UCT CS Research Document Archive

Automatic Creation of Physics Components for Procedurally Generated Trees

Crumley, Zacharia (2009) Automatic Creation of Physics Components for Procedurally Generated Trees. Technical Report CS09-04-00, Department of Computer Science, University of Cape Town.

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The field of procedural generation is becoming increasingly widespread as a tool for generating content in video games and virtual environments. Procedural generation creates content (such as 3D models) automatically, saving large amounts of time and money, as no human interaction is required. One area where procedural generation excels is the creation of trees, which is most commonly achieved using L-systems.
The problem with these generated trees is that they are static and do not have any associated animations or dynamic behaviour. Our research addresses this problem by presenting a technique for adding physics components to trees created by L-systems, so that they can be simulated using a real-time physics engine, making them react dynamically, and realistically, to their environment. The algorithm works by creating a physics skeleton for the tree that can be used to approximate real tree behaviour.
In order to improve the computational performance of our system, we also present some level-of-detail schemes aimed at real-time physics simulations. These schemes are not suitable for all cases, especially those which require a high level of realism, but can improve performance.
We test both the computational performance of our system, including it's ability to operate in real-time, as well as the realism shown in the dynamics of the produced trees. The results indicate that our trees are very realistic and an improvement over those found in modern video games. However they also show that our system is not suitable for real-time use as it stands. We believe that research into further optimizations and culling techniques could change this, and recommend a number of avenues for future research in this regard.

EPrint Type:Departmental Technical Report
Keywords:Procedural Generation, L-Systems, Physics
Subjects:I Computing Methodologies: I.3 COMPUTER GRAPHICS
ID Code:590
Deposited By:Crumley, Zacharia
Deposited On:21 January 2010