You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

373 lines
10 KiB

/**
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @flow
* @format
*/
/* eslint no-bitwise: 0 */
'use strict';
const AnimatedNode = require('./AnimatedNode');
const AnimatedWithChildren = require('./AnimatedWithChildren');
const NativeAnimatedHelper = require('../NativeAnimatedHelper');
const invariant = require('invariant');
const normalizeColor = require('../../StyleSheet/normalizeColor');
import type {PlatformConfig} from '../AnimatedPlatformConfig';
type ExtrapolateType = 'extend' | 'identity' | 'clamp';
export type InterpolationConfigType<OutputT: number | string> = $ReadOnly<{
inputRange: $ReadOnlyArray<number>,
outputRange: $ReadOnlyArray<OutputT>,
easing?: (input: number) => number,
extrapolate?: ExtrapolateType,
extrapolateLeft?: ExtrapolateType,
extrapolateRight?: ExtrapolateType,
}>;
const linear = (t: number) => t;
/**
* Very handy helper to map input ranges to output ranges with an easing
* function and custom behavior outside of the ranges.
*/
function createInterpolation<OutputT: number | string>(
config: InterpolationConfigType<OutputT>,
): (input: number) => OutputT {
if (config.outputRange && typeof config.outputRange[0] === 'string') {
return (createInterpolationFromStringOutputRange((config: any)): any);
}
const outputRange: $ReadOnlyArray<number> = (config.outputRange: any);
const inputRange = config.inputRange;
if (__DEV__) {
checkInfiniteRange('outputRange', outputRange);
checkInfiniteRange('inputRange', inputRange);
checkValidInputRange(inputRange);
invariant(
inputRange.length === outputRange.length,
'inputRange (' +
inputRange.length +
') and outputRange (' +
outputRange.length +
') must have the same length',
);
}
const easing = config.easing || linear;
let extrapolateLeft: ExtrapolateType = 'extend';
if (config.extrapolateLeft !== undefined) {
extrapolateLeft = config.extrapolateLeft;
} else if (config.extrapolate !== undefined) {
extrapolateLeft = config.extrapolate;
}
let extrapolateRight: ExtrapolateType = 'extend';
if (config.extrapolateRight !== undefined) {
extrapolateRight = config.extrapolateRight;
} else if (config.extrapolate !== undefined) {
extrapolateRight = config.extrapolate;
}
return input => {
invariant(
typeof input === 'number',
'Cannot interpolation an input which is not a number',
);
const range = findRange(input, inputRange);
return (interpolate(
input,
inputRange[range],
inputRange[range + 1],
outputRange[range],
outputRange[range + 1],
easing,
extrapolateLeft,
extrapolateRight,
): any);
};
}
function interpolate(
input: number,
inputMin: number,
inputMax: number,
outputMin: number,
outputMax: number,
easing: (input: number) => number,
extrapolateLeft: ExtrapolateType,
extrapolateRight: ExtrapolateType,
) {
let result = input;
// Extrapolate
if (result < inputMin) {
if (extrapolateLeft === 'identity') {
return result;
} else if (extrapolateLeft === 'clamp') {
result = inputMin;
} else if (extrapolateLeft === 'extend') {
// noop
}
}
if (result > inputMax) {
if (extrapolateRight === 'identity') {
return result;
} else if (extrapolateRight === 'clamp') {
result = inputMax;
} else if (extrapolateRight === 'extend') {
// noop
}
}
if (outputMin === outputMax) {
return outputMin;
}
if (inputMin === inputMax) {
if (input <= inputMin) {
return outputMin;
}
return outputMax;
}
// Input Range
if (inputMin === -Infinity) {
result = -result;
} else if (inputMax === Infinity) {
result = result - inputMin;
} else {
result = (result - inputMin) / (inputMax - inputMin);
}
// Easing
result = easing(result);
// Output Range
if (outputMin === -Infinity) {
result = -result;
} else if (outputMax === Infinity) {
result = result + outputMin;
} else {
result = result * (outputMax - outputMin) + outputMin;
}
return result;
}
function colorToRgba(input: string): string {
let normalizedColor = normalizeColor(input);
if (normalizedColor === null || typeof normalizedColor !== 'number') {
return input;
}
normalizedColor = normalizedColor || 0;
const r = (normalizedColor & 0xff000000) >>> 24;
const g = (normalizedColor & 0x00ff0000) >>> 16;
const b = (normalizedColor & 0x0000ff00) >>> 8;
const a = (normalizedColor & 0x000000ff) / 255;
return `rgba(${r}, ${g}, ${b}, ${a})`;
}
const stringShapeRegex = /[+-]?(?:\d+\.?\d*|\.\d+)(?:[eE][+-]?\d+)?/g;
/**
* Supports string shapes by extracting numbers so new values can be computed,
* and recombines those values into new strings of the same shape. Supports
* things like:
*
* rgba(123, 42, 99, 0.36) // colors
* -45deg // values with units
*/
function createInterpolationFromStringOutputRange(
config: InterpolationConfigType<string>,
): (input: number) => string {
let outputRange: Array<string> = (config.outputRange: any);
invariant(outputRange.length >= 2, 'Bad output range');
outputRange = outputRange.map(colorToRgba);
checkPattern(outputRange);
// ['rgba(0, 100, 200, 0)', 'rgba(50, 150, 250, 0.5)']
// ->
// [
// [0, 50],
// [100, 150],
// [200, 250],
// [0, 0.5],
// ]
/* $FlowFixMe[incompatible-use] (>=0.18.0): `outputRange[0].match()` can
* return `null`. Need to guard against this possibility. */
const outputRanges = outputRange[0].match(stringShapeRegex).map(() => []);
outputRange.forEach(value => {
/* $FlowFixMe[incompatible-use] (>=0.18.0): `value.match()` can return
* `null`. Need to guard against this possibility. */
value.match(stringShapeRegex).forEach((number, i) => {
outputRanges[i].push(+number);
});
});
const interpolations = outputRange[0]
.match(stringShapeRegex)
/* $FlowFixMe[incompatible-use] (>=0.18.0): `outputRange[0].match()` can
* return `null`. Need to guard against this possibility. */
/* $FlowFixMe[incompatible-call] (>=0.18.0): `outputRange[0].match()` can
* return `null`. Need to guard against this possibility. */
.map((value, i) => {
return createInterpolation({
...config,
outputRange: outputRanges[i],
});
});
// rgba requires that the r,g,b are integers.... so we want to round them, but we *dont* want to
// round the opacity (4th column).
