Eurographics Computer Animation and Simulation EGCAS'96
Proceedings published as a book by Springer-Verlag Wien in the
Eurographics Series.
To order contact
Eurographics (for Eurographics members) or
Springer-Verlag
Interactive Modelling and Animation
of Branching Botanical Structures
Bernd Lintermann and Oliver Deussen
Department of Computer Science, University of Karlsruhe
Contact
Bernd Lintermann
and Oliver Deussen
-
Abstract
We present a method for interactive modelling and animation of natural
branching structures such as plants. Objects are created according to
a rule based description. Geometric information is encapsulated in the
objects and can be edited by methods such as free form deformation and
spline techniques. Global and partial constraints allow the modelling of
specific plants. The rule system is represented by a structure tree
with components of high functionality that can be edited graphically.
Keyframe techniques are applicable and allow to simulate parts of the
models with local time. In comparison to other rule based approaches,
complex branching structures can be developed faster and more flexible.
Animation(s)
These animation were created on a Silicon Graphics Maximum Impact with
R4400/250MHz processor. The animation sequences are designed interactively
and then rendered using an internal shader. Local times and iteration
numbers of parts of the models like twigs and leaves are passed to the shader
which modifies textures and colors according to that information.
Fern (489kB) MPEG Movie
The keyframe sequences for a leaf is designed once and embedded into
the keyframe sequence of a twig. Each time a twig generates a new leaf,
a local time is assigned to the leaf and it grows according to that local time.
A component arranges twigs according to the
golden section. The animation of new twigs works the same as for the leaves.
225 frames rendered in 10 hours with 720x568 pixel on an Indigo Extreme R4400/135MHz.
Ivy (460kB) MPEG Movie
This animation illustrates the use of global constraints. A field, defined
via a special component, forces the ivy to grow around the stick. The
appearance and developement of leaves is controled via embedded keyframing as
described above.
300 frames rendered in 5 hours with 720x568 pixel on a Maximum Impact R4400/250MHz.
Tree (679kB) MPEG Movie
This sequence is created for Bill Viola, an american video artist.
It shows the whole life cycle of a tree compressed in one year. Blossoms and leaves are animated with
embedded keyframing. They die at defined synchronization points in time. Local time
and iteration numbers are used to modify the color of leaves over time individually.
224 frames rendered in 36 hours with 568x720 pixel on a Maximum Impact R4400/250MHz.
At middle of august the software will be available as shareware.
Try www.greenworks.de.
mail to linter@zkm.de
and deussen@deussen@inf.uni-konstanz.de
Last modified: Wed Jul 17 16:22:09 MDT 1996