Clipping path

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In computer graphics, a clipping path is a path, or shape, used to cut out an image. Anything inside the path will be included after the clipping path is applied; anything outside the path will be omitted from the output. Applying the clipping path results in a hard edge. As an analogy, think of a cookie cutter. The shape of the cookie cutter describes the clipping path. The dough is analogous to the image the path is applied to. After the cutter is pressed in, everything outside of it is removed. The remaining image (or cookie in the analogy) has a clearly defined edge.

In many graphics display systems, the inside of the path is defined by the direction of the path. To change the sense of inside and outside for the path, reverse the direction of the path.

One common use of a clipping path is to cull objects that do not need to be rendered because they are outside the user's viewport.

Clipping planes are sometimes used in computer game graphics in order to prevent the renderer from having to calculate surfaces at an extreme distance from the player. This can result in a detraction from the realism of a game, as the player may notice that everything which is at or beyond a clearly defined distance is not rendered.