fstl is a viewer for .stl files.
Here's a screenshot:
(credit to Pranav Panchal)
It is designed to quickly load and render very high-polygon models; showing 2 million triangles at 60+ FPS on a mid-range laptop.
For more details, see the project page.
Issues and pull requests are welcome; the project is under 1K lines of code and should be fairly approachable.
Copyright (c) 2014 Matthew Keeter
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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