Texture mapping unit

A texture unit (english Texture Mapping Unit ( TMU ) ) is a hardware component of modern graphics cards, the textures filters for texture mapping of objects and shaders provides.

A texture unit comprises texture addressing units, which are responsible for the addressing of internal texture data, and texture filtering units which can change the data by the use of filters. In modern graphics cards more TMUs are usually incorporated directly into the graphics pipeline, while they were still separate processors in their introduction. The number of texture units is one way to make a statement about the performance of a graphics card.

The introduction of texture units meant that textures did not have to be stored in conventional RAM, but the RAM of the graphics card. The use of texture units brings a wealth Geschwindigskeitszuwachs the aperture of several textures over each other on one and the same rendering object. The reason for this is that to be textured surfaces need not be calculated for each render pass from scratch. A simple to be textured rectangle must not again be calculated and stored in the fragment buffer, provided with a texture, and then with a second rectangle that also calculated, stored, textured and then must be combined with the first rectangle. So if multiple textures units are available ( and this is supported by the application software ) that to render object from the graphics card needs to be calculated and stored only once, and the existing textures from the texture units are on the object simply sequentially applied.