Anisotropic Filtering nVIDIA's Accuview Antialiasing Technology supports an advanced texture-filtering technique that improves the image quality of objects that extend from the foreground of the scene deep into the background. nVidia calls this advanced visual technique Anisotropic Filtering, which provides the ability to choose the scale between a texture map and the primitive that it is projected on to. So what is texture mapping? And what is a primitive? In the simplest terms, texture mapping is a technique of projecting a 2D image (typically a bitmap) onto a 3D object. Texture mapping allows substantial increases in visual detail without significant increases in polygon count. A primitive is a basic element in graphics. Primitives can be polygons, lines, and curves which are combined in order to produce more sophisticated graphic images. In 3D graphics, the texture map for a given primitive is chosen based on the size of the primitive and the resulting scale. Ideally, the scale is 1:1, so that each pixel of a primitive receives one texel. A texel is short for Texture Element which is the base unit of a 3D graphic image. If the texture map is too large, there will be quality issues selecting the right texel, which results in an aliased image. On the other hand, if the texture map is too small, the texture mapped on to the primitive will look blocky. Anisotropic filtering
is extremely efficient especially in situations where polygons are large or
at sharp angles. It resolves these issues by forcing larger texture maps onto
primitives where image quality will be improved.
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