The radius gains (|c|_1 + radius) 2^-20 in C# and both HLSL copies; the
doc's strictness claim leaves. TileBallEnclosesEveryRaySegment measures in
double over the r2 domain and seven extreme families with outward corner
flows, pins the radius two-sided, and counts misses per family. The noise
ball enclosure tests draw radii to 1e3.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>