Spline Extruder
Updated: 3 Feb 2025
This node extrudes n-gon shapes along a spline.
Spline Extruder
Method #
This node generates a mesh from an input spline, by extruding a shape along the spline. The input spline can be modified via their control points, and the extruded mesh will dynamically update to match. Useful for making tubes and tunnels, as well as wires and ribbon effects.
A mesh can be used as input if it has the Object To Lines/Splines deformer. The Duplicate Spline deformer can also be used to easily draw multiple splines.
This node outputs the normal transformation and translation values, but it also outputs geometry which can be modified with Deformer nodes, or used as a mesh sources for nodes which accept mesh connections, such as the Field 3D Object Emitter or the Procedural 3D Object.
Parameters
These properties control the 3D transforms of the node. Transforms will generally be inherited by child nodes, although they can be ignored through the Inherit Transform Channels attributes.
Parameter Details Position X The objects position along the local x-axis.
Position Y The objects position along the local y-axis.
Position Z The objects position along the local z-axis.
Rotation Heading The objects rotation around the local y-axis.
Rotation Pitch The objects rotation around the local x-axis.
Rotation Bank The objects rotation around the local z-axis.
Scale X The objects scale along the local x-axis.
Scale Y The objects scale along the local y-axis.
Scale Z The objects scale along the local z-axis.
Control the inheritance of the transforms from the parent.
Parameter Details Position Toggle inheritance of the Position from the parent.
Rotation Toggle inheritance of the Rotation from the parent.
Scale Toggle inheritance of the Scale from the parent.
World Position Only Inherit the world position from the parent only, rotation and scale will be ignored. Overrides above properties.
Inherit Time Toggle inheritance of time from the parent.
These properties control the core behaviours of the node.
Parameter Details Num Spline Segments How many subdivisiones are added along the spline length during extrusion. Higher values can improve the smoothness of the curve, but increase the geometry count significantly and therefore can impact performance.
Spline Time Min The start point of the extruded mesh along the length of the spline, by a value normalised by the splines length.
Spline Time Max The end point of the extruded mesh along the length of the spline, by a value normalised by the splines length.
Spline Time Offset Offset the generated mesh by a value normalised over the splines length. When used with the Spline Time Min and Spline Time Max, can form a slice which moves along the spline.
Lock Subdivisions To Spline Time When enabled, the subdivisions along the spline will be treated as locked in place. The Spline Time Min/Max/Offset properties will not affect the subdivisions, instead the mesh topology will continually update to maintain a the existing topology. Useful for maintaining consistent polygon density, regardless of the length of the generated mesh.
Extrude Shape The shape of the extruded n-gon.
- Square : A square shape.
- Ring : A ring shape. the num radial segments parameter controls the number of segments in the ring.
- 2D Strip : A flat strip which is single-sided.
- Thickened Strip : A flat strip which is slightly extruded to be solid.
- Star : A star shape.
Num Radial Segments How many sides the extruded shape will have, in ring mode.
Radius The radius of the shape to be extruded along the spline.
Control Point Scaling Mode The method by which the scales from the interpolated control points scale the extruded spline’s extrusion from the spline.
- None : Only the radius parameter and fade controls will be used to scale the spline.
- Radius : Scale the extrusion in radius using the length of the control point’s xy scaling.
- XY : Scale the extrusion using the control point’s xy scaling.
Use Spline Colours Use the colours from the input spline to
UV Mode Controls how the generated geometrys uvs are generated along the spline.
Fade Front Duration How long the front edge fades for as a percentage of the whole spline.
Fade Back Duration How long the back edge fades for as a percentage of the whole spline.
Fade Alpha Fade the alpha values of the generates spline along its length using fade front and back duration. requires an alpha supporting blend mode.
Fade Scale Scale the radial size of the spline using the fade front and back duration.
Minimise Self-Intersections If enabled, attempts to avoid the self-intersections that occur at tight corners in the spline by pushing the vertices away from the intersecting planes.
Parameter Details Visible Control whether the node is visible or not to the scene.
