After Effects gives Repeater copy i the opacity Start + (End - Start) * i / Copies,
so the last copy stops one step short of End Opacity. EffectCraft reached End
Opacity at the last copy (i / (Copies - 1)). Measured in AE 2026 (case 709: 3
copies, End Opacity 40): copies at 100 / 80 / 60 % (EffectCraft 100 / 70 / 40);
the overlap of the two copies 92 % (EffectCraft 82 %). Now within 2/255 at the
sampled pixels.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The Smooth feather is three separable box passes of 2 round(0.37 F) + 1
pixels (a quadratic B-spline reaching ~1.11 F either side), fitted to
After Effects 2026 renders of feather 100, 300 and 1000 (rows, columns,
corner diagonal, case 398): max error under 1/255, where a Gaussian of
any width misses by 3/255 or more (it was sigma = F / 2). The coarse
grid for wide feathers picks the step whose three windows add up
closest to the full-resolution ones. Linear is unchanged (unmeasured).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The mask coverage was rasterised into the layer-sized buffer and then
blurred, so coverage outside the layer counted as 0: a feathered mask
past the layer edge faded at that edge, and one just outside the layer
gave nothing (the comment said the buffer grew; nothing grew it).
A feathered mask is now rasterised on a grid padded by the blur's whole
support (3 sigma + 3 for the Gaussian, the box radius for a linear
falloff), blurred there and cropped back to the buffer. Wide feathers
(sigma > 32 px) use a grid coarser per axis so the blur spans ~16 grid
pixels, which keeps the allocation near the buffer's size (feather 1000
on 1920x1080: a 160x134 grid instead of ~20 Mpx); the grid is capped,
feathers are clamped and non-finite ones ignored. Unfeathered masks and
masks inside the layer give the same coverage as before. The GPU uses
these CPU masks (adjustment footprint, masked sources): no GPU change.
Tests: case 398 of the .aep corpus rebuilt in the project model (red
solid, adjustment layer with a default Gradient Ramp, a 1920x200 mask
below the layer, feather 1000) within 3 levels of the Gaussian and
within 14 of After Effects' render; a mask right of a solid, a mask
larger than the layer (edges stay opaque), linear falloff, half
resolution, and huge or broken feathers.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
