/
index.ts
172 lines (145 loc) · 4.3 KB
/
index.ts
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
import { Driver, DriverControls } from "./types"
import { keyframes as keyframeAnimation } from "./keyframes"
import { spring } from "./spring"
import { decay } from "./decay"
import { sync, cancelSync } from "../../frameloop"
import { interpolate } from "../../utils/interpolate"
import { FrameData } from "../../frameloop/types"
import { AnimationOptions } from "../types"
const types = {
decay,
keyframes: keyframeAnimation,
tween: keyframeAnimation,
spring,
}
export function loopElapsed(elapsed: number, duration: number, delay = 0) {
return elapsed - duration - delay
}
export function reverseElapsed(
elapsed: number,
duration: number = 0,
delay = 0,
isForwardPlayback = true
) {
return isForwardPlayback
? loopElapsed(duration + -elapsed, duration, delay)
: duration - (elapsed - duration) + delay
}
export function hasRepeatDelayElapsed(
elapsed: number,
duration: number,
delay: number,
isForwardPlayback: boolean
) {
return isForwardPlayback ? elapsed >= duration + delay : elapsed <= -delay
}
const framesync: Driver = (update) => {
const passTimestamp = ({ delta }: FrameData) => update(delta)
return {
start: () => sync.update(passTimestamp, true),
stop: () => cancelSync.update(passTimestamp),
}
}
export function animate<V = number>({
duration,
driver = framesync,
elapsed = 0,
repeat: repeatMax = 0,
repeatType = "loop",
repeatDelay = 0,
keyframes,
autoplay = true,
onPlay,
onStop,
onComplete,
onRepeat,
onUpdate,
type = "keyframes",
...options
}: AnimationOptions<V>) {
let driverControls: DriverControls
let repeatCount = 0
let computedDuration: number | undefined = duration
let latest: V
let isComplete = false
let isForwardPlayback = true
let interpolateFromNumber: (t: number) => V
const animator = types[keyframes.length > 2 ? "keyframes" : type]
const origin = keyframes[0]
const target = keyframes[keyframes.length - 1]
if ((animator as any).needsInterpolation?.(origin, target)) {
interpolateFromNumber = interpolate([0, 100], [origin, target], {
clamp: false,
}) as (t: number) => V
keyframes = [0, 100] as any
}
const animation = animator({
...options,
duration,
keyframes,
} as any)
function repeat() {
repeatCount++
if (repeatType === "reverse") {
isForwardPlayback = repeatCount % 2 === 0
elapsed = reverseElapsed(
elapsed,
computedDuration,
repeatDelay,
isForwardPlayback
)
} else {
elapsed = loopElapsed(elapsed, computedDuration!, repeatDelay)
if (repeatType === "mirror") animation.flipTarget()
}
isComplete = false
onRepeat && onRepeat()
}
function complete() {
driverControls.stop()
onComplete && onComplete()
}
function update(delta: number) {
if (!isForwardPlayback) delta = -delta
elapsed += delta
if (!isComplete) {
const state = animation.next(Math.max(0, elapsed))
latest = state.value as any
if (interpolateFromNumber)
latest = interpolateFromNumber(latest as any)
isComplete = isForwardPlayback ? state.done : elapsed <= 0
}
onUpdate && onUpdate(latest)
if (isComplete) {
if (repeatCount === 0) {
computedDuration =
computedDuration !== undefined ? computedDuration : elapsed
}
if (repeatCount < repeatMax) {
hasRepeatDelayElapsed(
elapsed,
computedDuration!,
repeatDelay,
isForwardPlayback
) && repeat()
} else {
complete()
}
}
}
function play() {
onPlay && onPlay()
driverControls = driver(update)
driverControls.start()
}
autoplay && play()
return {
stop: () => {
onStop && onStop()
driverControls.stop()
},
sample: (t: number) => {
return animation.next(Math.max(0, t))
},
}
}