Seen By Rays Allow the mesh to be seen by the raytracer. When set to 0, the mesh will still render in camera but will be ignored by any raytracing nodes.
Per Object Composite Alpha Overwrites the alpha channel beneath the object, giving simple effect of transparency. Best used when the mesh won’t overlap with other objects, as other meshes will not be seen through the mesh.
These properties add options for drawing all the edges of the mesh as lines. Useful for rendering wireframe effects.
Parameter Details Lines Visible Control whether the node is visible or not to the scene.
Lines Alpha Control the alpha value of the lines.
Colour Control the colour value of the lines.
Use Vertex Colours Colour lines based on the vertex colours of the geometry.
Thick Lines Use lines with thickness relative to their distance to the camera.
Hide Back Face Lines Hides the lines around back faces of geometry.
Lock Width Lock the line width to be consistent regardless of distance from the camera. only functions with thick lines enabled.
Thick Line Width Control the thickness of all the lines. only functions with thick lines enabled.
Show Silhouette Lines Draws lines along the edges of the object relative to the camera.
Show Normal Difference Lines Draw a line along the edges of the mesh, depending on the angle difference between their mutual faces.
Show Unshared Lines Draw lines along all edges of the shape.
Show Other Lines Show all the lines for each edge of the mesh.
Unshared Lines Weight Greater control over the alpha of the unshared lines.
Silhouette Lines Weight Greater control over the alpha of the silhouette lines.
Normal Difference Lines Weight Greater control over the alpha of the normal difference lines.
Other Lines Weight Greater control over the alpha of the other lines.
Line Normal Difference Angle Change the threshold angle between two face normals that will generate a line along their common edge. only functions with show normal lines enabled.
Line Normal Fade Sharpness How much the drawn normal lines will fade away the closer the edge angle is to the line normal difference angle.
Line Depth Bias Exaggerate the width of the lines based on the distance to the camera. not functional with lock width enabled.
Line Silhouette Fade Sharpness How much the drawn silhouette lines will fade away based on the size of the edge angle to the camera.
Preview the objects material in the viewport.
These properties control how the surface of the generated mesh reacts to light in the scene. See Materials for a breakdown of all these properties individually.
Inputs
These properties control the 3D transforms of the node. Transforms will generally be inherited by child nodes, although they can be ignored through the Inherit Transform Channels attributes.
| Parameter | Details |
|---|---|
| Position X | The objects position along the local x-axis. |
| Position Y | The objects position along the local y-axis. |
| Position Z | The objects position along the local z-axis. |
| Rotation Heading | The objects rotation around the local y-axis. |
| Rotation Pitch | The objects rotation around the local x-axis. |
| Rotation Bank | The objects rotation around the local z-axis. |
| Scale X | The objects scale along the local x-axis. |
| Scale Y | The objects scale along the local y-axis. |
| Scale Z | The objects scale along the local z-axis. |
Control the inheritance of the transforms from the parent.
| Parameter | Details |
|---|---|
| Position | Toggle inheritance of the Position from the parent. |
| Rotation | Toggle inheritance of the Rotation from the parent. |
| Scale | Toggle inheritance of the Scale from the parent. |
| World Position Only | Inherit the world position from the parent only, rotation and scale will be ignored. Overrides above properties. |
| Inherit Time | Toggle inheritance of time from the parent. |
These properties control the core behaviours of the node.
| Parameter | Details |
|---|---|
| Num Spline Segments | How many subdivisiones are added along the spline length during extrusion. Higher values can improve the smoothness of the curve, but increase the geometry count significantly and therefore can impact performance. |
| Spline Time Min | The start point of the extruded mesh along the length of the spline, by a value normalised by the splines length. |
| Spline Time Max | The end point of the extruded mesh along the length of the spline, by a value normalised by the splines length. |
| Spline Time Offset | Offset the generated mesh by a value normalised over the splines length. When used with the Spline Time Min and Spline Time Max, can form a slice which moves along the spline. |
| Lock Subdivisions To Spline Time | When enabled, the subdivisions along the spline will be treated as locked in place. The Spline Time Min/Max/Offset properties will not affect the subdivisions, instead the mesh topology will continually update to maintain a the existing topology. Useful for maintaining consistent polygon density, regardless of the length of the generated mesh. |
| Extrude Shape | The shape of the extruded n-gon.
