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Capture Ring Frame Slots: Ring allocation omits framing or one slot · case 04

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

Member previewVariant 4 · 3 implementations · 6 checks per implementation

Case contract

A capture ring holds four frame slots, each with an eight-byte generation header and image payload followed by a three-byte fence word. Frame generation maps monotonically to slot modulo capacity; byte addresses use slot, freshness uses full generation. 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": 64, "fence_address": 57, "fresh": false, "payload_bytes": 5, "read_address": 100, "read_header": 92, "read_slot": 3, "slot_pitch": 16, "write_header": 44, "write_slot": 0}`	`{"allocation_end": 108, "fence_address": 57, "fresh": false, "payload_bytes": 5, "read_address": 100, "read_header": 92, "read_slot": 3, "slot_pitch": 16, "write_header": 44, "write_slot": 0}`	Failed

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This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

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