GeorgeH wrote:
Gimli,
I personally don't use custom balls that much any more so fake ball spin doesn't really do much for me because I can't see the ball spin anyway. ...But it is pretty cool the way you made it work though.
George
This is what made me delete my thread on this. I tend to use a Standard Silver ball most of the time and don't notice the lack of spin at times...but it is glaringly obvious on textured balls, which I do think are amazing and definitely have their role.
monnezzas wrote:
This is a nice experiment and for sure it will be useful to create some special fx in a table.
Thinking about using this for the ball physic is too complicated for everyone (even if automated) and not the real problem.
It is not complicated at all just a ball toy placed at a predetermined spot and a code segment that is simply copy and pasted. And this does not effect the physics, it just corrects a visual artifact of a non-rolling ball
monnezzas wrote:
Let's say one important thing:
A skidding ball....
OK that's was only an example, but this shows why I don't think that is a visual problem, we should not cover the problem cause the problem remains under that cover.
You may be onto something....
Temporarily counterbalanced spin through"Skidding" or "Sliding" vs
Exceeding the Pinball Simulation Limits (Artifact)
1.
Artifact Theory - The ball should be visually spinning but isn't.
Why ? There are so many parameters in Newton Physics Engine to simulate objects in motion. And it is only a narrow band that is applicable to a ball, let alone a pinball that we expect to behave in certain way.
When the physics strays beyond the boundaries of our pinball expectations, then other things occur. And in our case the spherical ball starts behaving like a "cube" according to Monnezzas (but I believe he is observing "Skidding' see below) or a "hockey puck" which is my perception and supported by understanding "damping"
Angular Dampingthere are two types of damping Linear and Angular according to this site:
https://docs.unrealengine.com/en-us/Eng ... AndDampingLinear damping is like putting on the breaks to linear movement
Angular Damping slows or stops rotation (spin)
The Damping in physics tweaks /the FP xml is Angular DampingMy observation is that if you increase Angular Damping to 10. The ball behaves like a puck
(no longer a Pinball) and is very predictable as all spin has been removed.
Removing angular damping gives a crazy rotation and ball behaves like a ping pong ball.
(No longer a Pinball)
2. Temporarily Counterbalanced Spin ("Skid" /"Slide")It may be possible that what Monnezzas is seeing when he describes weird behavior to non spinning ball are during times of Skid or Slide.
Skid - Is like a car putting on the brakes....picture a ball rolling up the table ...it should have a rolling rotation at a certain speed.
If this is perfectly offset by backspin then the ball will skid up the table and you will see no rotation....until these offsetting factors no longer match (ie back spin force dissipates,
or a different surface with different friction like a ramp is hit)
The visual appearance of no rotation in a Skidding ball....must be a rare occurrence
because it involves perfect offsetting of all axes of rotation..which would be next to impossible in a ball spinning along multiple axes at the same time.
Monnezzas has observed this in plunger lanes and slingshot lanes...so I suppose that is possible as the ball is being constrained by the lane guide wires and rubbers
Slide - Is like a car hitting a patch of oil on the road. Occurs when the frictional force suddenly lessens.
Again this can lead to a non-spinning situation if a previously stopped ball fails to rotate as it falls if no rotational forces have been applied and no frictional force are resisting.
A non-spinning sliding ball probably will behave more predictably than a skidding ball as it has no rotational forces. The skidding ball still contains all of its desire to spin and when
hit it will unleash these unseen dynamics as its forces are no longer being concealed by offsetting forces.
Conclusion:
There a two glaring problems that FP has been charge with:
1. Poor Flipper Aiming - thanks to Rav's dynamic flipper coding we can now dramatically improve this.
2. Wildly unpredictable ball collisions. We can dramatically improve this by increasing angular damping.
Problems:
We can end up with a too predicable table that always responds how we predict and therefore doesn't seem real.
This is fabulous problem to have ! From there all we need to do is slightly loosen our parameters or include a tiny measure of randomness in the code.
If constraining angular rotation leads to the artifact described above, we can deal with that
as described previously.
The true significance of "Skidding" as a real problem remains to be seen