Window to view port coordinate clipping

In computer graphics, window-to-viewport coordinate clipping is the process of mapping and clipping 2D geometric objects defined in a window coordinate system to a viewport coordinate system.

A window is a rectangular region in the world coordinate system that defines the area of interest. A viewport is a rectangular region on the screen where the graphics are displayed. The window may be larger or smaller than the viewport, and the window may be moved and scaled relative to the viewport.

The window-to-viewport coordinate transformation involves three steps:

1. Scaling and translating the window coordinates to viewport coordinates using a transformation matrix. This involves mapping the edges of the window to the edges of the viewport. The transformation matrix can be computed based on the size and position of the window and the viewport.

2. Clipping the geometric objects to the boundaries of the viewport. This involves removing any parts of the objects that are outside the viewport. The clipping algorithm may be a simple rectangular clipping algorithm or a more complex algorithm that takes into account the shape of the objects and the viewport.

3. Mapping the clipped objects to device coordinates. This involves converting the viewport coordinates to device coordinates, which are the actual pixel locations on the screen. This is typically done using a rasterization algorithm, which assigns a color to each pixel based on the object properties, such as color, texture, and lighting.

The window-to-viewport coordinate clipping is important for displaying 2D graphics on the screen. It allows the graphics to be displayed in a rectangular region on the screen, regardless of their position and size in the world coordinate system. It also allows the graphics to be scaled and translated for different applications and devices, such as different screen sizes and resolutions.