From fc7be5be3c2b8c8a4d1995a65136052aa3361862 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Fri, 26 Feb 2016 03:14:51 +0900
Subject: [PATCH] ui: Bug fix: monitor's size might be 0 e.g. on Linux VM

---
 internal/ui/ui_glfw.go | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/internal/ui/ui_glfw.go b/internal/ui/ui_glfw.go
index be995f2d7..009653857 100644
--- a/internal/ui/ui_glfw.go
+++ b/internal/ui/ui_glfw.go
@@ -109,10 +109,14 @@ type userInterface struct {
 
 func (u *userInterface) start(width, height, scale int, title string) (actualScale int, err error) {
 	m := glfw.GetPrimaryMonitor()
-	mw, _ := m.GetPhysicalSize()
 	v := m.GetVideoMode()
-	dpi := float64(v.Width) * 25.4 / float64(mw)
-	u.deviceScaleFactor = dpi / 96
+	mw, _ := m.GetPhysicalSize()
+	u.deviceScaleFactor = 1
+	// mw can be 0 on some environment like Linux VM
+	if 0 < mw {
+		dpi := float64(v.Width) * 25.4 / float64(mw)
+		u.deviceScaleFactor = dpi / 96
+	}
 
 	u.setScreenSize(width, height, scale)
 	u.window.SetTitle(title)