Tattoo Stamp — Click to place tattoos on your avatar's skin, no cut at UV seams [VRChat / Unity / lilToon] (Free trial available)

Tattoo Stamp is a Unity editor extension for lilToon materials. Click on an avatar's skin (or clothing) in the Scene view to place tattoo or sticker images. The window can switch between English and Japanese.

Tested in VRChat: tattoos placed with this tool, including a glowing one, show up on a local test avatar (SDK Build & Test).

No avatar models are included (tool and tattoo images only).

Common problems it solves

• A lilToon decal on the skin gets cut in half at a UV seam.
• Lining up a tattoo means typing Position X / Y and Angle over and over.
• Placing a matching tattoo on the other side never quite lines up.
• Making a glowing tattoo needs a separate emission mask made in an image editor.
• You want to try it on your own avatar before buying.

What makes it different

• A Free trial: place images on your own avatar and check them in the Scene view before buying.
• Choose a white image and tick "Glow" to make it glow in your chosen color: the tool makes the glow texture and puts it into lilToon Emission (no image editor needed).
• Full version: after saving, put the mesh into the window again to get the list back, edit and re-bake (from a saved copy of the original texture, so nothing is baked twice).
• "Also place mirrored" adds a mirrored copy on the other side, no numbers to match.
• 3 tattoo designs included (black and white, 6 images; 4096 px in the Full version).

What it does

• Click to place, keep dragging to move. Shift + drag moves the selected one.
• Images are projected onto the mesh and baked, so they stay connected across UV seams (a lilToon decal can be cut at a seam).
• Each placed image stays in a list: change its position, size, rotation, color, opacity and stacking order later. Undo is included.
• "Also place mirrored" adds a mirrored copy on the opposite side.
• "Glow" makes only that image glow (lilToon Emission).
• Included: 3 tattoo designs (Moon & Moth, Heart Chain, Sakura & Waves) in black and white. Your own images work too (PNG with a transparent background; a JPG is placed with its background); white images can be tinted.

How it works

While you work, only a preview is shown in the Scene view; the original materials, textures and meshes are not changed. In the Full version, "Save and use" bakes the images into a new PNG of the original main texture, makes material copies (new files) in Assets/KotokotoLab_Output/TattooStamp, and swaps only those slots on that mesh. Glowing images also get a glow texture in the copy's Emission. One Ctrl+Z undoes the swap (the created files stay). Putting a saved mesh into the window again brings back the list, so you can edit and re-bake from a saved copy of the original texture (it does not bake on top of the baked one).

Free vs Full

• Free trial: place, preview and edit in the Scene view. It cannot save, and the included tattoo images are 512 px.
• Full: everything above plus "Save and use" (goes into your upload), with 4096 px tattoo images.

Notes

lilToon materials with a main texture only (lilToon Lite, Multi, Fur, Gem and similar kinds, materials with moving UVs or parallax, meshes whose UVs go outside a non-repeating main texture such as Wrap Mode Clamp, triangles spanning more than 1.9 UV tiles, and textures of 8192 px or more are not supported; the window shows the reason). See-through parts (cutout / transparent) still count as surfaces. If the baked texture is painted on, or Tiling / Offset is changed after saving, editing from where you left off is stopped so that change is not lost. Images go only onto surfaces of the selected mesh facing the same way as the clicked spot (where surfaces overlap, only the front one); other meshes are not taken into account. Areas sharing the same UVs show the image too. The baked texture is the same size as the original main texture, so a small texture makes the tattoo blurry. If the material already uses Emission, adding glowing images replaces the copy's emission settings only when you tick the option (removing all glowing images and saving again restores them). On avatars whose left and right sides differ, the mirrored copy may land slightly off. PC only. Meshes need Read/Write enabled. The preview appears only in the Scene view. Prefab Mode and Project prefabs are not supported. It does not change meshes or weights. Works without the VRChat SDK and Modular Avatar.

Requirements

Unity 2022.3 (tested on 2022.3.22f1) and lilToon (tested on 2.3.4), in a Linear color space project (VRChat projects use it).

How to install

1. Drag TattooStamp*.unitypackage into the Unity Project window and press Import.
2. Menu: Tools > Tattoo Stamp. The window has an "English" checkbox at the top.
3. Put a skin mesh of an avatar in your scene into the window, choose an image and click in the Scene view.

Importing the Full version over the Free trial replaces it.

Terms

Personal and commercial use are both OK. You may use textures with the included tattoo images baked in on your own avatars. Do not distribute or sell avatars or outfits that include those textures or materials in a form other people can use (including public or cloneable avatars). Do not redistribute or resell the tool itself or its tattoo images, and do not distribute the images on their own. Use at your own risk.

Questions or bug reports: please send a message through the shop.