experiment(ppu): deferred scanline rendering via per-HBlank register … - #62
Open
eduardovra wants to merge 1 commit into
Open
experiment(ppu): deferred scanline rendering via per-HBlank register …#62eduardovra wants to merge 1 commit into
eduardovra wants to merge 1 commit into
Conversation
…snapshots Captures PPU register state at each HBlank into a flat tuple snapshot instead of rendering immediately. At VBlank start, all 224 scanlines are rendered in a single burst from their snapshots. Rationale: batch rendering keeps VRAM, CGRAM cache and framebuffer hot in L3 cache, and is the prerequisite for full-frame NumPy vectorisation passes. Snapshot uses identity-check dirty tracking for CGRAM and OAM to avoid redundant copies. Benchmark results (15k frames): Mega Man X: 129.92 → 129.14 FPS (~neutral) SMW: 89.81 → 91.24 FPS (+1.6%) Net verdict: break-even to marginally positive. Complexity cost is high for the gain achieved; keeping as an experiment to enable future full-frame vectorisation.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
…snapshots
Captures PPU register state at each HBlank into a flat tuple snapshot instead of rendering immediately. At VBlank start, all 224 scanlines are rendered in a single burst from their snapshots.
Rationale: batch rendering keeps VRAM, CGRAM cache and framebuffer hot in L3 cache, and is the prerequisite for full-frame NumPy vectorisation passes. Snapshot uses identity-check dirty tracking for CGRAM and OAM to avoid redundant copies.
Benchmark results (15k frames):
Mega Man X: 129.92 → 129.14 FPS (~neutral)
SMW: 89.81 → 91.24 FPS (+1.6%)
Net verdict: break-even to marginally positive. Complexity cost is high for the gain achieved; keeping as an experiment to enable future full-frame vectorisation.