Bump. I did work out the right calculation for this some time ago - it is Ixyz=Icm+md^2 where Ixyz=Inertia along any axis of an altered centre of gravity, Icm= Inertia of a centroid - basically symmetrical centre of gravity - this is the result from the calculation mentioned earlier(i=(m(a^2+a^2))/12), m=mass and d=distance from centroid, I was just holding off making unnecessary posts as this is still not solved, the 2 calculations where only part of it and there's nothing worse than making post after post in a short period of time with nothing of value to show for it. I was able to work backwards obviously by using the target results with that calculation and determined the centres of gravity. Looking at it on 2 models(cucumbers bmw and the fiero example) the centre of gravity is located roughly forward and up near front of dashboard in both cases - the real centres of gravity for vehicles in real life are definitely not situated where I found them!

So if I have worked it out then why is it not as simple as this? Because Walaber put in some calculation to get the centre of gravity prior to making the calculations, well at least not get it but produce it where he felt the results of the inertia affected the vehicle best. What I seem to recall is that I think he mentioned something along the lines of it needed to be relatively close to the actual centre of gravity. He is also definitely only using the objects data to influence this formula's output.

On top of this issue he is somehow either getting a negative result in certain situations purposefully or it's an error - because you may notice in either calculation there is the power of 2 used - which will never yield any negative number. This is shown in the results of the 1*1*1 cube above. I think it is purposeful on the basis that it would be impossible to get a negative number from those inertia calculations - which reinforces my thoughts that not just internal commands where used. Then again I suppose it could be undesirable results rather than an error, but based on what I mentioned early on I doubt it(that uniform objects have two results less than the third - and the third result is correct(z axis)). It would have to be a negative value to yield the results of the cube because the altered centre of gravity calculation involves adding the centroid results to the second part of the calculation. I can't even check slightly less uniform object results because since M1U plugin had some dll's just stop working on my rig, the RBD tool has also stopped working...this is the very reason I started this project lol. At least now I know that it was a change in my systems software somewhere along the lines that caused it. What I don't get is why Walabers tool stopped working(written in dbp) even though my own exes prior to the m1u compile issues still work!

One interesting thing I have noticed just now - in the actual vehicle demo 6 - even though inertia results for altered centre of gravity are used, at no point did anybody use the actual command to finalise the new centre of gravity!!! Could be purposeful, might not be though as I spotted a mistake in the code for velocity - where vector axis' xxx are used instead of xyz and if there's one mistake, well enough said. One thing I forgot to mention at the beginning of all this - the cars body(of which the sizes are used to make the calculation) is non centroid as its pivot point is at the base of the model not the centre. I think the reason we treat it as centroid is because the vehicle is an invisible box so the cars body bounds are actually only the top half of the entire vehicles mass. When I render a transparent object of same dimensions as body frame with object bounds showing and orientated/situated to match the vehicle, the behaviour of the vehicle makes more sense. This does mean that mass should be doubled really as should the y dimension...something I should look into soonish. I also seem to recall someone saying they had to double the mass to get things to work better - pretty sure this was kjelle as I also recall them saying that both themself and Walaber had to almost double the mass(kjelle worked on the wrapper after Walaber which is why I think it was kjelle who said it). The real question there is why they didn't double the height of the vehicle body frame in the inertia calculation - otherwise the calculation seems, well, wrong.

**So what would help me now is suggestions** on a way to guesstimate this centre of gravity which is nowhere near a real centre of gravity in real life, along with any suggestions on why uniform objects have a negative result in x and y axis even though ^2 is used! I can leave it to the end user to place the centre of gravity themselves, but I would rather they had 3 choices than 2 especially as I may be entirely wrong and the Walaber calculation might be 100% correct for all I know (3 choices being, centroid mass, their own manual positioning of a new centre of gravity and the 3rd being Walabers automated version).

Edit: Forgot to mention that the dimensions of Walabers offset in the z axis does not change but the x and y - are actually the same offset values for fiero and either the same or very close to one another for the bmw(probably the same - I can't quite recall, if anyone feels that this bit is important I will double check, just ask).

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