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Mac OS X 10.7.4 I am drawing into an offscreen graphics context created via +[NSGraphicsContext graphicsContextWithBitmapImageRep:] . When I draw into this graphics context using the NSBezierPath class , everything works as expected. However, when I draw into this graphics context using the CGContextRef C functions , I see no results of my drawing. Nothing works. For reasons I won't get into, I really need to draw using the CGContextRef functions (rather than the Cocoa NSBezierPath class). My code sample is listed below. I am attempting to draw a simple "X". One stroke using NSBezierPath , one stroke using CGContextRef C functions. The first stroke works, the second does not. What am I doing wrong? NSRect imgRect = NSMakeRect(0.0, 0.0, 100.0, 100.0); NSSize imgSize = imgRect.size; NSBitmapImageRep *offscreenRep = [[[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL pixelsWide:imgSize.width pixelsHigh:imgSize.height bitsPerSample:8 samplesPerPixel:4 hasAlpha:YES isPlanar:NO colorSpaceName:NSDeviceRGBColorSpace bitmapFormat:NSAlphaFirstBitmapFormat bytesPerRow:0 bitsPerPixel:0] autorelease]; // set offscreen context NSGraphicsContext *g = [NSGraphicsContext graphicsContextWithBitmapImageRep:offscreenRep]; [NSGraphicsContext setCurrentContext:g]; NSImage *img = [[[NSImage alloc] initWithSize:imgSize] autorelease]; CGContextRef ctx = [g graphicsPort]; // lock and draw [img lockFocus]; // draw first stroke with Cocoa. this works! NSPoint p1 = NSMakePoint(NSMaxX(imgRect), NSMinY(imgRect)); NSPoint p2 = NSMakePoint(NSMinX(imgRect), NSMaxY(imgRect)); [NSBezierPath strokeLineFromPoint:p1 toPoint:p2]; // draw second stroke with Core Graphics. This doesn't work! CGContextBeginPath(ctx); CGContextMoveToPoint(ctx, 0.0, 0.0); CGContextAddLineToPoint(ctx, imgS

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