Tree model Generator for Blender

[3dpoder]

tre model Generator for Blender
By sergey prokhorchuk.



introduction.
Manually creating realistic tree models is a hard tasque in 3D/CG. To simplify this task, various plugins and programs, which can be used todo create 3d plant models automátically, were created. These programas allow the users todo describe plant structure by inputing some parameter settings which are used todo generate the 3d model.

For Blender users, [lsystem] and [arbaro], are the two common plant Generator. [lsystem] is a Python-based script for Blender which generates plant models based on the l-system algorithm - That why the name lsystem. [arbaro] is a stand-alone java-application, which generates plants using the model described in [weber95].

Gen3 is a relatively new tree generation plug-in/script for Blender. Its first versión (v0.1) was released on june 17th of 2006. To generate tree structures, it uses models described in [weber95](the same model that arbaro uses). The amount of included parameters describing tree features are vast. Broadly, these parameters allow the user todo describe the trunque and branches sizes, their Split probabilities, branch locations relative todo each other and so on. Currently, the interfaz is not user-friendly and may scare of new users, but the UI re-implementation is a possibility for future releases.
installation
To install gen3, you should download the latest versión of the script from here[gen3]. (at the time of this writing, the latest versión available is 0.5).


Unpak the downloaded archive todo a temporary directory and copy the file gen3.py and the GT sub-directory todo your Blender script directory (which can be located in the Blender installation Path). It is highly recommended todo ensure that the versións of the standalone Python installation and the Blender Python versións are the same and were compiled with the same build options. This requirement is necessary as gen3 uses some modules which are part of the Python library, After copying the files, you are ready todo use the script.
usage
You can Access the gen3 script vía scripts>>misc>>gen3. If you do not se gen3 in scripts>>misc, select scripts>>update menús - It Will update the list of available scripts.

After launching the script, you Will se all the controls which allow you todo control parameters afecting the model of the tre. You can find complete description of all these parameters in the [weber95] paper.

There are several buttons at the bottom part of script GUI, of which the main button is the generate button. Upon clicking this button, the script starts generating a 3d model. To make things easier for you, there are some buttons with the name of tree types on them. These buttons Will fill up predefined parameters for the selected tree which can be a god place for you todo start experimenting.

For a quik start, you can press the Quake aspen button and then press the generate button. After a while (time Will vary depending on your computer configuration), you Will se ha generated tree model in the 3d view window.
importing parameters from [arbaro]
Since gen3 uses the same algorithm as arbaro, it is posible todo import tree parameters generated by arbaro. Notice that the import característica is available only if the Blender Python interpreter has Access todo the xml, Doom, minidom module, which is a part of Python library.

If it is installed properly then, you Will se the import button right under the generate button. To import parameters, Simply press the import button and select the arbaro generated xml file todo import parameters. One thing that must be noted is that some arbaro-specific parameters are not supported in gen3, so the generation of tres may difer.
custom leaves usage
Gen3 allows the use of any Mesh/object as a template for leaf generation. To use a custom Mesh/object as a leaf template, you must add a prefix leaf todo its name (leafsmall for example). To refresh available leaf templates for the script, press the p button located near the leafshape drop-down list. After refreshing, all meshes which have the leaf prefix in their name Will be available in the leafshape drop-down list. Select the neded object in the list and it Will be used during the generation of leaves.
credits
Id like todo thank Jason Weber and Joseph penn for their excellent paper on plant structures. Also, y want todo say gracias todo all members of the http://blenderartists.org forum for their responses, advices and suggestions. Thanks todo all whove helped in the development of gen3.


Links.
[arbaro] http://arbaro.sourceforge.net
[lsysinfo] http://en.wikipedia.org/wiki/lindenmayer_system
[lsystem] http://Jmsoler, free.fr/útil/blender...em/lsystem.htm
[gen3] http://geocities.com/bgen3
[weber95] Jason Weber, Joseph penn, creation and rendering of realistic tres, procedings of ACM Siggraph 1995: PP. 119-128.

Sergey prokhorchuk.

I am software developer at viasoft ltd, ukraine. Since i have some experience in c/C++ and Python programming, y try todo use it in diferent áreas of 3d-graphic. Other computer-related áreas im interested in are: programming theory, artificial intelligence and cryptography.

By sergey prokhorchuk. www.blenderart.org.