Viewport

In computer graphics theory, there are two region-like notions of relevance when rendering some objects to an image.

[1] An analogy of this transformation process based on traditional photography notions is to equate the world-clipping window with the camera settings and the variously sized prints that can be obtained from the resulting film image as possible viewports.

[2] Because the physical-device-based coordinates may not be portable from one device to another, a software abstraction layer known as normalized device coordinates is typically introduced for expressing viewports; it appears for example in the Graphical Kernel System (GKS) and later systems inspired from it.

[3] In 3D computer graphics, the viewport refers to the 2D rectangle used to project the 3D scene to the position of a virtual camera.

[4] In virtual desktops, the viewport is the visible portion of a 2D area which is larger than the visualization device.