libretro-scummvm-backend

Libretro backend for ScummVM which can be added to backends/platform folder of ScummVM base to build a Libretro core of ScummVM. The intention is be able to apply the backend without adjusting any of base ScummVM.

How to use

1. Clone official ScummVM base
2. Go to subfolder scummvm/backends/platform
3. Clone libretro-scummvm-backend to folder "libretro"
4. Go to folder scummvm/backends/platform/libretro/build
5. Compile libretro-scummvm core

Patches

Some issues cannot be fixed without making adjustments to base ScummVM. These are maintained as patches in the patches folder and can be applied before compiling if needed.

android_fix_hopkins.patch

Fixes a timing issue with fading on Android causing Hopkins FBI to crash at the title screen

android_macos_fix_ags.patch

Fixes issues with the AGS engine on Android and macOS when using -O2 and -O3 compiler performance optimization

macos_fix_androidbuilding.patch

Fixes issues with compilation for Android on macOS where input limit for commands is exceeded

macos_fix_ultima.patch

Fixes struct packing issues when compiling Ultima engine on macOS Monterey

Updating

When updating ScummVM, it's important to rebuild scummvm.zip so that any auxiliary data is bundled in. The compile the new scummvm.zip, run the following command:

cd backends/platform/libretro/aux-data
./bundle_aux_data.bash