From a1885458fbb2557afd36ab04c3bec17ab05dc820 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sat, 21 Jan 2017 05:10:10 +0900
Subject: [PATCH] graphics: imageImpl.restorable might be nil when restoring

---
 imageimpl.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/imageimpl.go b/imageimpl.go
index d03c633d3..9d5bfa7de 100644
--- a/imageimpl.go
+++ b/imageimpl.go
@@ -220,6 +220,9 @@ func (i *imageImpl) resetPixelsIfDependingOn(target *imageImpl, context *opengl.
 func (i *imageImpl) hasDependency() bool {
 	i.m.Lock()
 	defer i.m.Unlock()
+	if i.restorable == nil {
+		return false
+	}
 	return i.restorable.HasDependency()
 }