TerraBuilder FSX is a photo-realistic scenery designer for Microsoft Flight Simulator X. It aids scenery designer in assembling pre-saved image tiles (in BMP file format) into a single coherent photorealistic scenery, enabling user/designer to match and assemble the imagery mosaic to a high degree of accuracy. The collection of images are saved in the Microsoft Flight Simulator’s SDK INF format, and can be later re-loaded for editing and scenery compilation. TerraBuilder FSX also acts as a front-end to the resample.exe application which comes as a part of the FSX SDK and is an essential tool in creating scenery files for MS FSX.
For more information visit their website.