---
title: "Align to Spline Expression"
url: "https://help.maxon.net/c4d/en-us/Content/html/TALIGNTOSPLINE.html"
section_path: "Object Manager > Tags Menu > Animation Tags > Align to Spline Expression"
element_id: "TALIGNTOSPLINE"
command_id: "5699"
description: "This page describes the Align to Spline expression tag in Cinema 4D, one of the most frequently used animation helpers. Instead of keyframing positions …"
---

# Align to Spline Expression

> **Note:** **What is it about?**
>
> This page describes the **Align to Spline** expression tag in **Cinema 4D**, one of the most frequently used animation helpers. Instead of keyframing positions, you animate a single percentage value to move an object along a spline — ideal for camera rides, roller coasters or objects following complex paths.

This is one of the most frequently used expressions that allows you to place objects on splines and follow the spline progression (animation of position). This often makes it easier to create animation paths than with a pure object position animation.

# Example

In the following example, the Align to Spline expression makes the airplane follow the black path spline. An additional Rail spline (red) ensures that:

1. the airplane turns into the curve.
2. a gimbal lock effect is prevented during looping.

[Video: 2026](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2026-1_align_to_spline_tag_01_.mp4)

[![Image: halvar.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/halvar.png)](https://help.maxon.net/c4d/en-us/Content/Resources/Scenes/2026-1_align_to_spline_tag_01_.c4d)

# Cooperation with deformers

One disadvantage of expressions, however, is that they cannot use splines that have been deformed by a deformer, but only the undeformed original state.

There are several tricks to make this work anyway (download a file below that uses the different methods):

1. Use a [MoSpline](https://help.maxon.net/c4d/en-us/Content/html/OMOSPLINE.html.md) in *Spline* **Mode** and use the deformed spline as the **Source Spline**. The MoSpline itself then takes on the shape of the deformed spline. The MoSpline is then defined as the source spline in the expression.
2. The command **Current State to Object** can be used to convert the deformed spline into a 'standard' spline.
3. The use of a cloner is somewhat out of the ordinary, as no align-to-spline expression is used here, but the object is simply cloned on the spline and follows the spline course using an **Offset**.

[Video: 2026-0_align_to_spline_01_.mp4](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2026-0_align_to_spline_01_.mp4)

[![Image: halvar.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/halvar.png)](https://help.maxon.net/c4d/en-us/Content/Resources/Scenes/2026-0_align_to_spline_01_.c4d)