TABLE OF CONTENTS
Bend
Bend is used to bend fibres either towards or away from the surface, the reference frame of this surface can be altered by specifying new Normal and Up Vector values as well as the bend direction to vary the result.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| Parameter | Description |
|---|
| Bend | The amount of bend. |
| Bend Random | Randomize the amount of bend. |
| Bend Direction | Control the bend direction. |
| Bend Start/End | The point along the fibre where it should start/end bending. |
| Normal | An attribute used to define the surface normal, this along with the Up Vector is used to define the orientation of the bend. |
| Up Vector | The Up Vector, defaulting to Y, that can be used to control the orientation of the bend. |
Clumping
Will introduce clumps into the groom either based on neighbouring fibres or a second input fibre object that acts as the clumping points.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| 1 | Data Flow | Fibres |
| Parameter | Description |
|---|
| Weight | Overall level of clumping. |
| Weight Random | Randomize the clumping weight. |
| Clump Size | Define the rough size of the generated clumps. |
| Clump Selection | Determines if fibres will always clump or if they need to be within a lengths distance of a clump origin. |
| Base/Tip Attraction | How much the fibres will be attracted to the base/tip of a clump. |
| Attraction Bias | The attraction bias along the length of the fibre. |
| Twist | Causes the fibres to twist themselves around the clump. |
| Twist Random | Randomize the twist effect. |
| Fly Away | The higher the value the more fibres will fly away from the clump, adding a frizz effect. |
Geometry
| Parameter | Description |
|---|
| Length Handling | Depending on the configuration of your graph there are situations ( especially when using guide curves ) when a fibre is longer than a clump, this can cause stray looking hairs. Turn this to Conform If Longer will cause fibres that are longer than a clump to conform to the length of the clump. |
| Obey Weight | This will control how the output fibres will behave if Conform if Longer is true and the fibre is longer, if on the Weight parameter will be take into consideration, anything with a weight of 0 will be completely ignored thus retaining their length. |
Comb
The Comb node is used to apply the shape of a Groom to Fibres or Particles. When applied to Fibres they will be deformed to follow the shape and direction of the Groom, when applied to Particles the N attribute ( by default ) will be set to an average of the direction of the Groom.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres or Particles |
| 1 | Strands | Groom/Guide Curves |
| Parameter | Description |
|---|
| Weight | an overall weight of the effect. |
| Weight Random | Randomize the combing weight. |
| Spread | can be used to fan the fibres along the combing direction. |
Curl
Curl is used to create curls or ringlets from the input fibres, the reference frame of this surface can be altered by specifying a new Up Vector value.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| Parameter | Description |
|---|
| Curl | The amount of curl. |
| Curl Random | Used to randomize the curl on a per fibre basis. |
| Phase Random | Randomize the phase of the curl. |
| Root/Tip Curl | Control the amount of curl at the base/tip of the fibre. |
| Length | Controls the length of the actual curl, this can also be thought of as the phase of the curl. |
| Length Random | Randomize the length of the curl. |
| U/V Scale | The scale of the curl perpendicular to the fibre. |
| Maintain Length | If on, the curl will resample the fibre to ensure the length is maintained post evaluation but may shorten the appearance of the result. |
| Up Vector | The value for the up vector, by default this is the Y axis but can be a varying attribute to accommodate for issues where the surface normal is aligned with the Y axis.
|
Direction
The Direction node can be used to adjust the overall direction of Fibres, the reference frame of this surface can be altered by specifying new Normal and Up Vector values to vary the result.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| Parameter | Description |
|---|
| Weight | The amount that the fibres follow the direction. |
| Random | Randomize the direction. |
| Roll | The roll, or amount of rotation around the main axis ( defined by the Normal parameter ). |
| Inclination | The inclination, or amount of rotation around the secondary axis ( tangental to the Normal parameter ). |
| Normal | The attribute used to define the surface normal, this along with the Up Vector is used to define the frame of the direction. |
| Up Vector | The value for the up vector, by default this is the Y axis but can be a varying attribute to randomize the direction. |
Guide
The Guide node uses the incoming guide curves to deform the fibres to follow the direction/shape of the curves, most of the control for Guides are stored on the curve shapes themselves in Maya - please see Guide Curves for more information.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| 1 | Strands | Guide Curves |
| Parameter | Description |
|---|
| Weight | An overall weight of the effect. |
| Max Clump Influences | The number of input guides that should be considered for clumping/attraction. |
Motion
Motion is used to add subtle movement to fur without the need to simulate dynamics, at the moment the only effect is Wind. Depending on how this is set it can also be used to simulate fluttering leaves when instances are applied.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| Parameter | Description |
|---|
| Motion | The amount of motion. |
| Time | A time value used to evaluate the motion. |
| Scene Scale | Defines the overall scene scale, by default this is set to CM to match Maya. |
Wind
| Parameter | Description |
|---|
| Wind | The amount of wind. |
| Direction | Direction of the wind. |
| Scale | Scale of the wind. |
| Spread | How far off axis can the wind blow. |
| Falloff | Modulate the effect of the wind along the length of the fibre. |
Scraggle
The Scraggle node is used to add scraggle, or controlled noise, to the length of a fibre. This is extremely useful to break up fur silhouettes and make the groom look more organic. When Maintain Length is on Yeti will adjust the output fibres to make sure the length remains the same once deformed, otherwise it is likely that the length of the fibres may increase slightly ( in some cases this may be the desired look ).
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| Parameter | Description |
|---|
| Scraggle | The amount of scraggle. |
| Scraggle Multiplier | Used to modulate the overall scraggle value.
|
| Scraggle Random | Randomize the amount of scraggle on a per fibre basis. |
| Root/Tip Scraggle | Modulate the effect along the length of the fibres. |
| Scraggle Frequency | Controls the size of the scraggle effect ( similar to a phase ). |
| Scraggle Shift | Shifts the scraggle effect along the fibre. |
| Maintain Length | By default Yeti will try and maintain the fibres length, in some cases this could affect the silhouette of a character - toggling this off will apply the scraggle while still retaining the length from root to tip.
|
| Space | Control if the scraggle is applied using the length of the fibre as a reference space or the parameter of the fibre. |
| Distribution | Should the scraggle be uniform along the surface or randomized for each fibre. |
| Percentage | Controls how many of the fibres should have the effect applied. |
Width
The Width node is used to control the width attribute of the fibres, this is then passed to the renderer for the final output width used at rendertime. These are global scale values, so the Width Multiplier parameter should be used to reduce the width accordingly.
| Input | Type | Description |
|---|
| 0 | Data Flow | Fibres |
| 1 | Strands | Groom/Guide curves with a width attribute. |
| Parameter | Description |
|---|
| Width Multiplier | Modulates the width of the fibres.
|
| Width Random | Randomizes the width.
|
| Base/Tip Width | Control the width along the length of the fibres. |
Base/Tip Parameter
| defines where along the fibre the base and tip start/end. |
| Minimum Width | in many cases you don’t want the fibres width to reach 0 ( or a very small number ) so this parameter lets you control a minimum width, if the resulting widths are below this they will be clamped accordingly. |
