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/*
mouse.register({
down: (x, y) => {
},
move: (x, y, dx, dy) => {
},
up: (x, y) => {
},
})
*/
let fns = {
down: [],
move: [],
up: [],
}
export default {
register: (callbacks) => {
callbacks.down && fns.down.push(callbacks.down)
callbacks.move && fns.move.push(callbacks.move)
callbacks.up && fns.up.push(callbacks.up)
}
}
let x, y, dragging = false
function down(e){
x = e.pageX
y = e.pageY
dragging = true
fns.down.map(f => f(x, y))
}
function move(e){
if (!dragging) return
let dx = e.pageX - x
let dy = e.pageY - y
x = e.pageX
y = e.pageY
dragging = true
fns.move.map(f => f(x, y, dx, dy))
}
function up(e){
dragging = false
fns.up.map(f => f(x, y))
}
function touch(f){ return (e) => e.preventDefault() && f(e.touches[0]) }
document.body.addEventListener("mousedown", down)
document.body.addEventListener("mousemove", move)
document.body.addEventListener("mouseup", up)
document.body.addEventListener("touchstart", touch(down))
document.body.addEventListener("touchmove", touch(move))
document.body.addEventListener("touchup", touch(up))
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