From 4bedd52e162fe3a4ff51df1d65211757cb2e7f3f Mon Sep 17 00:00:00 2001
From: Alexander Ljungberg <aljungberg@slevenbits.com>
Date: Mon, 22 Oct 2012 15:03:32 +0100
Subject: [PATCH] `CPGraphicsContext saveGraphicsState` and
 `restoreGraphicsState`.

---
 AppKit/CPGraphicsContext.j | 35 ++++++++++++++++++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)

diff --git a/AppKit/CPGraphicsContext.j b/AppKit/CPGraphicsContext.j
index 741cca2d0..1299fdf0b 100644
--- a/AppKit/CPGraphicsContext.j
+++ b/AppKit/CPGraphicsContext.j
@@ -25,7 +25,8 @@
 @import "CGContext.j"
 
 
-var CPGraphicsContextCurrent = nil;
+var CPGraphicsContextCurrent = nil,
+    CPGraphicsContextThreadStack = nil;
 
 /*!
     @ingroup appkit
@@ -52,6 +53,28 @@ var CPGraphicsContextCurrent = nil;
     CPGraphicsContextCurrent = aGraphicsContext;
 }
 
++ (void)saveGraphicsState
+{
+    if (!CPGraphicsContextCurrent)
+        return;
+
+    if (!CPGraphicsContextThreadStack)
+        CPGraphicsContextThreadStack = [CPMutableArray array];
+
+    [CPGraphicsContextThreadStack addObject:CPGraphicsContextCurrent];
+    [CPGraphicsContextCurrent saveGraphicsState];
+}
+
++ (void)restoreGraphicsState
+{
+    var lastContext = [CPGraphicsContextThreadStack lastObject];
+    if (lastContext)
+    {
+        [lastContext restoreGraphicsState];
+        [CPGraphicsContextThreadStack removeLastObject];
+    }
+}
+
 /*!
     Creates a graphics context with a provided port.
     @param aContext the context to initialize with
@@ -99,4 +122,14 @@ var CPGraphicsContextCurrent = nil;
     return YES;
 }
 
+- (void)saveGraphicsState
+{
+    CGContextSaveGState(_graphicsPort);
+}
+
+- (void)restoreGraphicsState
+{
+    CGContextRestoreGState(_graphicsPort);
+}
+
 @end