|
| Num Radial Segments | How many sides the extruded shape will have, in ring mode. |
| Radius | The radius of the shape to be extruded along the spline. |
| Control Point Scaling Mode | The method by which the scales from the interpolated control points scale the extruded spline’s extrusion from the spline.
|
| Use Spline Colours | Use the colours from the input spline to |
| UV Mode | Controls how the generated geometrys uvs are generated along the spline. |
| Fade Front Duration | How long the front edge fades for as a percentage of the whole spline. |
| Fade Back Duration | How long the back edge fades for as a percentage of the whole spline. |
| Fade Alpha | Fade the alpha values of the generates spline along its length using fade front and back duration. requires an alpha supporting blend mode. |
| Fade Scale | Scale the radial size of the spline using the fade front and back duration. |
| Minimise Self-Intersections | If enabled, attempts to avoid the self-intersections that occur at tight corners in the spline by pushing the vertices away from the intersecting planes. |
| Parameter | Details |
|---|---|
| Visible | Control whether the node is visible or not to the scene. |
| Seen By Rays | Allow the mesh to be seen by the raytracer. When set to 0, the mesh will still render in camera but will be ignored by any raytracing nodes. |
| Per Object Composite Alpha | Overwrites the alpha channel beneath the object, giving simple effect of transparency. Best used when the mesh won’t overlap with other objects, as other meshes will not be seen through the mesh. |
These properties add options for drawing all the edges of the mesh as lines. Useful for rendering wireframe effects.
| Parameter | Details |
|---|---|
| Lines Visible | Control whether the node is visible or not to the scene. |
| Lines Alpha | Control the alpha value of the lines. |
| Colour | Control the colour value of the lines. |
| Use Vertex Colours | Colour lines based on the vertex colours of the geometry. |
| Thick Lines | Use lines with thickness relative to their distance to the camera. |
| Hide Back Face Lines | Hides the lines around back faces of geometry. |
| Lock Width | Lock the line width to be consistent regardless of distance from the camera. only functions with thick lines enabled. |
| Thick Line Width | Control the thickness of all the lines. only functions with thick lines enabled. |
| Show Silhouette Lines | Draws lines along the edges of the object relative to the camera. |
| Show Normal Difference Lines | Draw a line along the edges of the mesh, depending on the angle difference between their mutual faces. |
| Show Unshared Lines | Draw lines along all edges of the shape. |
| Show Other Lines | Show all the lines for each edge of the mesh. |
| Unshared Lines Weight | Greater control over the alpha of the unshared lines. |
| Silhouette Lines Weight | Greater control over the alpha of the silhouette lines. |
| Normal Difference Lines Weight | Greater control over the alpha of the normal difference lines. |
| Other Lines Weight | Greater control over the alpha of the other lines. |
| Line Normal Difference Angle | Change the threshold angle between two face normals that will generate a line along their common edge. only functions with show normal lines enabled. |
| Line Normal Fade Sharpness | How much the drawn normal lines will fade away the closer the edge angle is to the line normal difference angle. |
| Line Depth Bias | Exaggerate the width of the lines based on the distance to the camera. not functional with lock width enabled. |
| Line Silhouette Fade Sharpness | How much the drawn silhouette lines will fade away based on the size of the edge angle to the camera. |
Preview the objects material in the viewport.
These properties control how the surface of the generated mesh reacts to light in the scene. See Materials for a breakdown of all these properties individually.
| Name | Description | Typical Input |
|---|---|---|
| Spline Sources | Spline nodes used to draw the extrusion along. | Spline |
| Material | Override the default material with a material node. | “Materials”:ERROR: Variable not found: {TOPIC-LINK+nodes-materials-material} |
| Transform Modifiers | Apply the transforms of another node to this node. | Null |
| Target Node | Modifiy the rotations of the node to always direct the z axis towards the input. | Null |
| Local Transform Override | Apply the transforms of another node to this node, relative to its parent. | Null |