Transform rollout
Overview
In a natural distribution, trees have different orientations and sizes. With this rollout we can apply these variations to the elements.
Interface
Translation
When enabled, this value defines a random translation of the tree object over its original position. The translation come defined as a percentage of the width of the tree for X/Y and height for Z.
Note: This translation is applied after placing the tree over its position (as indicated in distribution map), so it's possible if we apply a high random translation the tree will be placed outside the area spline. If this happens, we must lower the translation value or modify the area spline until trees are placed in a good position.
Rotation
These parameters apply a random rotation over each axis. The degree of rotation ranges from Min to Max values specified (from 0 to 359 degrees).
Note: the rotation is not applied if "facing camera" checkbox is enabled in the "Camera" rollout.
Scale
Use this option to apply a random scale for each tree. It's possible to define independent ranges for XYZ, and to lock the aspect ratio with the "Lock aspect ratio" option.
Probability Curves
Lets you to define the probability of each random value in the rotation range (X axis = Min/Max range, Y axis: 0-100% probability).
Rotating to discrete values of 0º, 90º, 270º using a Probability Curve
Non-uniform scale distribution using a Probability Curve
Using Maps
The map parameter may be used to adjust the transform amounts using a texture map.
If the 'Color map' checkbox if off, the map is evaluated in monochrome mode, the white color is considered as the Max rotation value, and the black color as Min.
Turning on 'Color map', the RGB components of the image are used to define the scale for each axis, in this way: Red color-> X, Green color->Y, Blue color->Z.
If you have three monochrome scale maps, one for axis, it is easy to combine them in a unique RGB map using a Composite texture, in this way:
Probability Map
Activating this option uses a map to define a probability amount for the random range defined by the Min/Max values. Scatter objects in black areas of the map will not be randomised, objects in white areas will receive a value selected from the full range.
Using a probability map to control scale randomisation. (black = no randomisation, white = full randomisation)
Mirroring
This option flips the tree horizontally, creating a mirror image. It is useful to increase the variation of the textures without using additional maps. By default, it's applied only to trees created from templates, enable the "Use on Custom Objects" checkbox to use on custom object trees as well.