreenshot();
}
// Create references using a constant-valued animation to avoid rounding and
// anti-aliasing differences between animated and non-animated pathways.
async function createRefs(tests) {
styleBody();
for (const obj of tests) {
let test = ("test" in obj) ? obj.test : obj;
let div = document.createElement('div');
document.body.appendChild(div);
initialStyle(div);
finalStyle(div);
var anim = div.animate(
{transform: ['none', test[midIndex]]},
referenceOptions);
await anim.ready;
}
await new Promise(requestAnimationFrame);
await new Promise(requestAnimationFrame);
takeScreenshot();
}