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+This repository contains (work-in-progress) sparse-implementations of 3D
+Projective Geometric Algebra, intended for use in computer graphics.
+
+There is an implementation based on rigidgeometricalgebra.org (`rga`), and
+there is also an implementation largely based on PGA4CS.pdf on bivector.net
+(`ega`).
+
+---
+
+There is basically complete test coverage, and most of the important operators
+have been implemented. While `rga` is in a more "complete" state compared to
+`ega` it would be possible to use either of the libraries, with the following
+caveats:
+- Some higher-level/compound operators (sandwich products, &c) do not yet have
+  their own sparse implementations;
+- there is currently no feature enabling explicit SIMD optimisations;
+- some desirable 3rd party traits do not yet have implementations (bytemuck,
+  serde, rand, mint);
+- aside from the included unit tests, to my knowledge there has been no
+  extensive use of these libraries in production code or otherwise.
+
+Other considerations:
+- While `mint` serves as a light-weight common interchange interface for
+  traditional gamedev math types, it occurs to me that (projective)
+  geometric-algebra libraries might be better served by their own interchange
+  crate; there-by allowing `ega`, `rga`, and other geometric algebra
+  implementations to co-exist.
+
+---
+
+As indicated in the `LICENSE` files of the respective projects, each library is
+distributed under permissive Apache2, MIT, and Zlib licenses; unless explicitly
+stated otherwise, any contributions you intentionally submit for inclusion in
+these works shall be licensed accordingly.