From 6efb806cc2f4debd12dc929adb8df3aca74f20f5 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Thu, 8 Jan 2015 00:44:41 +0900
Subject: [PATCH] Stabilize FPS for JS

---
 internal/ui/ui_js.go | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/internal/ui/ui_js.go b/internal/ui/ui_js.go
index e6d7c141c..37301159b 100644
--- a/internal/ui/ui_js.go
+++ b/internal/ui/ui_js.go
@@ -21,7 +21,6 @@ import (
 	"github.com/gopherjs/webgl"
 	"github.com/hajimehoshi/ebiten/internal/opengl"
 	"strconv"
-	"time"
 )
 
 var canvas js.Object
@@ -32,7 +31,12 @@ func Use(f func(*opengl.Context)) {
 }
 
 func DoEvents() {
-	time.Sleep(0)
+	// TODO: requestAnimationFrame is not called when the window is not activated.
+	ch := make(chan struct{})
+	js.Global.Get("window").Call("requestAnimationFrame", func() {
+		close(ch)
+	})
+	<-ch
 }
 
 func Terminate() {