README: add a License section
Every other claim verified and left alone: all six listed files exist,
erosion_filter.inc / erosion_wrapper_glsl.h / test_erosion_parity.cpp /
terrain-diffusion all resolve, erosion_wrapper_params_from_map is real,
MAP_FLOOR_Y is at test_erosion_parity.cpp:110, and dc-terrain 156b2e4 is
the commit the anecdote blames ("tests: mirror map_dc_erosion.gd centring
its band on zero").
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
f34b282bbbaee6fe4cce9941d85b04791a7bb510
by plankatron <fleeky@gmail.com> · 2026-09-10T15:07:29.000Z