The FS Dictionary

[Wing Nut]

Here is a list of some of the terms you may run into in FS.

[Wing Nut]

Anti-aliasing

Anti-aliasing is the process of bluring sharp edges in pictures to get rid of the jagged edges on lines. After an image is rendered, some applications automatically anti-alias images. The program looks for edges in an image, and then blurs adjacent pixels to produce a smoother edge.

In order to anti-alias an image when rendering, the computer has to take samples smaller than a pixel in order to figure out exactly where to blur and where not to. For example, if the computer finds that one pixel is on the edge of thwo objects, it then takes sub-pixel samples and checks about how many of them showed the fron obejct, and how many showed the back one. Lets say that the computer took 8 sub-samples, and 4 of them were on object one and the other 4 on object two. The computer then takes the resulting color values from the subsamples and averages them into a resulting blurred pixel, when viewed from a distance gives a smoother edge effect.

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MIP Mapping

MIP Mapping is an approach to texture mapping in which an original high-resolution texture map is scaled and filtered into multiple resolutions before it is applied to a surface. (MIP stands for the Latin multim im parvo, meaning "many things in a small space.") When a MIP Mapped texture is used in 3D rendering or real-time 3D displays, the texture can appear in full detail if it is seen in a close-up, or can be rendered quickly and smoothly from a lower MIP level when the object appears smaller or further away. MIP mapping saves processor time and improves anti-aliasing by allowing the computer to start with pre-filtered, pre-scaled textures at the most appropriate resolution for each frame. Usually, powers of 2 are used for the MIP Map levels, such that if the highest resolution were 1024x1024, the next levels would be 512x512, 256x256, 128x128, sometimes all the way down to 8x8 or 1x1 images.

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Bilinear or Trilinear Filtering

A technique used to smooth the

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Anistropic Filtering

In 3D computer graphics, anisotropic filtering (AF) is a method of enhancing the image quality of textures on surfaces that are far away and steeply angled with respect to the camera. Like bilinear and trilinear filtering it eliminates aliasing effects, but introduces less blur in the process and thus preserves more detail. Anisotropic filtering is computationally relatively expensive and has only recently become a standard feature of consumer-level graphics cards.

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Transform and Lighting

Transform and Lighting is a computing term used in computer graphics, generally used in the context of hardware acceleration ("Hardware T&L"). Transform refers to the task of converting coordinates in space, which in this case involves moving 3D objects in a virtual world and converting 3D coordinates to a 2D view. Lighting refers to the task of taking light objects in a virtual scene, and calculating the resulting colour of surrounding objects as the light falls upon them.

In modern 3D games with complex scenes and detailed lighting effects, the high number of points to be transformed and lit can be a computationally intense process, which is why newer 3D expansion cards offer acceleration. Cards with this capability are commonly referred to as a Graphics Processing Unit, or GPU.

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Hardware Rendered Lights

Flight Simulator illuminates objects using more than one light source. Think of it as a movie set where many lights can be set up around a sound stage.

Using the Hardware-Rendered Lights option, you can select how many lights you want the hardware (that is, your graphics card) to display. One light is used for the sun, and other lights are used for things like panel lighting, aircraft lights, and casting light on the surfaces of the aircraft. Experiment with this setting to find the level that works best for you. Selecting more lights may affect performance.

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Target Frame Rate

In a movie theater, the film generally runs past the projector's lens at a rate of 24 frames per second. At this speed, the human eye cannot detect the fact that the film is actually a series of rapidly changing still pictures. Like a movie, animated graphics are rendered on a computer screen one frame at a time. This happens at a high frame rate so it seems like a constant picture.

For some computers, it may be advantageous to limit the target frame rate. By limiting the upper end of the frame rate, the computer doesn't spend any more resources than it requires to render the selected frame rate. Resources not used to increase the frame rate beyond that setting can be used for other tasks like rendering clouds or drawing scenery in the distance. Experiment to find the frame rate that works best for you.