Removing context as a parameter to the block.

This parameter is easy to create in the block if needed.

Also updating the read me with information about custom drawing.

INAppStoreWindow.h

@@ -64,8 +64,8 @@
  it would be a shame to have to re-invent that just to change the look. So this block can be used
  to override the default Mac App Store style titlebar drawing with your own drawing code!
  */
-typedef void (^INAppStoreWindowTitleBarDrawingBlock)(BOOL drawsAsMainWindow, CGRect drawingRect, 
-                                                     CGPathRef clippingPath, CGContextRef context);
+typedef void (^INAppStoreWindowTitleBarDrawingBlock)(BOOL drawsAsMainWindow, 
+                                                     CGRect drawingRect, CGPathRef clippingPath);
 @property (INAppStoreWindowCopy) INAppStoreWindowTitleBarDrawingBlock titleBarDrawingBlock;
 
 @end

INAppStoreWindow.m

@@ -138,15 +138,13 @@ - (void)drawRect:(NSRect)dirtyRect
     BOOL drawsAsMainWindow = ([window isMainWindow] && [[NSApplication sharedApplication] isActive]);
 
     NSRect drawingRect = [self bounds];
-    CGContextRef context = [[NSGraphicsContext currentContext] graphicsPort];
-
     if ( window.titleBarDrawingBlock ) {
         CGPathRef clippingPath = createClippingPathWithRectAndRadius(drawingRect, INCornerClipRadius);
-        CGContextAddPath(context, clippingPath);
-        CGContextClip(context);
-        window.titleBarDrawingBlock(drawsAsMainWindow, NSRectToCGRect(drawingRect), clippingPath, context);
+        window.titleBarDrawingBlock(drawsAsMainWindow, NSRectToCGRect(drawingRect), clippingPath);
         CGPathRelease(clippingPath);
     } else {
+        CGContextRef context = [[NSGraphicsContext currentContext] graphicsPort];        
+
         NSColor *startColor = nil;
         NSColor *endColor = nil;
         if (IN_RUNNING_LION) {

README.md

@@ -86,6 +86,18 @@ The left padding of the traffic lights can be adjusted with `trafficLightButtons
 
 The baseline divider can be hidden by setting `showsBaselineSeparator` to `NO`, the default value is `YES`.
 
+### Using your own drawing code
+
+A lot of time and effort has gone into making the custom titlebar in INAppStoreWindow function just right, it would be a shame to have to re-implement all this work just to draw your own custom title bar. So INAppStoreWindow has a `titleBarDrawingBlock` property that can be set to a block containing your own drawing code!
+
+```obj-c
+[self.window setTitleBarDrawingBlock:^(BOOL drawsAsMainWindow, CGRect drawingRect, CGPathRef clippingPath){
+    // Custom drawing code!    
+}];
+```
+
+This block gets passed some useful parameters like if the window is the main one(`drawsAsMainWindow`), the drawing rect of the title bar(`drawingRect`), and a pre-made clipping path with rounded corners at the top(`clippingPath`).
+
 ## Authors
 
 INAppStoreWindow is maintained by [Indragie Karunaratne](http://indragie.com) and [David Keegan](http://inscopeapps.com). Special thanks to [everyone else](https://github.com/indragiek/INAppStoreWindow/contributors) who contributed various fixes and improvements to the code.