## Questions regarding Collisions, IK, and movement

A place to discuss everything related to Newton Dynamics.

Moderators: Sascha Willems, walaber

### Questions regarding Collisions, IK, and movement

Hey,

Still have to migrate to Newton 2 (with Delphi, I saw Sascha has fresh units ) for my hobby game Tower22. Anyway, I like to know a couple of things before going on, so I need some expert advise. Maybe these questions are too much to quickly handle in this topic, so if you really like to help you could also mail me on [nieuwlaat dot r @ gmail dot com]. Would be very appreciated!

Ok, here it goes:

1.- Collision test
Newton can check collisions for sure, but how about knowing if a collider is inside a special (non colliding) volume, such as a water block? I'd like to add special volumes to my (static) world model so I can see if my player is inside water, nearby a ladder, on a conveyor belt, anti-gravity zone, hazardous volumes etcetera. I assume it's possible to detect
collisions with special polygons, then ignore them. But how to detect if a collider is INSIDE (thus not intersecting) a volume?

2.- Ragdolls versus elipsoid
Currently I'm using an elipsoid as character controller. By giving it force it will move around, and the visual player model will follow it. However, I have a few cases where I want ragdoll collision detection instead. First, when the character dies I want ragdoll physics. Can I just simply replace the elipsoid with a ragdoll collider (but how about using the current force applied on elipsoid on that ragdoll)?

Second, for bullet collision detection, I also want to use the ragdoll (bullets use raycasting) to have a more accurate detection. That would mean I'll have to maintain a ragdoll and the elipsoid at the same time. Not sure what is the best thing to do though...

3.- IK & Animations
Does Newton have any functions or demo's that do (simple) IK on a skeleton? I'd like to properly walk the stairs and such.

I might also need somewhat more advanced usage of IK. I have a big snake like character in mind that can move towards towards the player. So, I need some sort of IK to get the skeleton in motion, AND to update the collider positions for proper collision deteection.

Simply pushing an elipsoid comes with a couple of issues:
* Synchronizing animation (you may move faster/slower than your legs walk)
* Complex moves (climbing a ladder, hanging on a rope, etc.) may need special physics, or none at all.
I was thinking about using the Skeleton Animations to generate the desired motion. However, animations are not aware of collisions/gravity of course. How to combine animations, physics (and eventually IK)?

Newton2 has some updated Character Controller from what I know, but I have no idea how it would fit here. In other words, I'd like to hear some words from someone with experience on these matters

Sorry for the long text & thanks for your time!
Spek

Posts: 66
Joined: Sat Oct 04, 2008 8:54 am