Blender is a open source 3D content creation program. While it's usually not at all well-suited for engineering, scientific, and other CAD purposes, it's a popular content editor that is really good at some forms of editing (surface editing in particular).
This task has you write a tutorial on how to model something in BRL-CAD, render the geometry, export it to a file, import that file into Blender, and render the imported geometry. Make a region of two or more primitive objects for export -- a single primitive is insufficient. Include lots of screenshots for every step along the way.
References:
- http://brlcad.org/wiki/Documentation (particularly the MGED tutorial and quick start)
Tools:
- blender
- g-* (we have lots of exporters, use any that blender supports)
- mged (display and edit geometry, run "tops" and "draw" commands)
- within mged: rt -s1024 -A0.75 -c {set ambSamples=128} -c {set ambSlow=1}
Note that exporting geometry from our CSG format to a polygonal format can be VERY difficult. It's a black art. If you encounter an export failure/bomb/error, you'll need to edit the geometry you're attempting to export, try different tolerances, change your hierarchy, or try a different geometry exporter.
| File name/URL | File size | Date submitted | |
|---|---|---|---|
| BRL-CAD to Blender.docx | 41.8 KB | December 14 2012 21:07 UTC | |
| BRL-CAD to Blender.docx | 223.8 KB | December 15 2012 12:30 UTC |
I would like to work on this task.
This task has been assigned to John. You have 72 hours to complete this task, good luck!
Daniel,
do you know any good .g files for me to work with it?
There should be some example databases. Open them with mged (for example) and select one for your tutorial.
Daniel,
Where should I post my tutorial?
Do I realy need to actually model something on BRL-CAD? Can't I simply use an existing file?
You'll post your tutorial here for starters and once it's looking good, you can migrate it to our wiki.
You can use one of our example databases (there are dozens included in an install), but know that some of them will not export to Blender. Look for the moss.g model, that should be a nice and simple one that you can demo.
The work on this task is ready to be reviewed.
My computer is very very very very very very slow and taking images is taking me way to much time.
The only problem is that without the images, the tutorial isn't useful. The reader has no way of knowing whether what they've done is right or wrong. It needs to show a picture of the model in MGED and a picture of the final resulting model in Blender.
As for the text, there are a few mistakes to correct:
And again, it needs at least two more images. It needs an image of moss.g's all.g in mged (run "draw all.g" then "ae 35 25" then "zoom 1.5" then Tools-Raytrace control panel). In needs a full-screen screenshot of what results immediately after importing the dxf.
One of the mentors has sent this task back for more work. Talk to the mentor(s) assigned to this task to satisfy the requirements needed to complete this task, submit your work again and mark the task as complete once you re-submit your work.
The work on this task is ready to be reviewed.
Melange has detected that the deadline has passed and no more work can be submitted. The submitted work should be reviewed.
Congratulations, this task has been completed successfully.
Now that's MUCH better. I even like how you extended the tutorial to talk about how to reparameterize the triangle mesh into a quad mesh once imported into Blender.
Note that the reason for the scaling size disparity is because the moss.g model is modeled in millimeters and Blender was apparently set to meters prior to import. If set to mm, the scaling step shouldn't be necessary. Unfortunately, the dxf file format doesn't encode units, so the user must either make sure export units match blender or import units match brl-cad.
Thanks again, nicely done!
As GCI comes to a close, we wanted to take the time to say THANK YOU for all your efforts. This comment interface closes after GCI is over, so you're encouraged to join our mailing list where we'll be announcing contributions from GCI participants like yourelf over the upcoming months:
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