Spline Refiner Manual


  1. Version Requirements / License / Installation
  2. Spline Refiner Overview
  3. Subdivision Tools
  4. Additional Tools
  5. Basic Shape Parameters
  6. Undo / Revert Actions
  7. Help/About section
  8. Contact/Support

Version Requirements

3dsMax 2012 and higher.
Spline Refiner has been tested succesfully on 3dsMax 2012 to 2020. It should also work properly on future versions. However, if you experience any issue, please report it to contact@splinedynamics.com


With every purchase you get a lifetime license. It’s a node-locked license.
The Regular License lets you use the product in 2 different workstations. It comes with 2 license keys (1 domain per key).
The Corporate License allows you to activate the plugin on up to 10 workstations. It comes with 2 license keys (5 domains per key).
You will get free upgrades for the same major version of the product.


  1. Unzip the content of the .zip file and then drag the “.mzp” file onto one of your viewports in 3ds Max . The plugin automatically installs itself.
  2. A dialog called “Software Activation” pops-up. Enter your license key in the text field. (You received a license key by email when you purchased the product).
  3. If the license key is correct, Spline Refiner will start.
  4. To add the plugin to a toolbar, go to the Menu > Customize > Customize user interface…
  5. Go to the “Toolbars” tab and pick the category “Spline Dynamics”.
  6. The plugin’s name (“Spline Refiner”) must be listed there. Just drag it onto a toolbar and you’re done!

Spline Refiner Overview

Spline Refiner is a 3dsMax productivity tool to fine-tune your spline shapes incredibly fast, in a simple and efficient way.

With this plugin, you can subdivide the splines uniformly, in a human-like manner, adding detail only where it needs to. So, you get a balanced segments distribution without altering the shape of your curves or touching the existing vertices.

Spline Refiner can process hundreds of splines in seconds, with just a few clicks! This tool will really speed-up your workflow and enhance your work!

Since this tool was ment to use at a final stage of the curves edition, it works better when provided with clean shapes, without overlapping vertices or other common issues that may cause undesired results.

Subdivision Tools

This area has 2 main tools: Equalize Subdivision and Increase Subdivision. Both have their own parameters.
The checkbox ‘Affect curves only‘ (at the bottom of the section) affects both tools.

Equalize Subdivision

This is the key tool of this plugin.
It subdivides every spline in the selected shapes as uniformly as posible, while keeping the exact original shape and vertices.

Average segment length (option buttons): choose between an automatic smart subdivision – considering the shortest segment as the average segmentation lenght-, or entering a custom value.
Action on multiple splines (option buttons): tells the plugin to consider a general segmentation length for all splines (absolute) or a specific one for each spline (relative).

The image above clearly shows how the parameters of Equalize Subdivision work. (‘Automatic’ refers to choosing the option ‘shortest seg.‘ as the average segment length.)

Increase Subdivision

This tool divides every segment of the splines in 2 halves, doubling the general segmentation.
The Iterations parameter sets how many times the function will be recursively applied.

Affect curves only (checkbox)
This is an important feature that affects all the functions in this area.
If active, the tools will subdivide only the curved parts and leave straight lines untouched. Very powerful feature.

Additional Tools

Optimize Straight Lines (button)
Removes all unnecessary vertices from straight lines. It’s a cleaning tool.
Threshold Angle (spinner): establish the maximum angle allowed between segments for removing vertices.

Make Linear Segments (button)
Convert all segments in selected shapes to linear and vertices to corner type.

Basic Shape Parameters

Interpolation (area)

In this section you can control the basic shape interpolation for all the selected shapes. They are the same parameters you can find in any shape.

Show vertex ticks (checkbox)
This option expose all the vertices of the selected shapes on screen. Very useful to see the changes in the segmentation while you apply the subdivision functions.


Undo / Revert Actions

These 2 buttons at the bottom of the UI help you revert the changes you recently made with Spline Refiner.
This is a custom undo system, since 3dsMax does not natively support undo for spline operations.

Undo (icon button): undo the very last action.

Revert Actions: reverts all the changes made with Spline Refiner on the selected shapes since you ran the plugin.

Help / About section

This section includes links to Spline Refiner Online Tutorials and to this manual.

The About area shows the credits for this plugin.

Contact / Support

For customer support or making suggestions or business proposals, please don’t hesitate to contact us through this Contact Form.

You can also write us directly to contact@splinedynamics.com.

All feedback is greatly appreciated. We will try to answer all your inquiries as soon as possible.


Enjoy Spline Refiner!