Atlas Wizard

Atlas Wizard turns a leaf atlas, an image of leaves laid out on a sheet, into separate leaf meshes that wear the atlas material. It's on the Natsura toolbar under Import, and it's the place to start with a new atlas. The other Atlas nodes are the steps it runs, for when you need control the wizard doesn't give you. Atlas Workflow covers the pipeline as a whole.

What it does

Inside, three nodes run in order: Atlas Material reads the textures and builds the material, Atlas Mesh traces each leaf's outline from the alpha, meshes it and splits the sheet into separate leaves, and Atlas Layout straightens the leaves and lays them out side by side. The output is one packed piece holding the leaves in their atlas positions, with the laid-out leaves inside as a hidden preview. In the shipped Simple Tree example it goes into the first input of a Clusters Decoration.

The first input is optional. Curves wired into it reach Atlas Mesh as the leaves' spines; the Simple Tree example wires a skeleton there.

Textures

Source Textures takes one image per channel: Colour, Alpha, Roughness, Height, Normal and Subsurface. The wizard reads each channel from its file and works none of them out from the colour, so fill in the ones you have. Colour and Alpha matter most: the leaves are cut out with the Alpha file, and their outlines are traced from it. A new wizard points at the summer birch leaves that ship with Natsura, so you see a result straight away.

Mesh Settings

Border Edge Length sets the spacing of points around each leaf's outline, and Inner Edge Length the size of the polygons inside it. Smaller values follow the silhouette more closely and cost more polygons. Threshold is the alpha value the outline is traced at.

Status

The atlas nodes are experimental, and their parameters may change.