OPE, Glue groups and Physics Joint Help: **UPDATED | Forums

[rlmergeuser]

Hey guys.

I'm having some problems...

***Updated***

I've made a glue group involving a heap of bent ramps making a large mechanical wheel. I want to move the group into the riders path using OPE. Once the rider is inside the 'wheel', one of the ramps hinge and closes causing the 'wheel' to be complete. Then the whole wheel rotates on a hinge. The Angular Velocity of the wheel caused by the rider accelerating makes the whole assembly rise vertically using a physics joint slider. Once a set height is reached, the original hinged part reopens allowing the rider out.

The problems are this.... I can make both physics joints move fine (the hinge and the slider) OR I can make the glue group move with ope perfectly. However... If I use OPE, then try to run the physics joints, they wig out and the hinges move all over the place causing the hinge pivot points to fault.

At times, this has also caused the game to crash giving me either freezes or black screens.


So far: What i've figured out (and realistically is fairly obvious), If the wheel is one complete glue group, using physic joint inside it wont work because physics only works on individual items or entire glue groups - you cant sub select an item of a glue group as a physics joint target (or so it seems). I tried using three OPE's - one for wheel, one for the ramp that hinges and one for an item that the ramp hinges around. However, still much the same. From there it just gets really bloody complicated because I have 3 objects that have to both rotate and slide at the same time. Not only that, they have to stop their movement and then one hinge has to have its motor reversed.....

I'm sure i'm making this a lot harder than it needs to be. Can anyone shed some light or maybe an idea?? PLEASE!!

[dasraizer]

maybe try using a physics joint as an ope by pointing the upper and lower limits to a variable, i make things rotate that way , i've not played with sliding the upper/lower of the linear position tho, also teleporting a glue group with physics joints attached is not good, as the joints pivot does not (to a degree), making its restitution funk out.

its tricky, im still figuring out the sequencing and how things work myself, good luck, this sounds like an interesting project.

[rlmergeuser]

The story so far...

i tried setting a simple single axis rotating hinge targeting two objects: A tractor wheel and a dummy object.

I them made the hinge into a motor with all standard setting.

Turn wheel physics ON and hit [select] to test physics

Hinge works fine.

turned physic OFF on wheel

I then used 2 OPE. One targets the Wheel, one targeting the dummy object.

I set the ope to move both items at the same time (using a trigger splitter) 2 metres on the same axis.

Off the same splitter, I used an impulse delay of 1 second to turn on physics for wheel.

Epic Fail. Wheel will not rotate.

**Both items and the hinge pivot all move relative to each other perfectly but something is failing.

Can someone please try this and give me some feedback. I'm sure it can be this hard

[dasraizer]

hmm, are you teleporting far or like an elevator?

also OPE's can point to more than one target

the problem is the joints is not teleporting, and if its restitution is set wrong or physics is off, its not going to move or take its time getting to the hinge location, if thats even posible, it could be underground!!

If you are just moving the objects smoothly, i would just motor the linear, also try putting the physics joint on point-to-point and hard with custom set.

edit: or you can just duplicate your objects at the new location and forget teleporting.

[rlmergeuser]

I stopped. Went back to school and looked through the tute videos again. Thank the lord for Shogun!!!

I'll have a play again later today (after I get back from work) but it looks like a single physics joint should be able to do it. If I make it 'User Defined', I have all options opened - Linear, Angular and Spring. With the right amount of data sources, Impulse delays/splicers, I SHOULD be able to make the physics joint move Linear (slider) on the X axis, then Rotate AND slide on the Y or Z axis as needed.

If I get it to work, I'll take a photo/video and post it.