Normalmap

Heightmap for parallax mapping

Normalmap for a bowl model

Normal maps are images that store per-pixel surfaces normals directly in the RGB values of an image. They can dramatically increase object detalisation without adding more polygons. Therefore, normalmaps have a bunch fo limits and quirks.

Recommended articles on normalmaps:

• Polycount Wiki
• Normalmaps for the Technical Game Modeler

In Darkplaces Engine, normalmaps are:

• Tangent-space RGB
• OpenGL-oriented (X stores horizontal, Y vertical)
• Optionally can store alpha component which represents height that will be use for parallax mapping.

See also

• Texture