Image courtesy of
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Mike Verta (www.mikeverta.com)
.MXS
The Maxwell Render scene file format. It contains all the geometry in your scene, cameras and their settings, materials and material assignments. Note that it does not contain the actual textures used in materials or any HDR / MXI textures used in your scene.
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A standalone Maxwell material file. Note that textures used in the material are not stored inside the .MXM file, only references to the location of the textures on your computer are stored. A material can either be stored inside an .MXS file, or it can also be created by the standalone Maxwell material editor, MXED, and saved as a separate .MXM file. This can be useful to enable users yo create their own material libraries and reuse materials between scenes. .MXM files can also be extracted from an .MXS file using the function "Extract from MXS" found in the Material Editor in Maxwell Studio (Choose "File" in the Material Editor panel, then "Extract from MXS").
.MXX
Maxwell extensions. Extensions are external pieces of code that allows Maxwell perform specific tasks, like rendering fur, particles, fluid meshes, etc. They are provided with the Maxwell installation, and located inside the Maxwell 2>extensions subfolder. See the Extensions section for a detailed description.
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Same as the .STLAY file, except it stores the layout of Maxwell Render UI.
Image courtesy of Tom Rusteberg (www.wanderplay.com)