Quick Start

Let’s create an empty object and add Spline Former component to it

The SplineFormer component will manage the spline, its nodes and will generate meshes for renderers and colliders.

Now we need to set up SplineFormer. First SplineFormer will need a segment mesh, mesh that will be used as a part of a road that should be repeated along the spline.

Now we need a MeshFilter component to make the road visible and a MeshCollider component to make it solid and touchable.

If you are confused about using mesh filters then I'll try to explain.

MeshFilter component is a container for one resulting mesh. The MeshRenderer component uses it to draw one mesh. So the MeshFilter and the MeshRenderer components are used in pairs in most cases. You can find more info in this unity tutorial: https://unity3d.com/learn/tutorials/modules/beginner/graphics/mesh-renderers-and-filters

In SP you can set up which mesh filter to use for the output.

Let’s create another object for handling rendering and collisions separately from the spline generator.

Then we need

MeshRenderer component for drawing the road mesh

MeshFilter component for containing the road mesh

MeshCollider component for handling collisions

Now we can setup filter and collider properties in the SplineFormer component

After correct setup you should see that status of lofting group #0 changed to ‘Ready’ and interface properties are highlighted blue.

Also you should see something like this on the scene:

Let's fix it

First we need add more segments.

Second we need to change the loft direction. If you set the values as (1;0;0) the segments will line up along the x axis instead of z.

Now we need to rotate the segments on the spline. That is Loft angle property for.

To make rails less purple let’s add some material to it

Also you can notice that MeshFilter and MeshCollider properties are not empty anymore and MeshFilter changed its name.

Now let’s make the road longer and less straight.

You probably noticed that a node of the spline is a separate object which you can manipulate freely, but beside of that each node has node-specific properties and a button ‘Split’.

This button not surprisingly splits one node into two. This maneuver allows you to add new nodes in the middle of the spline easily.

Sometimes you need to add more segments or change the curvature coefficient to get more pleasant results.

To make the resulting mesh loop seamlessly use Loop checkbox

To avoid distortions prefer obtuse angles to acute

In the end you should obtain something like this

It’s visible.

It’s collidable.

It’s textured.

It’s done! Congratulations!

Adding Component

Simply add a SplineFormer component to any GameObject.

Interface

Spline Former

Lofting group - Everything you need for one resulting mesh. It contains references on source meshes and the options of the generating process.

Add Group button - Adds one empty Lofting group.

Remove button - Removes the corresponding Lofting group.

Segment Mesh - The mesh from which the segments of the resulting mesh will be made. Consider it as a middle or the main source mesh.

MeshFilter [Optional] - MeshFilter component to which the resulting mesh would be applied.

MeshCollider [Optional] - MeshCollider component to which the resulting mesh would be applied.

Interval(Start position/End position) - specifies the interval of the spline along which lofting will occur.

Save to OBJ - Saves the resulting mesh as OBJ. The button is disabled if there is no result yet.

Save to Asset - Saves the resulting mesh as Asset. The button is disabled if there is no result yet.

Caps:

Start Piece [Optional] - Source mesh which represents the start cap of the resulting mesh.

End Piece [Optional] - Source mesh which represents the end cap of the resulting mesh.

Processing:

Process Origin Normals - Enables the processing of normals in which the source mesh normals are considered as a source for the result normals. In most cases normals are important for the resulting look, but sometimes the source meshes just don't have correct normals, or they should be ignored. And the MeshCollider can definitely live without normals at all.

Process Origin Tangents - Enables the processing of tangents in which the source mesh tangents considered as a source for result tangents. Tangents are heavy values, that usually are precalculated, mostly used for the normal mapping. A lot of shaders don't need tangents. Consider disabling this option for better performance.

Weld Close Vertices - Welds close vertices. It usually eliminates annoying artifacts on seams that are caused by inaccuracy of float calculations and poor source meshes. Welding close vertices makes MeshRender look neat and MeshCollider work stable.

Welding Distance - Minimum distance between the result vertices. All vertices that are closer than welding distance will snap together.

Recalculate Normals - Uses Unity function to recalculate result normals based on the real mesh geometry. Useful when the source meshes don't have their own normals, or the normals are incorrect.

