FA-52637 / Raster memory layout / Member archive

Sparse Resident Tile Map: Page-table update addresses physical slot instead of virtual directory entry · case 02

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

Member previewVariant 2 · 3 implementations · 6 checks per implementation

Case contract

A 4x4 tiled texture has a virtual tile directory mapping tile IDs to optional physical slots. Physical slots have two-byte tags; absent slots use a supplied fallback byte address and must not be interpreted as slot zero. 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 2	`{"address": 189, "candidate": 189, "directory_entry": 34, "local_index": 5, "physical_start": 172, "resident": true, "slot": 3, "slot_pitch": 50, "tile_columns": 3, "virtual_id": 1}`	`{"address": 189, "candidate": 189, "directory_entry": 26, "local_index": 5, "physical_start": 172, "resident": true, "slot": 3, "slot_pitch": 50, "tile_columns": 3, "virtual_id": 1}`	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.