From b53279b1e107e9854a64c9db06450b7a3e8e28d7 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sun, 25 Aug 2019 17:28:59 +0900
Subject: [PATCH] shareable: Remove InitializeGraphicsDriverState

---
 internal/shareable/shareable.go | 16 ++++++++++------
 uicontext.go                    | 14 --------------
 2 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/internal/shareable/shareable.go b/internal/shareable/shareable.go
index fdeb50e56..05d4e5960 100644
--- a/internal/shareable/shareable.go
+++ b/internal/shareable/shareable.go
@@ -145,6 +145,7 @@ var (
 	backendsM sync.Mutex
 
 	backendsOnce sync.Once
+	initOnce     sync.Once
 
 	// theBackends is a set of actually shared images.
 	theBackends = []*backend{}
@@ -583,12 +584,6 @@ func NewScreenFramebufferImage(width, height int) *Image {
 	return i
 }
 
-func InitializeGraphicsDriverState() error {
-	backendsM.Lock()
-	defer backendsM.Unlock()
-	return restorable.InitializeGraphicsDriverState()
-}
-
 func EndFrame() error {
 	backendsM.Lock()
 	restorable.ResolveStaleImages()
@@ -613,6 +608,15 @@ func BeginFrame() error {
 			backendsM.Unlock()
 		}
 	}()
+
+	var err error
+	initOnce.Do(func() {
+		err = restorable.InitializeGraphicsDriverState()
+	})
+	if err != nil {
+		return err
+	}
+
 	return restorable.RestoreIfNeeded()
 }
 
diff --git a/uicontext.go b/uicontext.go
index a19c57d09..6cb4b71a4 100644
--- a/uicontext.go
+++ b/uicontext.go
@@ -46,7 +46,6 @@ type uiContext struct {
 	screenWidth  int
 	screenHeight int
 	screenScale  float64
-	initialized  bool
 	offsetX      float64
 	offsetY      float64
 }
@@ -75,25 +74,12 @@ func (c *uiContext) SetSize(screenWidth, screenHeight int, screenScale float64)
 	c.offsetY = py0
 }
 
-func (c *uiContext) initializeIfNeeded() error {
-	if !c.initialized {
-		if err := shareable.InitializeGraphicsDriverState(); err != nil {
-			return err
-		}
-		c.initialized = true
-	}
-	return nil
-}
-
 func (c *uiContext) Update(afterFrameUpdate func()) error {
 	tps := int(MaxTPS())
 	updateCount := clock.Update(tps)
 
 	// TODO: If updateCount is 0 and vsync is disabled, swapping buffers can be skipped.
 
-	if err := c.initializeIfNeeded(); err != nil {
-		return err
-	}
 	if err := shareable.BeginFrame(); err != nil {
 		return err
 	}