Is the source code for your Newton / Bullet / PhysX tests available anywhere? I've got people on my forum who insist "PhysX is the best because Nvidia" even when I am showing them proof:
http://www.leadwerks.com/werkspace/topi ... wton-sails
Moderators: Sascha Willems, walaber
Julio Jerez wrote:there is a Unity Newton Plugin that the can use to compare Newton and PhysX side by side.
From: John Ratcliff [mailto:jratcliffscarab@gmail.com]
Sent: Thursday, June 06, 2013 10:48 PM
To: Julio Jerez; Jerez, Julio
Subject: Re: PEEL tests
Tomorrow I will add the Bullet peel plugin to the depot so we can add it to the data set.
On Jun 7, 2013 12:34 AM, "John Ratcliff" <jratcliffscarab@gmail.com> wrote:
Julio,
I'm about to head to bed now; but I've been going through some of the tests; which I assume you have done as well.
Here are some things I have noticed
#1 : Newton seems to be a lot more efficient with compound shapes than PhysX. This is especially noticeable in test #59 and #60
#2 : Newton handles interpenetration much better than PhysX.
#3 : Newton seems to have a much more aggressive sleep algorithm than PhysX; as can be seen in large box stack tests where PhysX falls over but Newton puts them to sleep fairly quickly. This isn't necessarily a good or bad thing; it's usually just a tuning parameter.
#4 : All of the demos involving constraints where there are long chains or, especially the 'nets', the behavior of Newton looks *much* better. The performance is lower, but that's almost for sure simply because the solver-iteration count on the PhysX constraint is too low. I'm sure if we increased the solver-iteration count on the PhysX constraint to make the behavior match more closely to the quality of the behavior in Newton the performance would be much more close.
#5 : The ragdoll demo looks better in PhysX than in Newton. This may be just because you haven't fully hooked up all of the constraint properties yet? The PhysX constraints have a lot of spring/softness to them that tend to make ragdolls look a little nicer.
#6 : In general Newton seems to be very performance competitive with PhysX until you start hitting extreme situations of massive numbers of dynamic objects all in a giant pile. I'm going to assume this is what you meant by an artificial demo. I agree this isn't necessarily that big of a deal.
As we discussed earlier, you have to be careful about drawing too many conclusions too quickly, since many differences could be due to iteration counts or other kinds of tuning parameters.
These are just some things that I have observed so far.
You are putting a lot of work into getting Newton to work with PEEL; I think we should discuss a plan to present the data when we are finished. Perhaps something on either your website or my blog. Something which is diplomatic and complimentary.
In my personal view, Newton is a very impressive high quality physics engine with excellent behavior and performance. The fact that it is even competitive with commercial physics engines that have had dozens of engineers working on them for years is really an incredible testament to your talent and dedication.
I think you have done an amazing job, and we should communicate that to the public as well.
Great work.
John
The proof isn't right infront of my eyes, his test (which is bias just like every other test that claims one physics engine trumps the rest) shows that for his implementation of each physics engine to do the same thing, he produced the best results with Newton. Who's to say I wouldn't be capable of doing that with any other physics engine?
I've got to say I never thought Newton was THAT good of a physics engine, very underrated i must admit. You do tend to pay in most demos in performance for Newtons accuracy though.
they decided not to use my integration and went with their own bogus newton version.
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