Tree Output works similarly to Objects Output: for each layer it instantiates several trees of a given type at the positions prescribed by layer’s input. The only difference is that trees in this case are not the Transforms but the terrain Tree Instances.
Tree Generator input maps are stacked using the layers mode. Each layer could be selected by clicking on it. Above the layers, next to the "Layers:" label you can see layer control buttons:
Add: will add new layer atop of the selected one.
Remove: removes currently selected layer.
Up: will change the layers order by moving the selected layer up.
Down: will change the layers order by moving the selected layer down.
Each layer has these properties:
Prefab field: a prefab that will be instantiated for each input object
Rotate: will rotate an object around the Y-axis according to its rotation value set in the input object's hash.
Scale Width, Scale Height: the X/Z and Y scale axes can be toggled independently. Switching Width on and Height off will make the trees scale along X and Z axises, while Y scale will always be equal to 1, and vice versa. To scale uniform check both toggles, to disable scaling uncheck both.
Note that prefab trees that do not have LODs (i.e. those who use billboard imposters) could not be rotated or scaled. It’s not a MapMagic bug, it is the way Unity works.Possible solution. Note that while the tree is not rotated, it's collider does, so turn off rotation and scale feature if you are using imposter trees.
Color Tint: multiplies tree type with a given color.
Bend Factor: the influence of the tree to the wind zone.