const shouldRound = isRgbOrRgba(outputRange[0]);
return input => {
let i = 0;
// 'rgba(0, 100, 200, 0)'
// ->
// 'rgba(${interpolations[0](input)}, ${interpolations[1](input)}, ...'
return outputRange[0].replace(stringShapeRegex, () => {
let val = +interpolations[i++](input);
if (shouldRound) {
val = i < 4 ? Math.round(val) : Math.round(val * 1000) / 1000;
}
return String(val);
});
};
}
function isRgbOrRgba(range: string) {
return typeof range === 'string' && range.startsWith('rgb');
}
function checkPattern(arr: $ReadOnlyArray<string>) {
const pattern = arr[0].replace(stringShapeRegex, '');
for (let i = 1; i < arr.length; ++i) {
invariant(
pattern === arr[i].replace(stringShapeRegex, ''),
'invalid pattern ' + arr[0] + ' and ' + arr[i],
);
}
}
function findRange(input: number, inputRange: $ReadOnlyArray<number>) {
let i;
for (i = 1; i < inputRange.length - 1; ++i) {
if (inputRange[i] >= input) {
break;
}
}
return i - 1;
}
function checkValidInputRange(arr: $ReadOnlyArray<number>) {
invariant(arr.length >= 2, 'inputRange must have at least 2 elements');
const message =
'inputRange must be monotonically non-decreasing ' + String(arr);
for (let i = 1; i < arr.length; ++i) {
invariant(arr[i] >= arr[i - 1], message);
}
}
function checkInfiniteRange(name: string, arr: $ReadOnlyArray<number>) {
invariant(arr.length >= 2, name + ' must have at least 2 elements');
invariant(
arr.length !== 2 || arr[0] !== -Infinity || arr[1] !== Infinity,
/* $FlowFixMe[incompatible-type] (>=0.13.0) - In the addition expression
* below this comment, one or both of the operands may be something that
* doesn't cleanly convert to a string, like undefined, null, and object,
* etc. If you really mean this implicit string conversion, you can do
* something like String(myThing) */
name + 'cannot be ]-infinity;+infinity[ ' + arr,
);
}
class AnimatedInterpolation<
OutputT: number | string,
> extends AnimatedWithChildren {
// Export for testing.
static __createInterpolation: (
config: InterpolationConfigType<OutputT>,
) => (input: number) => OutputT = createInterpolation;
_parent: AnimatedNode;
_config: InterpolationConfigType<OutputT>;
_interpolation: (input: number) => OutputT;
constructor(parent: AnimatedNode, config: InterpolationConfigType<OutputT>) {
super();
this._parent = parent;
this._config = config;
this._interpolation = createInterpolation(config);
}
__makeNative(platformConfig: ?PlatformConfig) {
this._parent.__makeNative(platformConfig);
super.__makeNative(platformConfig);
}
__getValue(): number | string {
const parentValue: number = this._parent.__getValue();
invariant(
typeof parentValue === 'number',
'Cannot interpolate an input which is not a number.',
);
return this._interpolation(parentValue);
}
interpolate<NewOutputT: number | string>(
config: InterpolationConfigType<NewOutputT>,
): AnimatedInterpolation<NewOutputT> {
return new AnimatedInterpolation(this, config);
}
__attach(): void {
this._parent.__addChild(this);
}
__detach(): void {
this._parent.__removeChild(this);
super.__detach();
}
__transformDataType(range: $ReadOnlyArray<OutputT>): Array<any> {
return range.map(NativeAnimatedHelper.transformDataType);
}
__getNativeConfig(): any {
if (__DEV__) {
NativeAnimatedHelper.validateInterpolation(this._config);
}
return {
inputRange: this._config.inputRange,
// Only the `outputRange` can contain strings so we don't need to transform `inputRange` here
outputRange: this.__transformDataType(this._config.outputRange),
extrapolateLeft:
this._config.extrapolateLeft || this._config.extrapolate || 'extend',
extrapolateRight:
this._config.extrapolateRight || this._config.extrapolate || 'extend',
type: 'interpolation',
};
}
}
module.exports = AnimatedInterpolation;