Hello everybody,

I've been working on my 3d verlet engine, and I thought I should share some insight about this before I upload the new version. First of all, if you haven't noticed, the previous versions of the engine would occasionally "BLOW UP" for no apparent reason.

Well, that is what is being addressed in the current version. Things that I have found out in the process are:


1) don't assume the problem is the friction calculation (see below)
2) if the intersection code is faulty, all bets are off, therefore friction calculation can fail as the result
3) most of the errors are caused when velocity vanishes, this means there is no tangent vector!
4) when all else fails, just abort the operation... the next interation will handle it

Your thoughts?

Your thoughts?

My thoughts? My thoughts are I'm not sure how to respond to this thread. Are you asking for specific feedback about a specific problem/question/potential solution?

[quote name='bpj1138' timestamp='1348299648' post='4982600']
Your thoughts?

My thoughts? My thoughts are I'm not sure how to respond to this thread. Are you asking for specific feedback about a specific problem/question/potential solution?
[/quote]

I'm asking for other people's experiences solving the contact force problem. It seems to me when objects come to rest, which is obviously the solution, velocity goes to zero, therefore, you have to "catch" that condition in the code, which is obviously an invalid condition... velocity is zero, therefore time is zero, or objects are "at rest"...

When such an error occurs, he X-Purge engine will print out an error message, like "tangent not unit"... which means, relative collision velocity was zero, therefore there was no tangent vector. It's always at the extremes where the system fails.

Unfortunately, I just tested the engine again and found it still "BLOWS UP". Stay tuned...