From 53f5928aa3cccac2526a3a28c1ab7e4603ac1b98 Mon Sep 17 00:00:00 2001
From: Tae Won Ha <h@taewon.de>
Date: Thu, 17 Nov 2016 22:51:47 +0100
Subject: [PATCH] GH-296 Better drag image

---
 VimR/Workspace/WorkspaceToolButton.swift | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/VimR/Workspace/WorkspaceToolButton.swift b/VimR/Workspace/WorkspaceToolButton.swift
index 34ae71a2..23936db6 100644
--- a/VimR/Workspace/WorkspaceToolButton.swift
+++ b/VimR/Workspace/WorkspaceToolButton.swift
@@ -152,11 +152,24 @@ extension WorkspaceToolButton {
     self.dehighlight()
   }
 
-  // https://www.raywenderlich.com/136272/drag-and-drop-tutorial-for-macos
+  // Modified version of snapshot() from https://www.raywenderlich.com/136272/drag-and-drop-tutorial-for-macos
   fileprivate func snapshot() -> NSImage {
     let pdfData = self.dataWithPDF(inside: self.bounds)
-    let image = NSImage(data: pdfData)
-    return image ?? NSImage()
+    guard let image = NSImage(data: pdfData) else {
+      return NSImage()
+    }
+
+    let result = NSImage()
+    let rect = CGRect(origin: .zero, size: image.size)
+    result.size = rect.size
+
+    result.lockFocus()
+    NSColor.controlShadowColor.set()
+    NSRectFill(rect)
+    image.draw(in: rect)
+    result.unlockFocus()
+
+    return result
   }
 }