How do you draw to a CGContextRef and save as png?

Question

I've got a void that draws to a given CGContextRef that is usually supplied in the drawRect routine of a custom view however I also need to generate a CGContextRef that it can draw to that would allow me to save the resulting image as a PNG file.

Answer 1

Turns out it was pretty simple:

NSImage *toSave = [[NSImage alloc] initWithSize:CGSizeMake(600, 900)];

[toSave lockFocus];

CGContextRef context = [[NSGraphicsContext currentContext] graphicsPort];

//drawing code

[toSave unlockFocus];

NSBitmapImageRep *imgRep = [[toSave representations] objectAtIndex: 0];

NSData *data = [imgRep representationUsingType: NSPNGFileType properties: nil];

[data writeToFile: @"/path/to/file.png" atomically: NO];