FA-53143 / Raster memory layout / Member archive

Page Split Texel Spans: Virtual texel byte address drops relocation or scanline padding · case 03

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

Member previewVariant 3 · 3 implementations · 6 checks per implementation

Case contract

Raster texels contain six bytes and may straddle 16-byte virtual pages. A virtual byte span maps through a noncontiguous physical page directory; output contains source spans and offsets for reassembling one texel. 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	`{"byte_addresses": [48, 49, 50, 51, 52, 53], "destination_offsets": [0], "first_bytes": 6, "first_page": 0, "first_physical": 48, "page_offset": 0, "remaining": 0, "second_physical": 112, "spans": [[48, 6]], "virtual_start": 0}`	`{"byte_addresses": [23, 24, 25, 26, 27, 28], "destination_offsets": [0], "first_bytes": 6, "first_page": 2, "first_physical": 23, "page_offset": 7, "remaining": 0, "second_physical": 128, "spans": [[23, 6]], "virtual_start": 39}`	Failed

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