FA-10538 / Raster compositing / Member archive
Premultiplied source over channel · case 03
Premultiplied foreground is multiplied by opacity a second time.
Case contract
Source is a premultiplied channel in [0,alpha]; destination is a normalized premultiplied channel. Return source-over premultiplied channel.
Why this case matters
A deterministic software graphics stage with explicit channel and coordinate conventions; no hardware, device profile or API behavior is inferred.
One recorded failure
Sample boundary fixtureThis sample comes from the broken implementation of a controlled reproducer.
| Boundary fixture | Actual | Expected | Outcome |
|---|---|---|---|
| fixture 1 | 0.30000000000000004 | 0.5 | Failed |
MEMBER ARCHIVE
The complete case is available to members.
This record includes three runnable implementations, regression fixtures, execution results, and source hashes.
Member access is invitation-based. Sign in with your invited account to inspect the sources.
Sign in to the archive ↗