HD packs

Documentation index

Location

Place packs under:

RetroArch\system\HdPacks\<content filename without extension>\

The pack entry file is hires.txt.

Compatibility

The fork supports classic Mesen/MesenCE HD-pack syntax. It also adds semantic authoring tags for large packs:

• <page>
• <watch>
• <paletteSet>
• <rect>
• <context>
• <contextTemplate>
• <route>
• <replace>

Semantic declarations are resolved during pack loading into the runtime condition/tile structures used by the renderer.

CHR identity

CHR-ROM content can be identified through mapped tile indexes. CHR-RAM content such as FDS games uses the complete 16-byte pattern data plus palette identity. This allows visually identical pattern layouts with different palettes to route to different replacement art.

Rule candidates are evaluated in stored order; the first candidate whose conditions pass is selected.

Additions

<addition> creates synthetic replacement pieces attached to a source tile. Synthetic pieces inherit the source logical object’s root and lifetime priority. They are useful for artwork extending beyond native hardware layouts, though ordinary full-sprite authoring may eventually move to an explicit object layer.

Backgrounds and parallax

Fork background extensions support:

• RepeatX
• RepeatY
• RepeatXY
• Gameplay scroll mode

Gameplay scrolling samples the active playfield rather than a fixed HUD split and unwraps the NES horizontal scroll cycle into continuous movement. Eligible lowest-priority repeating layers use the bulk strip compositor; unsupported cases automatically use the compatibility path.

Set MESENCE_HD_BULK_PARALLAX=0 for diagnostic A/B testing.

See the syntax reference and semantic rules guide.