# SPS Tree Generator

The function createTree uses the solid particle system to generate a tree. A base tree is created consisting of a trunk which forks into branches, which then themselves may fork or not. This base tree is used in two different ways.

- as the trunk and parent branches for the whole tree.
- with leaves added as a mini-tree that is added a number of times to the base trunk and parent branches to form the whole tree.

A demo can be found at: SPS Tree Generator Example

## How to use it.

Clone or copy the file https://github.com/BabylonJS/Extensions/blob/master/TreeGenerators/SPSTreeGenerator/TreeGenerator.js

call the function

`var tree = createTree(trunkHeight, trunkTaper, trunkSlices, trunkMaterial, boughs, forks, forkAngle, forkRatio, branches, branchAngle, bowFreq, bowHeight, leavesOnBranch, leafWHRatio, leafMaterial, scene);`

## Parameters

trunkHeight - height of trunk of tree. The initial trunk radius is 1 unit.

trunkTaper - fraction of starting radius for the end radius of a branch between 0 and 1.

trunkSlices - the number of points on the paths used for the ribbon mesh that forms the branch.

trunk material - the material used on all branches.

boughs - the number of times the tree will split into forked branches, 1 trunk splits into branches, 2 these branches also spilt into branches.

forks - the number of branches a branch can split into, 5 or more really slows the generation.

forkAngle - the angle a forked branch makes with its parent branch measured from the direction of the branch.

forkRatio - the ratio of the length of a branch to its parent's length, between 0 and 1.

branches - the number of mini-trees that are randomally added to the tree.

branchAngle - the angle the mini-tree makes with its parent branch from the direction of the branch.

bowFreq - the number of bows (bends) in a branch. A trunk is set to have only one bow.

bowHeight - the height of a bow from the line of direction of the branch.

leavesOnBranch - the number of leaves to be added to one side of a branch.

leafWHRatio - width to height ratio for a leaf between 0 and 1, closer to 0 longer leaf, closer to 1 more circular.

leafMaterial - material used for all leaves.

scene - BABYLON scene.

## Examples of Results for some Parameters