ebiten/internal/clock/now_js.go

36 lines
1.0 KiB
Go

// Copyright 2016 Hajime Hoshi
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build js
package clock
import (
"syscall/js"
"time"
)
var (
jsPerformance = js.Global().Get("performance")
jsNow = jsPerformance.Get("now").Call("bind", jsPerformance)
)
func now() int64 {
// time.Now() is not reliable until GopherJS supports performance.now().
//
// performance.now is monotonic:
// https://www.w3.org/TR/hr-time-2/#sec-monotonic-clock
return int64(jsNow.Invoke().Float() * float64(time.Millisecond))
}