This simple mod creates a horizontal, vertical or stairway QR code
with the bottom left corner below the player's feet resp. in front of
the player, representing a given text.




With Cloth Config API you can use any material, else black and white concrete is used.

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Commands

• `/qr [​text`, `/vqr [​text]`, `/sqr [​text]` creates the QR code resp. `/qr [​text]` shows the usage if no text is provided
• /qrcalc [​text]` calculates the dimensions of the resulting QR code
• `/qrundo` or `/pcundo` undoes the last creation in reverse order of creation

To get examples for how to use text see https://github.com/zxing/zxing/wiki/Barcode-Contents

Using on a server

To create a QR code on a multiplayer server you'll need the permission for the `/setblock` command.

Caveat

undo works with the data received by the client. I.e. if another player modifies the same area in the meantime, undo will restore to the state at the invokation of `/qr`.
Further entities and block entities are currently NOT restored.

Dependencies

• Cloth Config API strongly recommended for more control over the mod (get the settings menu with the key `u`)