# cgImage(forProposedRect:context:hints:) Returns a Core Graphics image object that captures the drawing of the image. ``` func cgImage(forProposedRect proposedDestRect: UnsafeMutablePointer?, context: NSGraphicsContext?, hints: [NSImageRep.HintKey : Any]?) -> CGImage? ``` ## Parameters `proposedDestRect` On input, the proposed destination rectangle for drawing the image. If `nil`, it defaults to the smallest pixel-integral rectangle containing `{{0,0}, self.size}`. The `proposedDestRect` is in user space in the reference context. On output, the `proposedDestRect` may have been altered. This is because a is necessarily pixel-integral, while an [`NSImage`](/documentation/AppKit/NSImage) is not. In order to produce a for rect `(0.5, 0.5, 4.0, 4.0)` without distortion or double-antialiasing, we may have to produce a 5x5 `CGImage` , and also inflate the `proposedDestRect` . Drawing the `CGImage` in the out-value `proposedDestRect` is the same as drawing the [`NSImage`](/documentation/AppKit/NSImage) in the in-value of proposed rect. `context` A graphics context. Can be `nil`. `hints` An optional dictionary of hints that provide more context for selecting or generating the image. See [`NSImageRep.HintKey`](/documentation/AppKit/NSImageRep/HintKey) for a summary of the possible key-value pairs. ## Return Value A . This may be an existing if one is available. If not, a new is created. ## Discussion An [`NSImage`](/documentation/AppKit/NSImage) is potentially resolution independent, and may have representations that allow it to draw well in many contexts. A is more like a single pixel-based representation. This method produces a snapshot of how the [`NSImage`](/documentation/AppKit/NSImage) would draw if it was asked to draw in the proposed rectangle in the graphics context. All input parameters are optional. They provide hints for how to choose among existing objects, or how to create one if there isn’t already a available. The parameters are only hints. This method is intended as an override point for image representation subclasses that naturally have a available. For example, [`NSBitmapImageRep`](/documentation/AppKit/NSBitmapImageRep) overrides it to return the that naturally backs the representation. You don’t need to override the method except possibly for performance, though. The [`NSImageRep`](/documentation/AppKit/NSImageRep)-level implementation will produce a by making a buffer and calling [`draw()`](/documentation/AppKit/NSImageRep/draw()). That’s likely to be the best possible implementation for reps that aren’t naturally -backed. The [`draw()`](/documentation/AppKit/NSImageRep/draw()) method remains the only method of [`NSImageRep`](/documentation/AppKit/NSImageRep) that a subclasser really needs to override. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)