In computer graphics

Computer graphics

Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer with help from specialized software and hardware....

, texture splatting is a method for combining different textures. The method works by applying an alphamap

Transparency (graphic)

Transparency is possible in a number of graphics file formats. The term transparency is used in various ways by different people, but at its simplest there is "full transparency" i.e. something that is completely invisible. Of course, only part of a graphic should be fully transparent, or there...

 to the higher levels, revealing the layers underneath where the alphamap is partially or completely transparent. The term was coined by Charles Bloom.

Optimizations

Since texture splatting is commonly used for terrain rendering

Terrain rendering

Terrain rendering covers a variety of methods of depicting real-world or imaginary world surfaces. Most common terrain rendering is the depiction of Earth's surface.It is used in various applications to give an observer a frame of reference...

 in computer games, various optimizations are required. Because the underlying principle is for each texture to have its own alpha channel, large amounts of memory

Computer memory

In computing, memory refers to the physical devices used to store programs or data on a temporary or permanent basis for use in a computer or other digital electronic device. The term primary memory is used for the information in physical systems which are fast In computing, memory refers to the...

 can easily be consumed. As a solution to this problem, multiple alpha maps can be combined into one texture using the red channel for one map, the blue for another, and so on. This effectively uses a single texture to supply alpha maps for four real-color textures. The alpha textures can also use a lower resolution than the color textures, and often the color textures can be tiled.

Terrains can also be split into chunks where each chunk can have its own textures. Say there is a certain texture on one part of the terrain that doesn’t appear anywhere else on it: it would be a waste of memory and processing time if the alpha map extended over the whole terrain if only 10% of it was actually required. If the terrain is split into chunks then the alpha map can also be split up according to the chunks and so now instead of 90% of that specific map being wasted only 20% may be.

External links

• Charles Bloom on Texture Splatting
• Texture Splatting in Direct3D
  Direct3D
  Direct3D is part of Microsoft's DirectX application programming interface . Direct3D is available for Microsoft Windows operating systems , and for other platforms through the open source software Wine. It is the base for the graphics API on the Xbox and Xbox 360 console systems...