(Painter)=
# Painter
The painter is how you change the texture of a model. It offers a few brushes, each with a specific role.

## "Fill Surface" Brush
This brush colors one surface of a model. A model is made of 1 or more surfaces. Each surface is made of 1 or more faces (triangles).

1. activate the brush
2. select a color
3. click the surface you want to color

```{figure} /_static/img/user-interface/painter.fill_surface.gif
:alt: surface filler
:name: surface-filler
:width: 80%
:align: center
```

## "Fill Model" Brush
This brushes does the same thing as the surface-fill brush, but for all surfaces of the model at once.

## Sticker Tool
This tool lets you add 2d assets to a UV-unwrapped[1] model like stickers:
```{figure} /_static/img/user-interface/painter.add_sticker.gif
:alt: adding a sticker
:name: adding-a-sticker
:width: 100%
:align: center
```

[1] a 3D resource with no UV data will not be able to receive stickers. UV unwrapping is on our backlog, but until then, use [blender](https://docs.blender.org/manual/en/latest/modeling/meshes/editing/uv.html) or another tool to [save the resource with UV data](https://youtu.be/XleO7DBm1Us).

Notice the tool shows details of the stack of stickers currenlty applied on a model when it's clicked:

```{figure} /_static/img/user-interface/painter.sticker-tool.png
:alt: sticker tool
:name: sticker-tool
:width: 80%
:align: center
```
Stickers can be shown/hidden, renamed, moved up/down the stack (higher means it's displayed "on top" of others), removed, and locked. A locked sticker cannot be manipulated.

### Manipulations
To manipulate a sticker, use the mouse:
- left press + release (without moving): select the sticker
- left click + drag: move the sticker on its surface (a sticker cannot move from its original surface to another)
- right click + drag: rotate
- mouse wheel: scale

```{figure} /_static/img/user-interface/painter.manipulate_sticker.gif
:alt: sticker manipulations
:name: sticker-manipulations
:width: 100%
:align: center
```

### Export
When exporting the asset, GAC blits all stickers onto a single texture applied to the mesh.