PolySurface Curvature by Jens Kafitz

  • Where to find it:

    • Add Procedural Layer / Geometry / Extension Pack /

    • NodeGraph / Right Mouse Click / Add Nodes / Geometry / Extension Pack /

From Mari 4.6 onwards this node will no longer be loaded. Use the standard Mari Node 'Curvature' instead

The Polysurface Curvature Node will detect your models curvature and output a mask

Optionally you can feed in a normal map via the Nodegraph to fine tune the result.


Due to MARI & OpenGL limitations Polysurface Curvature does not average the values between

individual faces.This can result in tesselated looking masks.

It is recommended to flatten the node and apply a Gaussian Blur to filter the mask.

Node Overview

Node Ports

  • Normal Map

Allows you to attach a tangent space normal map that should be used during the calculation.

This can be useful if you have a lowres mesh with baked normal maps from which you want to pick up curvature information

You can use the Mix Normal Map Slider to determine the strength of the Normal Map during the calculation.

  • Curvature

Overwrite the Curvature Slider of the Node with a Node Connection

  • Min Curvature

Overwrite the Min Curvature Variation Slider of the Node with a Node Connection

  • Intensity

Overwrite the Intensity Slider of the Node with a Node Connection

Node Properties



  • Curvature

Determines the threshold on the curvature. Curvature is evaluated as absolute values meaning there is no difference

between concave and convex curvature being made.

  • Min Curvature Variation

Determines the minimum normal difference between two vertex points need to have in order for the curvature to be 


  • Intensity

A multiplier on mask.

  • Invert

Inverts the result of the mask - black becomes white and white versa.

Normal Map (Nodegraph Only)

By utlizing the Nodegraph you can add an additional Normal Map into the calculation of the curvature.

To use this, attached a Normal Map Layer or Channel to the 'Normal Map' Connection in the Nodegraph.

  • Mix Normal Map

Determines the interpolation value between the objects normals and your normal map.

Extra Attributes

  • Hard Edged

Hard Edged Mode will clip any greyscale values giving you a 2-value mask - pure black & pure white.

  • Attenuate by Ambient Occlusion

Attenuate by Ambient Occlusion will multiply your Curvature and Intensity Sliders by Mari's Ambient Occlusion.

You will most likely have to adjust the Intensity to compensate.

Generate Ambient Occlusion

'Attenuate by Ambient Occlusion' relies on Maris pre-generated occlusion to work.

Generate Object Occlusion via the OBJECTS Menu first.