In a full lighting simulation such as provided by Radiance, the visual properties of an object start with color, but include a full set of optical charateristics, based on a material type and modifiers such as pattern and texture ...
As said by Carsten Bauer, the Radzilla author:
"RADZILLA is a port of the well known physically based ray tracer RADIANCE to the C++ programming language. The project is both aimed at gaining experience in C++ programming and software developoing in general as well as at the modification and optimization of RADIANCE for complex visualization applications (architecture/art/design etc).
Qtpfsgui is a graphical user interface that enables users to work on hdr images.
Supported operations include:
* creations of a HDR file from a set of images of a scene taken at different exposure settings
* tonemapping an HDR image into a common LDR image format (e.g jpeg or png)
* loading, saving and rotating existing HDR images
Qtpfsgui is available both for linux and windows.
An opensource library and a set of commandline tools for reading, writing, manipulating and viewing high-dynamic range (HDR) images and video frames.
All programs in the package exchange data using a simple generic file format (pfs) for HDR data. The concept of the pfstools is similar to netpbm package for low-dynamic range images.