Real-Time Physics Simulation Forum

When multiple static objects which are added using the add object actuator only the newest one has a collision mesh. Dynamic objects added this way behave correctly.

In addition, all the actuators which are in the last created static mesh are also applied to every other copy of that object even if only one of them is triggered. For example if end object actuator is triggered in one object, then all the objects vanish.

These bugs are present in Blender 2.43, but not in 2.42a.

Also .setNumTimeSubSteps() doesn't work in Blender 2.43 as it worked in 2.42a. This was handy for pausing the physics.

Here's .blend showing the bug:
http://users.tkk.fi/~pkangass/addobject ... _bug.blend

Does any one have any solution suggestions for this issue, or can point me to an official place where this glitch can be reported? I've been using the game engine to auto generate arbitrary size mazes from a finite set of wall block objects and have only just discovered this loss of collision mesh bug when I started testing a player character walking through the construction

I've noticed with the new "show physics visualisation" game option that collision meshes initially show up in white, then after a 2 sec (120 frames) they switch over to green. Interestingly, if a mesh has gone 'green' it stays around and is not wiped when a duplicate is added. Only the meshes still shown in 'white' are lost as a duplicate is added. So, if I add my mesh objects only once every 2sec the collision mesh does seem to survive the duplicates - but that's not a very practical option

Any one have an idea what the physics visualisation colours actually mean - I can't find documentation about it

Final observation: if I switch back to the depreciated sumo physics system all works correctly again, with no loss of collision meshes. So it does seem to be bullet specific.

Many thanks,
Gary

Add object collision bug is fixed in this new build: http://www.continuousphysics.com/ftp/pu ... 4post2.zip

psk wrote:Add object collision bug is fixed in this new build: http://www.continuousphysics.com/ftp/pu ... 4post2.zip

Fab, thanks - that's great to know there's been a resolution. I can't test this build to confirm the fix unfortunately as I'm OS X only (PPC). I'll keep my eyes open for the next official release. I'm guessing the 2.45 release stepping stone has stalled due to SIGGRAPH activity, fingers crossed that this Bullet patch made it in.

Anyway, happy to switch over to other tasks for a while knowing I can come back to the physics set-up later.

Thanks for you help,
Gary

Yep, just wanted to confirm with folks that add object actuator + duplicate objects causing the loss of collision meshs bug in bullet seems fixed My random maze level generator is now a testable walkthrough with a player object using physics

I finally managed to find http://www.blender.org/news/article/ble ... candidate/ and test the RC build on my set-up (it was version 244.1). This specific issue also gets a mention in the bugfix list:

The Bullet Library (for Collision Detection and Rigid Body Dynamics) has been upgraded to 2.53. This fixes a series of bug regarding 32-bit precision, collision detection, friction calculation, kinematic objects and several memory leaks.

Thanks to whoever got this report in and to whoever made the patch!

I've found a new bug that concerns added objects: they always go to sleep mode even if "No sleeping" is set. Sample: http://users.tkk.fi/~pkangass/blender/a ... _bug.blend

Ghost and rigid body buttons also have no effect on added objects.