F3D vs Marmoset Viewer

F3D is free software for viewing 3D data, browsing models, and generating renderings. It supports lighting and materials for realistic rendering, animations with GPU-accelerated skinning for character rigs, and visualization tasks such as CAD, Gaussian splatting, volume rendering, and scientific work. Its supported formats include VTK, STL, DICOM, STEP, OBJ, glTF, FBX, USD, IFC, and Gaussian splat files, among many others. Packages are available for Windows, macOS, Linux, and Android, and a browser viewer can open or accept dropped files and provides rendering and display controls. Developers can use a Python package, a beta JavaScript/WebAssembly package, or the libf3d C++ library with Python and Java bindings. F3D is distributed under the BSD 3-Clause License. Some capabilities have specific limits: FBX PBR materials and Alembic materials are unsupported, while Gaussian splatting requires OpenGL 4.3, which macOS does not support. Documentation also says volume rendering and HDRI need a decent GPU. Plugins can vary by package.

Marmoset Viewer is a physically based WebGL viewer for sharing interactive 3D presentations on the web. Scenes are created in Marmoset Toolbag and exported as optimized .mview packages to host or embed. Viewer supports animated scenes, refractive materials, shadowed fog, and shadow catcher objects. Developers can embed packages using a JavaScript library and embed utility; packages can also be uploaded to ArtStation, and a third-party WordPress plugin is available for uploads and embedding. A free standalone desktop app opens .mview files locally and is downloadable separately from Toolbag. The maker lists Windows, OS X, iOS, and Android support, but says Android support is less robust than Windows, OS X, and iOS. Global illumination, screen-space reflections, and ambient occlusion are not supported. Because models and textures must be sent to the browser for rendering, the maker says robust copy protection is essentially impossible. The standalone Viewer app is free, and Viewer is included with Toolbag versions 2.07 and newer. The listed format is .mview; measurement tools and annotation or markup are not available.