Wednesday, March 28, 2012

Bullet Integration - Small Goodies + Fixes

Just a quick update on this. As I finally managed to have some spare time today, I spent some time doing some "fun" hacking for a change (from writing reports and reading papers)...

Auto-Mass - Select a material preset to calculate mass
I've just pushed two changes to the Git branch:
1) An "auto-mass" feature, which calculates the mass of objects based on their volume sizes (mesh-objects just use the bounding box for now, which may overestimate in cases) and a "material" preset (which provides density information about the type of material that your rigidbodies are made from). Activate this tool from the "Change Mass..." tool in the toolbar, from the RigidBody panel. No more guessing mass values for hundreds of fragments by hand anymore!

2) An experimental patch from Sergej Reich which makes the collisions work properly out of the box (i.e. fixing the various problems with mesh-mesh collisions many were having).

These material presets currently include just a subset of things which I think will be useful for most Blender users. There's the ability to use a custom density by specifying the "custom" entry and then editing the density value afterwards, for fine tuning this yourself.

On reflection, these presets may even be nice to integrate as part of the physics settings instead. However, that is a matter for later, once people have had a chance to have a good play with this.


Now, the next target is getting some sort of caching/baking system in place...


  1. I guess if could be useful for materials as well, if it is extend it with other properties like IOR.

    caching...did I hear Alembic support? ;)

  2. Amazing work.

    I simply can't wait for what's next...

  3. hi
    i can't build with blender player, but i can without it, can you fix it please, thanks.

    here is the error i get:

    BTW, i use scons and msvcsp1 on windows 7 x64 and your latest push.

  4. that's really awesome! you can also see other technique and tips on this site I came accross this when i hit a wall doing some rendering stuff.

  5. Hi there very very nice.

    At the moment i stopped to work with the rigid body system because of limitation.

    The problem is when i try to use more then 2000 object it is not possible to use blender.
    I tryed to make a animated chainmail with round about 20000 rings. But now when i start the calculation
    (with record animation) the system stop to work after seconds because of big keyframe recording.

    Do you think with your change of the rigid body system including baking it would be possible ?

    Please see my last chainmail animation it looks good but it is only 2050 rings.

    Greets Andy