Mitsuba Renderer is a free 3D rendering engine created by Wenzel Jakob that creates realistic images like the following.
Wenzel is one of the co-authors of the seminal PBRT book, so he knows his stuff. Mitsuba uses an XML file format for the scene files that you can pass to the renderer as a command line parameter. This makes it easy for me to build a compatible XML file and get Mitsuba to render it each frame.
Here are some sample 4K images created with Visions of Chaos and rendered with Mitsuba using the constant lighting model. Constant lighting means that light is simulated hitting surfaces from all directions evenly. This means there are no shadows, but crevices within structures and corners are shaded darker because of ambient occlusion.
Using Mitsuba really gives clean, nicely shaded results and the examples above only using the most basic Mitsuba lighting/material setups. Mitsuba has handled the multi-gigabyte sized scene files with millions of spheres and/or cubes scenes with ease. All the end user needs to do is download/unzip Mitsuba and point Visions of Chaos to the main executable.
Jason.
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