# Mapping image
The Mapping image is a texture-like structure that maps each point on a geometry to a point on another geometry. The processors in Simplygon generate mapping images between the original models and their LODs to be able to cast all the original materials and properties to the corresponding point on the generated mesh.
The mapping images can either be used manually to lookup geometry info, or used as input to material casters.
Mapping images can be generated by the most processors by enabling the relevant MappingImageSettings, and also by using the SurfaceMapper tool.
For most cases the mapping image is based on new texture coordinates generated by the same processing object that is creating the mapping image. The image contains per pixel references to the original triangle ID and the barycentric coordinate of the corresponding point on the original object's surface.