digitalmints tools

Griddy

A macOS tile mapper for Sega Mega Drive / Genesis developers. Paint 0-9 tile values on an 8x8 grid and export data directly to your engine.

Download for macOS Donate via PayPal View on GitHub

macOS 15+ 8x8 Grid Free & MIT

Designed for retro workflows

Griddy overlays an 8x8 grid on your PNG and lets you paint per-tile values fast. It keeps your art visible while you map collision and logic layers.

Grid Painting

Ten tools (0-9) with click-drag rectangles and undo/redo.

Zoom & Pan

Pinch-zoom and smooth panning with custom scrollbars.

Multiple Tabs

Open several maps at once and switch instantly.

Drag & Drop

Drop PNG or .griddy files on the window or Dock icon.

Project Files

.griddy stores the image and grid, preserving PNG bytes.

Retro Friendly

Built around the Mega Drive 8×8 tile size.

Export formats

Generate data in the formats you already use or jump straight into Tiled.

C/H Source

Exports `const u16 NAME[ROWS][COLS]` for SGDK or custom engines.

CSV Import/Export

Readable grid data with comma separators.

TMX/TSX/PNG

Deduplicated 8x8 tileset atlas with palette-perfect PNG8 output.

Download

Download the latest macOS DMG.

Griddy for macOS

Version 1.2.0 · Compatible with macOS 15.0+.

Download for macOS

SHA-256 1d466250abbf10debd9ed49c7f27cfac4bb0ce293241e1aac8a0183e833b735d

Support the project

Griddy is free. If it helps your workflow, you can support indie tools like this.

Donate via PayPal

Install & use

Prebuilt app is the fastest way to get started. Source builds are supported too.

Pre-built app

Download the DMG.
Open it and drag Griddy.app to /Applications.
First launch: right-click, then Open.

Build from source

`git clone https://github.com/mintho/Griddy.git`
Open `Griddy.xcodeproj` in Xcode 15+.
Run the Griddy scheme (⌘R).

Notes & Contact

Quick notes before you export and share files.

PNG dimensions must be multiples of 8.
TMX export requires indexed PNGs (palette type 3).
Exported TMX, TSX, and PNG files should stay together.
Transparent color defaults to palette index 0.

Contact

info [at] digitalmints [dot] com