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What is a Holodeck?

A Holodeck is a product used to save different forms of content (either furniture settings or even an entire environment), similar to 'Holodecks' used in various sci-fi television shows and movies. For Second Life purposes, a holodeck allows you to rez a large variety of rooms or scenarios in limited space. Some systems even allow the scene to be located far away from its control panel, offering the convenience of large, rez-on-demand structures without tying up a large space in your house.

A holodeck-panocube consists of photos. The picture changes on every wall, plus the floor and ceiling, making a total immersed "single" image. A regular holodeck will rezz and derezz prims such as different houses with furniture, and might rezz surrounding panocube images in addition.

A skybox is a method to easily create a background to make a computer and video games look bigger than it really is, by creating the illusion of distant three-dimensional surroundings. A skydome employs the same concept but uses either a sphere or a hemisphere instead of a cube.

Processing of 3d graphics is very costly, specifically in real-time games, and poses multiple limits. Levels have to be processed at tremendous speeds, making it difficult to render vast skyscapes in real-time. Additionally, due to the nature of computer graphics, objects at large distances suffer from floating point errors, causing levels to have strong limits on their extents.

To compensate for these problems, games often employ skyboxes. Traditionally, these are simple cubes with up to 6 different textures placed on the faces. By careful alignment, a viewer in the exact middle of the skybox will perceive the illusion of a real 3-D world around it, made up of those 6 faces. As a viewer moves through a 3-D scene, it is common for the skybox to remain stationary with respect to the viewer. This technique gives the skybox the illusion of being very far away since other objects in the scene appear to move, while the skybox does not. This imitates real life, where distant objects such as clouds, stars and even mountains appear to be stationary when the viewpoint is displaced by relatively small distances. Effectively, everything in a skybox will always appear to be infinitely distant from the viewer. This consequence of skyboxes dictates that designers should be careful not to carelessly include images of discrete objects in the textures of a skybox since the viewer may be able to perceive the inconsistencies of those objects' sizes as the scene is traversed. The source of a skybox can be any form of texture including photographs, hand-drawn images, or pre-rendered 3-D geometry. Usually, these textures are created and aligned in 6 directions, with viewing angles of 90 degrees (which covers up the 6 faces of the cube).

Known Holodeck & Panocube Products:

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