pICP: plain Iterative Closest Point, a no-frills implementation in C++ of a simple rigid 3D registration algorithm. Easy to integrate, uses minimal dependencies.
Fast algorithms on 2 dimensional rigidity and (k,l)-sparsity matroids. M-component hypergraph, transversal on the MCT sets and redundant augmentation in O(|V|^2) time and O(|V|) memory.