renderChain runs a list of stages in order: stage 0 works on the loaded
sources, every later one on the output of the stage before it, so blur
after scanlines softens the scanlines rather than the photographs. The
effects themselves are untouched — none of them knows whether its input
came from disk. All stages share one Rng and run in sequence, so a seed
still reproduces the cascade byte for byte.
The sidebar grows an "Effect chain" list: add a stage from a menu built
from the registry, reorder it, remove it, and edit the selected stage's
params underneath. Each stage keeps its own values. The CLI takes the
same chain from repeated -e, with every flag going to the stage whose
effect declares it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Fills the canvas from one source, tiling it when it is smaller, then
applies a separable box blur repeated `passes` times to approximate a
gaussian. Params: radius, passes, direction and first_source, so the CLI
flags and the GUI widgets come out of the ParamSpecs as usual.
All random values (source index and crop offset) are drawn serially
before the parallel pixel work, so a seed reproduces the image exactly;
the box window clamps at both ends and the radius is clamped to the
canvas so an oversized radius cannot read out of bounds.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
