Nexen v1.4.35 -- SNES Performance Blitz & TAS Editor Optimization

22 commits | 13+ issues addressed | 4,313 tests passing (3,690 C++ + 623 .NET) | Zero warnings

Nexen v1.4.35 is a deep performance optimization release targeting the SNES emulation core and TAS editor. Four phases of SNES PPU optimizations deliver faster rendering through pointer hoisting, early exits, and attribute hints. The TAS editor receives major allocation reduction, frame ViewModel reuse, and a contiguous memory buffer for movie input data. A critical CDL recorder race condition fix rounds out the stability improvements.

Highlights

🚀 Performance

SNES PPU Phase 4 - #1381

• ApplyColorMath pointer hoist + [[likely]] attribute on fast path
• PrecomputeWindowMasks switch hoist to avoid redundant dispatch
• ConvertToHiRes pointer arithmetic optimization

SNES PPU Phase 3 - #1376

• PrecomputeWindowMasks skip memset when masks unchanged
• RenderBgColor computation hoist out of inner loop
• Sprite priority early-exit for empty priority slots

SNES Phase 2 - #1366

• Multiple hot-path SNES performance improvements across rendering pipeline

SNES Memory Dispatch + CPU Inlining - #1361

• Memory access dispatch optimization for faster read/write operations
• CPU method inlining for critical execution paths

TAS Editor Batch Updates - #1340

• RangeObservableCollection.AddRange for batch MarkerEntries insertion
• ViewModel allocation reduction: lazy strings, dirty-check, button reuse, stackalloc
• Remove unnecessary ToList() in CellsPainted
• Fix duplicate SyncFrameViewModels calls

TAS Frame ViewModel Reuse - #1360

• Reuse TasFrameViewModel objects in UpdateFrames via SyncFrameViewModels
• Eliminates per-update allocation churn in the piano roll

TAS ViewModel Caching - #1359

• Cache P1Input/P2Input/Background properties in TasFrameViewModel
• Avoid redundant property recalculation on every access

Movie Input Contiguous Buffer - #1358

• Replace vector<string> with contiguous buffer for movie input data
• Improved cache locality and reduced allocation pressure

Benchmark Suite - #1308

• New 60K and 300K frame benchmarks for Movie/TAS operations
• Enables regression tracking for future performance work

🔧 Fixed

Movie/TAS Pass 3 - #1312

• InputFrame buffer management improvements
• FDS roundtrip correctness fix
• HasInput accuracy fix
• Undo helper robustness
• NexenMovie parameter handling

CDL Recorder Use-After-Free Race - #1356

• Fixed race condition in CDL recorder Stop() and InitDebugger() that could cause use-after-free crashes

📋 Issues Addressed

✅ Validation Summary

📥 Downloads

Windows

Linux

macOS (Apple Silicon)

Full Changelog: v1.4.34...v1.4.35