yr-simd

yr-simd is a native C++ plugin/DLL for Yuri's Revenge that replaces selected ConvertClass blitters with SIMD-aware implementations.

The project targets x86 and dispatches runtime paths between Scalar, SSE2, AVX2, and AVX512.

Features

• Runtime SIMD detection with safe fallback.
• Optional max SIMD cap from INI (Vanilla, Scalar, SSE2, AVX2, AVX512).
• Hook-based integration into game startup and blitter allocation flow.
• Build configurations for Debug, DevBuild, and Release.

Repository Layout

• src/ - core code, hooks, utilities, and ConvertClass extension logic.
• src/Ext/ConvertClass/ - SIMD blitter mapping and implementations.
• scripts/ - local build/clean helper scripts.
• .github/ - CI workflows and composite build action.
• YRpp/ - required submodule dependency.

Requirements

• Windows
• Visual Studio 2022 (MSVC v143 toolset) or Build Tools with MSBuild
• Git

Clone and Submodules

Clone with submodules:

git clone --recurse-submodules <repo-url>

If already cloned:

git submodule update --init --recursive

Local Build

From repository root, use the helper scripts:

scripts\build_debug.bat
scripts\build_devbuild.bat
scripts\build_release.bat

Or call the generic wrapper:

scripts\build.bat DevBuild

Outputs are generated into configuration folders in repo root:

• Debug\
• DevBuild\
• Release\

The main binary is yr-simd.dll (and yr-simd.pdb for non-hardened/dev builds).

INI Options

Current runtime options loaded by the project:

• MaxSimdLevel from section [Debug] in RA2MD.INI
• FixTransparencyBlitters from section [General] in rules INI (INI_Rules)

SIMD Level Selection Logic

yr-simd automatically detects the best available CPU/OS SIMD level at runtime, then clamps it by MaxSimdLevel.

Selection order:

1. AVX512
2. AVX2
3. SSE2
4. Scalar

Important notes:

• AVX512 in this project means AVX512F + AVX512BW + AVX512VL (with required OS state support).
• MaxSimdLevel=Vanilla disables SIMD blitter replacement and returns vanilla game blitters.

Example:

[Debug]
MaxSimdLevel=AVX512 ; AVX512/AVX2/SSE2/Scalar/Vanilla

[General]
FixTransparencyBlitters=yes

CI

• Nightly Build workflow builds DevBuild and uploads artifacts.
• Release Build workflow builds Release, archives outputs, and uploads to GitHub release.

License

See LICENSE.md.