Smooth Normals - Enables simple surface smoothing. Usually the result of Recalculate Normals is pretty harsh. With Smooth Normals on the mesh generator recalculates normals for the close vertices and makes the surface look smoother, but preserves sharp edges.

Segments Count - Current count of the resulting mesh segments including the start and the end pieces. The segments are uniformly distributed along the entire distance of the lofting path.

Coefficient - The curvature coefficient. Choose that value purely by eye. Low values make the spline look more straight and sharp. High values may do weird things.

Loft Angle - The pitch angle of the resulting mesh along the lofting path. Makes the source mesh that looks like a floor to look like a wall and such things.

Loft Direction - The direction along which the lofting will be performed. Basically it’s the direction of the hole in the bead. Note that the lofting path will go through the source mesh pivot. Therefore, if you wish your caps to fit perfectly, your floor to be a floor, and there are no artifacts or glitches, consider the positions of the meshes pivots.

Quadratic Smooth - Adds quadratic curvature smoothing. Sometimes it works better with the sharp angles. Use to your taste.

Loop - Makes the result mesh looping seamlessly. Perfect for road loops.

Roller Coaster Fix - Experimental fix that allows you to make vertical loops

End Tangents Mode - Heuristic modes that allow you to minimize distortions around ends of spline.

Node Size - Sets the size of the nodes gizmos.

Show Node Links - Shows lines from one node to another, helps to understand the nodes order

Show Segments Path - Shows the actual spline curve, helps to understand how every separate segment will be bent.

Show Tangent Nodes,Show Tangents - Shows current bezier parameters for every node

Show “Save As” Dialog - When disabled doesn’t ask for the export folder during OBJ export, and uses selected default export folder

Show Export Result Dialog - When disabled doesn’t show “Export successful” dialog

Default Export Folder, Select button - Opens default export folder selection dialog

Extending Naming - Various naming options

Add node - Adds another node at the end of the spline.

Refresh - Forces the mesh generator to rebuild all the lofting groups immediately.

Spline Node

Additional Loft Angle - Additional pitch angle for current node. This angle is interpolated between adjacent nodes.

Tangent Guides Mode:

Auto - position of tangent nodes sets automatically considering value of Coefficient set in host Spline Former

Manual - position of tangent nodes can be set manually.

Split button - Splits the current node in two.

Waypoints Module

The Waypoints module of the SplineFormer component allows you to do a lot of things with the spline as if it was a path.

It has plenty of functions for working with the position relative to the spline.

Interface:

Enabled - Checkbox that enables/disables waypoints module

Number - Number of waypoints that will be generated along the spline

DrawPath - Enables/disables drawing of green arrow gizmos that represent waypoints order

Shift - Waypoints path shift relative to the spline axis.

Tips

✩ Do not change parameters unnecessarily.

It's not a skinned mesh, every time you refresh parameters it leads to full mesh regeneration.

Mesh regeneration is not terribly slow, but it's costly. I would not recommend regenerating it in every frame.

✩ When you change spline dynamically, disable unnecessary processing options. For example, welding and normals recalculation are costly operations, but not always necessary.

✩ Every vertex of the source mesh is bending independently, therefore if you want your result to look smoother, it doesn’t mean that you need to increase the number of the segments. You can just add more polygons to your source meshes.

✩ Note that the lofting path will go through the source mesh pivot. Therefore, if you want your caps to fit perfectly, your floor to be a floor, and there are no lofting artifacts, consider positions of the mesh pivots.

Considering the path as a thread and the source mesh as a bead, the pivot is a center of the hole in in the bead.

For example, collision mesh in road.FBX consists of three elements, their pivots are at the same position, so they snap together fine.

✩ Lower curvature coefficient leads to sharper edges. It’s useful for angular fences.

✩ Holding control+shift(⌘+shift) while moving nodes will snap them to the floor mesh/ terrain mesh.

Spline Power

Create stylish and detailed walls, racing tracks or level elements!

Spline Power

Mesh bending system

MVVM Dynamic

TextMesh Pro Effect

Damage Effect