Saturday, June 22nd, 2019 Posted by Jim Thacker

Digital Expressions Sweden releases Tropism 1.0 for Modo


Digital Expressions Sweden – aka developer Fredrik Widman – has released Tropism, his long-awaited procedural tree-generation plugin for Modo.

The software enables users of Foundry’s 3D software to grow generate branching structures like trees, other plants, networks of veins – and even lighting strikes – using standard Modo controls to influence their forms.

(Full disclosure: Tropism actually shipped earlier this month, but we only spotted that it was out when Pixel Fondue covered it in a livestream previewing Modo 13.1.)

Generate and animate ultra-customisable trees and plants using standard Modo controls
Originally previewed in 2017, Tropism implements the tree-generation methodology set out in 2007 paper Modelling Trees with a Space Colonization Algorithm inside Modo using a system of custom Mesh Ops.

Users can choose where a tree grows by using a locator to set the position of its roots; or generate a branching network inside an existing volume or particle system, or along existing surfaces or curves.

It’s even possible to paint particles onto a surface and have Tropism generate vines in real time.

Users can control or animate the growth of a Tropism object using custom parameters like gravity and age; via guide curves; or by using standard Modo controls like deformers and effectors.

Once a branching network has been established, separate operators generate twigs and leaves, the latter created using custom billboards and instanced using Modo Replicators.

Geometry can be exported as either polygons or Catmull-Clark subdivision surfaces, with the option to adjust geometry count. Tropism automatically generates UV maps.

Widman says that for future releases, he is investigating a phototropism system, in which the lights in a Modo scene influence the growth of a plant, and support for wind animation.

Pricing and system requirements
Tropism 1.0 is available for Modo 13 running on 64-bit Windows 7+ or macOS 10.13+. It costs €50 (around $57). The software comes with a set of example scenes and detailed video training.


Read a full list of features in Tropism 1.0 in the product’s online store

Read more about Tropism in the discussion thread on Foundry’s forum