Real-Time Physics Simulation Forum

An update for anyone which might be having similar issues in the future. It turns out that the bug was in the export process for this specific asset. Because of the way the collision shape was generated, it would happen to be rotated 90 degrees. This obviously produced different results and since my...

After quite some grief, I've isolated the data involved in the previous tests to a minimal example. Here is some output. --Redacted-- See update note. So far, it was my understanding btManifoldPoint was basically a "touch" vector from point A to point B, with distance being positive (A-->B...

There's no API to do this but the SDK contains a few examples.

• Your first choice is to look at maya to produce a .bullet file and load it up. See Bullet/Demos/SerializeDemo.
• OBJ parsing, see Bullet/Demos/ConvexDecompositionDemo. That's a bit crude in my opinion but it works.

I am still using 2.78. In my game, I have an object which spawns other entities. Those spawned entities are kinematic actors. Because I don't want to decouple their graphics from their physics too much and I don't want them to just pop out. I've set up my "spawner" mesh to provide a "...

If the "top" is everything above the center of mass, manifolds can give out points on both objects, in world space. So, if we have our point and the centre of mass (which you can get with relative ease) then we can figure out if an object is "on top" of another by dotting the dis...

You don't. Attach it to a physics object such as player's avatar.
Modelling your camera as a physic object has plenty of opportunities to bug, I even read about a game in which it somehow ended having health and thus being killed by area attacks. Just don't.

I am investigating a similar problem right now. My current speculation is the ground they slide on might have small imperfections, thus causing them to hang on those. I'll hopefully be able to fix this in a couple of days, maybe the solution will give you some ideas. Do you have this issue when on g...

Where can I find information about memory management, and keeping references for bullet? The rule is simple: if you new something, you must delete it. Everything that is allocated in bullet is freed by bullet. In other terms, you own resources you allocate. That's it. It's in the manual. I noticed ...

I'm stuck there and can't find docs explaining how to actually display it on the screen. You don't really. Ok, we want to display it for debugging purposes I guess. You can find what you need in pretty much every bullet SDK demo. Everything revolves around implementing btIDebugDraw. You then pass t...

Sorry, I have no real data for this case.
I'm replying so I get notifications as I'm interested as well.

I mean, what model format . Obj, collada, ASE, md3... Problem is, the model must either be rigid or be built by as an assembly of rigid bodies. Models, especially when kinematic, are often very simplified. Sometimes, the collision geometry does not look like the graphical model (see fig. 23-9 ). My ...

Without seeing the model it's hard to tell whatever a convex hull will be sufficient. I'm fairly sure there's an obj->bullet serialization example in the 2.78 SDK (and probably in all others). It produces a polysoup so you're strongly encouraged in using a lower-detail LOD for the model. Of course t...

Read the manual. You can pull out this exact variable by calling btCollisionWorld::getCollisionObjectArray().

We are wondering if this is a know bug? Or maybe we don't use the correct way to deserialize the buffer we got from the serialization? Why didn't you choose a symetric way of saving / loading data? I also wonder why. The serialization looks symmetric to me, it's just incomplete. For example, in 2.7...

There are a few code snippets ready to go in the Bullet SDK. Personally I believe they're a bit crude but sure they're much better than nothing.
There's a demo regarding loading a BSP world and a world is technically a model... what model are you looking for in particular?