Minecraft MER / MERS Map Packer
Build Bedrock material data with the exact MER or MERS channel contract, catch conflicts, and download the packed PNG with matching texture-set metadata.
Free workflow: local processing and 256px or 512px export are included after sign-in. Mapper+ unlocks output above 512px.
Start the browser workflow
Privacy: image decoding, archive inspection, channel processing, and package creation run in the browser.
How do Minecraft MER and MERS textures work?
Minecraft Bedrock MER stores metalness in red, emissive intensity in green, and roughness in blue. MERS adds subsurface scattering in alpha. A texture set must declare either the MER property or the MERS property, and metalness and subsurface are mutually exclusive at each pixel.
Minecraft packed-material contract
| Channel | MER meaning | MERS difference |
|---|---|---|
| Red | Metalness | Metalness; cannot overlap subsurface |
| Green | Emissive intensity | Same |
| Blue | Roughness | Same |
| Alpha | Unused | Subsurface scattering |
How to use Minecraft MER / MERS Map Packer
Add the material channels
Upload metalness, emissive, roughness, and optional subsurface images or unpack them from ZIP/MCPACK.
Choose MER or MERS
Use MER for RGB. Choose MERS only when the material requires a subsurface alpha channel.
Review overlap and dimensions
The preview reports resampling and resolves MERS metal/subsurface overlap by the documented higher-value rule.
Export texture plus metadata
Download PNG directly or ZIP containing the packed texture, texture_set JSON, channel manifest, and import README.
Minecraft MER / MERS Map Packer FAQ
Can MER and MERS both be declared?
No. One texture_set must use exactly one packed-material property.
What if metalness and subsurface overlap?
The export keeps the higher value; ties favor subsurface, matching Bedrock texture-set behavior.
Can I upload an existing MCPACK?
Yes. The local archive loader extracts supported images so you can repack them. Use the full resource-pack builder for a complete installable pack.
Is the ZIP itself installable?
The map-packer ZIP is a documented material fragment. Use Minecraft PBR Resource Pack Builder to create a root-correct MCPACK with a manifest.