# Node Reference

Nodes make up the building blocks of a Yeti graph, each node will have any number of inputs and a single output along with at least the following parameters which are available in the Attribute Inspector. You can access this by double clicking the node.

## Parameters

Node parameters are either numeric ( float, vector, etc. ) or a string. All numeric parameters accept not just static values but also expressions, for instance you might have the length in a Grow node be `$F * 0.1` as the node is evaluated Yeti will resolve the $F variable and in this example the hair will grow as the frame changes. Please refer to the Expression Reference for more information.

Strings are handled somewhat differently, instead of expressions you can use ${VARNAME} to reference environment variables defined.

## Common Parameters

Parameter | Description
--- | ---
Name | the nodes name, this has to be a unique name to represent the node in the graph.
Group | most nodes obey the Group attribute, if a Group has previously been created via the Group node you may specify it here to limit the effect of the node to those specific points/fibres.
Evaluation | is used to control if the node is always evaluated or just during render or display

Note

If you try and name a node and it isn’t unique Yeti will automatically number the node accordingly.

## Creation Nodes

- Convert
- Grow
- Import
- Instance
- Reference
- Scatter

## Modifier Nodes

- Attribute
- Blend
- Displacement
- Group
- Merge
- Shader
- Texture
- Transform

## Fur / Hair Nodes

- Bend
- Clumping
- Comb
- Direction
- Guide
- Scraggle
- Width