The run sorting moves to effects/sort_runs.hpp so both share it; Pixel sort
renders exactly as before.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Slit shift, channel split, pixel sort, corruption, shatter, warp, bit
crush and feedback: tearing bands sideways, knocking the colour planes
out of register, sorting runs of pixels, damaging blocks the way a broken
stream does, breaking the picture into shards, pushing it along a noise
field, mangling its bytes and laying it over itself again and again.
All eight are pure transforms. None needs sources, so any of them can
lead a chain, and like blur they start from a crop of a random source
when they do and photographs are loaded. canvasFromSources holds that
start once for them.
Each draws its whole plan from the rng before touching a pixel, and
pixel sort hands every line a seed of its own, so the parallel work
never decides anything. The rotations in shatter and feedback take their
sine and cosine from a short series of plain multiplications rather than
libm, so a seed lands on the same pixels whatever the machine's maths
library makes of std::sin.
The tests hold every one of them to the same things -- a seed
reproduces it, it runs without sources and as a later stage, a sliver
of a canvas does not trip it, turned right down it leaves its input
alone -- plus a check of what each actually does, and the registry now
checks that no two effects declare the same param key.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>