CGBitmapContext

CGBitmapContext is a data type in the Core Graphics framework of Apple's macOS and iOS operating systems. It is used for creating and manipulating bitmap images in memory. A bitmap context is essentially a drawing area in memory where you can draw using Quartz 2D drawing commands. This allows for the creation of images programmatically, which can then be used in various applications, such as drawing apps, image processing, or generating custom graphics.

Creating a CGBitmapContext involves specifying the size of the bitmap, the color space, the bits per pixel, and the bytes per row. The context can be initialized with an existing data buffer or a newly allocated one. Once created, the context can be used to draw paths, shapes, text, and images using Quartz 2D functions. After drawing, the bitmap data can be retrieved and used as needed.

CGBitmapContext is particularly useful for tasks that require off-screen rendering, such as generating thumbnails, applying filters to images, or creating custom graphics that need to be rendered before being displayed on the screen. It provides a flexible and powerful way to work with bitmap images in a programmatic manner, leveraging the capabilities of the Core Graphics framework.