Wiktionary
n. 1 A viewing window. 2 (context computer graphics English) A typically rectangular region representing the range or area currently being viewed.
Wikipedia
A viewport is a polygon viewing region in computer graphics.
In computer graphics theory, there are two region-like notions of relevance when rendering some objects to an image. In textbook terminology, the world coordinate window is the area of interest (meaning what the user wants to visualize) in some application-specific coordinates, e.g. miles, centimeters etc.
The word window as used here should not be confused with the GUI window, i.e. the notion used in window managers. Rather it is an analogy with how a window limits what one can see outside a room.
In contrast, the viewport is an area (typically rectangular) expressed in rendering-device-specific coordinates, e.g. pixels for screen coordinates, in which the objects of interest are going to be rendered. Clipping to the world-coordinates window is usually applied to the objects before they are passed through the window-to-viewport transformation. For a 2D object, the latter transformation is simply a combination of translation and scaling, the latter not necessarily uniform. 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.
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.
In 3D computer graphics it refers to the 2D rectangle used to project the 3D scene to the position of a virtual camera. A viewport is a region of the screen used to display a portion of the total image to be shown.
In virtual desktops, the viewport is the visible portion of a 2D area which is larger than the visualization device. In web browsers, the viewport is the visible portion of the entire document. If the document is larger than the viewport, the user can shift the viewport around by scrolling.
Usage examples of "viewport".
In the lounge, Data spotted Darryl Adin sitting alone at a table near the viewports, looking out at the stars.
From behind the row of crew standing at the back, she saw Captain Hocking and Commander Singh conferring on the semicircular platform in front of the viewports.
There, Hocking, Singh, and Voris hunched frantic at stations, as the scramble of voices piped over comm, and the dock slid by the viewports in a slow crawl.
Through half-polarized viewports Kyp watched the surviving TIE fighters pull away and swoop back toward Carida.
The twin suns of the Tatoo system were hanging outside the forward viewport, a pair of white eyes blazing up from the black well of space.
It spoke in exquisite Terran, as if it had spent its formative years in an exclusive school on Deluros VIII or even Earth itself, it brushed its locks of false hair back from its reconstructed forehead, it drank dry martinis and tried to hide its expression of distaste, and, when it felt no one was watching, it turned to admire its reflection in the glass of the reinforced viewport that Tembo Laibon had inserted on one wall of the room.
His lizardlike skin looked slick and moist, and glistened in the dim light of the viewport, and his face, which was incapable of expression, bore a striking resemblance to the dragons Tembo Laibon had read about when he was a small child.
Beyond the sight of the viewport monitor, Aiyana handled the communication panel, while Arnoth sat at the weapons control with Batty on his shoulder.
Fearful that the glow of his photoreceptors would betray his presence, C-3PO stepped to one side of the evacuation bay hatch and continued to peer through the viewport at an oblique angle.
Saba activated a targeting reticle and slid it across the transparisteel viewport to a Yuuzhan Vong cruiser trailing behind the debris.
Grimes stared out of the viewports at the golden globe that was Stree, at the silver, flitting sparks that were the other ships.
The ship lights pulsed way down, cranking up the stars to laser intensity as Clio watched through the viewport.
While most of the Wraiths had been away on Mon Remonda, Kell and mechanic Cubber Daine had used laser cutters to open a large portion of the wall facing the Trench, giving it the aspect of a large viewport minus transparisteel, and had improvised additional chairs and tables out there.
As they glided toward the red-shaded sands of the plain, Firebird withdrew into a gray haze of contemplation, staring out the viewport.
A man looked back, but it was his own reflection in the viewport penna glass.