704da021b0
* Change the implementation of `notify` so that it does not have a return value any more. * Get rid of the only remaning use of the return value of `notify` in the `every` function. * Have a "lock" on each round to ensure that no library or runtime calls `notify` synchronously, causing an update to happen half way through another update, ultimately leading to a dropped frame.
65 lines
1.8 KiB
JavaScript
65 lines
1.8 KiB
JavaScript
Elm.Native.Time = {};
|
|
Elm.Native.Time.make = function(elm) {
|
|
|
|
elm.Native = elm.Native || {};
|
|
elm.Native.Time = elm.Native.Time || {};
|
|
if (elm.Native.Time.values) return elm.Native.Time.values;
|
|
|
|
var Signal = Elm.Signal.make(elm);
|
|
var NS = Elm.Native.Signal.make(elm);
|
|
var Maybe = Elm.Maybe.make(elm);
|
|
var Utils = Elm.Native.Utils.make(elm);
|
|
|
|
function fpsWhen(desiredFPS, isOn) {
|
|
var msPerFrame = 1000 / desiredFPS;
|
|
var prev = Date.now(), curr = prev, diff = 0, wasOn = true;
|
|
var ticker = Signal.constant(diff);
|
|
function tick(zero) { return function() {
|
|
curr = Date.now();
|
|
diff = zero ? 0 : curr - prev;
|
|
prev = curr;
|
|
elm.notify(ticker.id, diff);
|
|
};
|
|
}
|
|
var timeoutID = 0;
|
|
function f(isOn, t) {
|
|
if (isOn) {
|
|
timeoutID = setTimeout(tick(!wasOn && isOn), msPerFrame);
|
|
} else if (wasOn) {
|
|
clearTimeout(timeoutID);
|
|
}
|
|
wasOn = isOn;
|
|
return t;
|
|
}
|
|
return A3( Signal.lift2, F2(f), isOn, ticker );
|
|
}
|
|
|
|
function every(t) {
|
|
var clock = Signal.constant(Date.now());
|
|
setInterval(function() {
|
|
elm.notify(clock.id, Date.now());
|
|
}, t);
|
|
return clock;
|
|
}
|
|
|
|
function since(t, s) {
|
|
function cmp(a,b) { return !Utils.eq(a,b); }
|
|
var dcount = Signal.count(A2(NS.delay, t, s));
|
|
return A3( Signal.lift2, F2(cmp), Signal.count(s), dcount );
|
|
}
|
|
function read(s) {
|
|
var t = Date.parse(s);
|
|
return isNaN(t) ? Maybe.Nothing : Maybe.Just(t);
|
|
}
|
|
return elm.Native.Time.values = {
|
|
fpsWhen : F2(fpsWhen),
|
|
fps : function(t) { return fpsWhen(t, Signal.constant(true)); },
|
|
every : every,
|
|
delay : NS.delay,
|
|
timestamp : NS.timestamp,
|
|
since : F2(since),
|
|
toDate : function(t) { return new window.Date(t); },
|
|
read : read
|
|
};
|
|
|
|
};
|