Draw an NSImage and then erase some parts with NSBezierPath

FROM : Michaël Villar
DATE : Mon May 26 23:17:18 2008

Hi,

What i want is to clear an NSImage (not entirely) with some 
NSBezierPath.
Here is my actual code :

[_image drawAtPoint:NSMakePoint(0, 0) fromRect:NSZeroRect 
operation:NSCompositeCopy fraction:1.0];

NSBezierPath * path;
path = [NSBezierPath bezierPath];
[path appendBezierPathWithArcWithCenter:NSMakePoint(0,0) radius:8 
startAngle:0 endAngle:360];
[[NSColor clearColor] set];
[path fill];


(If i use NSColor whiteColor, a white circle is drawed ;))