UV/Texture Editing is where you change the textures and the UV mapping of the objects.

It has a complete image editor, including layers, effects, drawing tools, real time painting and several handy features.

In UV editing you can change the whole UV of the object, vertex by vertex, map them to specific points of the texture, and generate the UV automatically as well.

The main side panel is the Layer Manager, where the layers of the texture are organized, selected and combined.

Tools

Painting tools, which always act on the active layer.

Pointer (V): Default tool, moves and transforms the active layer without painting.
Select (S): Marks a region of pixels. Whatever comes next only applies inside it.
Brush (B): Draws with a soft edged stroke.
Pencil (P): Draws with a hard stroke, without smoothing.
Eraser (E): Erases what has already been painted.
Fill Bucket (G): Fills the area of similar color under the click.
Text (T): Creates a text layer, which stays editable afterwards.
Shape (U): Creates a shape layer, which stays editable afterwards.

With the brush, the pencil or the eraser, a floating bar appears with the size, the opacity and the color of the stroke. With text or shape, it switches to the controls of that layer, such as font, alignment, fill and outline.

The pixel tools are disabled when the active layer is a text, shape or vector layer, because those layers do not hold pixels.

Menus

File

New Texture: Creates a blank texture in the chosen size.
Import Texture: Imports an image from the computer as a texture.
Export Texture: Exports the texture to the computer. Besides the common formats, it exports to PSD with the layers kept apart, and to DDS and TGA for game engines.

Edit

Copy, Cut and Paste of pixels.
Select All: Selects the whole active layer.
Free Transform: Moves, scales and rotates the selection, or the whole layer when there is no selection.
Transform Layer: Flips or rotates only the active layer, keeping the size of the texture.
Unwrap UV: Redoes the UV mapping of the selected object.

Image

What changes the whole texture, rather than the active layer.

Resize Image...: Changes the resolution of the texture, resampling the content.
Resize Canvas...: Changes the area of the texture without resampling, anchoring the content to one of the sides.
Transform Image: Flips or rotates the whole image, with every layer together. A 90 degree rotation swaps width and height.

Adjustments

Image adjustments over the active layer, with live preview.

Brilho..., Contraste..., Saturação... and Exposição....
Níveis...: Remaps the tonal range over the histogram, with the black, midtone and white points.

Effects

Image effects over the active layer.

Escala de Cinza, Inverter Cores, Desfocar..., Nitidez... and Posterizar....
Textura: Generates the maps the material uses from the image, namely normal, displacement, ambient occlusion and specular.

Generate

Generates an image from the object itself, and not from the layer.

Noise…: Generates procedural noise, with the algorithm and parameters of your choice.
Pattern…: Generates a drawn figure, among bricks, tiles, cobblestone, honeycomb, checker, stripes, grid, dots, planks, herringbone, scales and diamond plate.
Paint Ambient Occlusion…: Calculates the occlusion on the geometry and paints the result into the texture.
Paint UV Islands: Draws the islands of the UV mapping, to serve as a guide.

View

Show Vertices: Shows the vertices of the geometry on the model beside it.
Show Wireframe: Shows the edges on top of the surface of the model beside it.
Show Pixel Grid: Shows the division between pixels in the painting area, from a certain zoom level on.