Portal:Portal

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The portal of portals

Portal

A portal is an opening in the walls of a building, gate or fortification, and especially a grand entrance to an important structure. Doors, metal gates or portcullis in the opening can be used to control entry or exit. The surface surrounding the opening may be made of simple building materials or decorated with ornamentation. Elements of a portal can include the voussoir, tympanum, an ornamented mullion or trumeau between doors, and columns with carvings of saints in the westwork of a church.

Portals in science fiction allow rapid travel between distant locations, often originating from some combination of natural phenomenon and technological device. These fictional devices are required for most stories on an inter-solar scale, otherwise transit time would be excessive for storytelling purposes. An advantage of portal technology over a faster-than-light drive is that it can be imagined to work instantly, and can travel to the past or future. In other forms of fiction, a portal may be magical, and connect to an alternate universe or plane of existence.

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In computer-generated imagery and real-time 3D computer graphics, portal rendering is an algorithm for visibility determination.

A game level might contain many graphical polygons; only a few of which may be visible on screen at a given time. Visibility determination allows the renderer to decide which of those fall into that category and thus reduce rendering time.

For example, in a computer game, the game area might be divided to several sectors. These sectors would be then connected to each other by small openings such as doors or windows. These openings are referred as portals. When the sector behind a portal needs to be drawn, the only parts that are visible are the parts that can be seen through the portal. Therefore, the sector can be clipped against the portal boundaries to remove overdraw.

The use of portals simplifies the game engine's task of determining visible areas and objects from any given point of view of the level, and simplifies rendering by allowing it to use each portal as a viewing frustum for the area it leads to.

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Gerald Herbert Portal (1858–1894) was a British diplomat, the Consul General for British East Africa and British Special Commissioner to Uganda. Educated at Eton, he joined the diplomatic service as an attaché in 1879, and was posted to the Egyptian Agency the same year. In 1886 he became Acting Agent and Consul General, and the following year he was sent to Ethiopia. In 1889 he was appointed to Zanzibar as the Consul General for British East Africa.

In 1892 Portal was appointed British Special Commissioner to Uganda to report to the British Government on setting up a British Protectorate to replace the East Africa Company, which was becoming increasingly ineffective amidst conflicts between rival factions, including the Kabaka (King) of Buganda, French Catholic, and British Protestant missionaries.

Portal established a settlement between the French and British Missionaries in Uganda, and on May 29, 1893 he signed a treaty with Kabaka Mwanga of Buganda. On April 1, 1893, he hauled down the flag of the British East Africa Company and hoisted the Union Jack. He returned to Britain and recommended the declaration of Uganda as a protectorate.

Portal was made Companion of the Order of the Bath in 1886, and Knights Commander of the Order of St Michael and St George in 1893. He died from typhoid fever in London on January 25, 1894, three months before his advice was acted upon. The town of Fort Portal in western Uganda, where Portal had his base, is named after him.

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Portal Apotheke SZB.jpg


Portal to the Adler Apotheke pharmacy in Schwarzenberg.

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Location of Portal, Burke County, North Daokota

Portal is a city in Burke County, North Dakota in the United States. The population was 131 at the 2000 census. Portal was founded in 1893.

Portal sits near the Canadian border and is a major port of entry for road and rail traffic. It is one of three 24-hour ports in North Dakota (the others being Dunseith and Pembina). The town is known for its "international" golf course. The ninth hole is partially in the United States and partially in Canada.

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From the depths of the gloom wherein you dwell, you do not see
much more distinctly than we the radiant and distant portals of Eden.
Only, the priests are mistaken. These holy portals are before and not behind us.

Victor Hugo, letter to the Italian translator of Les Misérables

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