FA-52065 / Raster memory layout / Member archive

Mip Chain Directory: Mip directory size uses entry count or texel width · case 05

The returned physical layout descriptor disagrees with the declared buffer mapping at directory_size.

Member previewVariant 5 · 3 implementations · 6 checks per implementation

Case contract

Store four mip levels consecutively. Each level uses ceil-halving, keeps dimensions at least one, has a two-byte row guard and a three-byte level header. A four-entry directory of two-byte offsets precedes all levels. Return the named intermediate layout descriptor and final address fields; all quantities are integer byte offsets unless explicitly stated.

Why this case matters

Offline raster resource, upload, readback, and storage-layout regression model.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
layout fixture 1	`{"allocation_end": 599, "directory_size": 4, "heights": [5, 3, 2, 1], "level_offsets": [4, 377, 494, 537], "level_origin": 49, "level_sizes": [373, 117, 43, 17], "payload_origin": 52, "row_pitches": [74, 38, 20, 14], "selected_size": 373, "widths": [12, 6, 3, 2]}`	`{"allocation_end": 603, "directory_size": 8, "heights": [5, 3, 2, 1], "level_offsets": [8, 381, 498, 541], "level_origin": 53, "level_sizes": [373, 117, 43, 17], "payload_origin": 56, "row_pitches": [74, 38, 20, 14], "selected_size": 373, "widths": [12, 6, 3, 2]}`	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.