Upstream PR 3010 OpenGL S3TC Recycling

Upstream PR #3010 — Native S3TC uploads and GL texture recycling

Upstream work · Actionable research · Research and retired work

Current disposition — November 1, 2026

Reviewed: November 1, 2026. Fork source: b7140848 (full SHA b71408480a3a979a9c584663e1d1f400904c8bb7). Latest stable checked: v0.8.136-0-g458730bf5373, September 30, source 458730bf5373f1f0d027450fef7443e3af7a3ae1. GitHub state, branch recommendation, source presence and release availability are separate facts. See current status and release versus main.

Current field	November 1, 2026 observation
GitHub source	Upstream #3010
GitHub state / draft	Open / Yes
Current head	2e39fed36955cd7b994a702ad9bc0896bfc931bc
Originally reviewed head	2e39fed36955cd7b994a702ad9bc0896bfc931bc
Last metadata update (UTC)	2026-10-18T20:59:11Z
Head versus original review	Same recorded head; metadata/state updates do not indicate a new proposal-code head.
Current action	Follow #319 current-head border repair and stale B3/B4 diagnosis.
Fork/release availability	Native S3TC exists in the fork; #319 texture recycling remains unmerged and absent from main/stable.

Upstream remains an open draft. Native S3TC upload already exists in the fork; the independent recycling experiment is fork #319. Its current head also repairs stale GL border color after reuse. All eight original game attempts were collected, but candidate B3/B4 stale frame traces cannot qualify progress/performance. Current-head physical-GL confirmation and an attributable stale-trace diagnosis remain. Do not request ordinary collection again or transfer combined S3TC-plus-recycling percentages to recycling alone.

This refresh checked GitHub identity/state and the specific source boundaries named above. It did not rerun native games, XISO timings or integration qualification. Historical performance claims remain attached to their original heads.

Historical review — September 21, 2026

The review below is preserved as written, including its original state, head, fork baseline and proposed handoff. Its present-tense statements apply to that dated review; the current disposition above governs today’s action.

← Upstream Work

Field	Value
Upstream PR	xemu-project/xemu#3010
State at 2026-09-21 audit	Open draft
Reviewed upstream head	2e39fed36955cd7b994a702ad9bc0896bfc931bc
Last upstream update seen	2026-09-06
Reviewed upstream base	f9b14039e5bb56ae2d8f028e31e7cc19f13f7e12
Fork baseline	82d04d84bdb3de956f20c3537e1da2cece0e8da2
Relationship	Complementary compressed-layout tests
Related fork work	Mainkill1/xemu#127
Contribution priority	Medium
Upstream contact status	No comment posted by this audit.

Summary

Upstream combines native compressed uploads with OpenGL texture-object recycling. Fork #127 contributes checked compressed cubemap/mip layout cases, not object recycling.

Upstream scope

The proposal reduces texture-streaming cost through native S3TC upload and reuse of GL texture objects.

Corresponding fork work

Fork #127 fixes checked cubemap face stride. Related downstream work covers compressed mip sizing and copy alignment for tiny levels.

Difference that must remain explicit

A correct top-level texture does not qualify the mip chain, cubemap faces, or recycled-object state. Object recycling and compressed-source layout are distinct concerns.

Transferable regression and review cases

• Tiny BC mip levels retain minimum block storage.
• Every cubemap face uses checked face/mip offsets.
• Entire mip chain consistently uses compressed or expanded representation.
• Recycled objects reset dimensions, format, sampler-relevant state, and completeness.
• Native and fallback upload paths produce equivalent images.

Suggested upstream handoff

Offer #127’s cubemap/tiny-mip tests. Do not claim downstream has implemented the recycling mechanism.

Claims this page does not support

• It does not prove the upstream branch merges cleanly with current upstream.
• It does not prove a native correctness or performance result unless a linked exact-head run says so.
• It does not transfer favorable performance percentages between hardware, renderers, games, or source heads.
• It does not authorize posting a comment or review upstream.

Before sending anything upstream

• Refresh the PR state, head SHA, description, changed files, and newest review comments.
• Recheck the corresponding fork implementation on current main.
• Run or cite the narrow regression on an exact source state.
• Verify every public link and remove private paths, captures, game data, credentials, and internal logs.
• Phrase source concerns as source concerns and reproductions as reproductions.
• State the uncovered behavior and evidence limit.
• Add the posted URL and upstream response to this page.

Tracking log

Date	Upstream head	Action	Result
2026-09-21	2e39fed36955	Fork/upstream source comparison recorded	Handoff prepared; nothing posted

References

• Upstream PR #3010
• Fork repository
• Upstream Work
• Pull Request Lessons