The Length Transform Element is a structure transforming element on the pipeline; it applies modifications on the length and length scale of the existing branches on a tree. Each branch on the tree is given a absolute position value between 0 and 1 depending on their position relative to their parent and on their overall hierarchical position on the tree. This absolute position value is used to interpolate a length or a length factor to apply on the branch (0 for min and 1 for max value).

## Curves

These curves are used to control the distribution of absolute positional value on its position and level components. The absolute positional value of the branch is the product of these components.

### Position Curve

The x axis of the curve indicates the position of the branch along its parent length (0 at the base, 1 at top). The y axis stands for the positional component value, by default 1 for all x values so that the evaluation of the curve gives 1 at all times (thus setting max length/factor on the branch).

### Level Curve

The x axis of the curve indicates the hierarchical position of the branch on the number of levels of the tree (0 for the root of the tree, 1 for tip branches). The y axis stands for the level component value, by default 1 for all x values so that the evaluation of the curve gives 1 at all times (thus setting max length/factor on the branch).

## Absolute Mode

The resulting length applied to the branch is result of an interpolation of the absolute positional value on the min/max length range.

### MinLength, MaxLength

Min and max limit values to use on the range to interpolate the absolute positional value of the branch; 0 takes the min length value and 1 the max length.

## Relative Mode

The resulting length applied to the branch is result of the original length value multiplied by a factor. The factor value is result of an interpolation of the absolute positional value on the min/max factor range.

### MinFactor, MaxFactor

Min and max limit values to use on the range used to interpolate the absolute positional value of the branch; 0 takes the min factor value and 1 the max factor.