Real-Time Physics Simulation Forum

I'm going to kick off this with a question of my own. I opened up the demonstration file, attempted to make my own by copying the code into a file of my own. I imagine that documentation will take care of "you need a constraint variable for each axis for each object" blah blah.

Nevertheless, I noticed that if I use just the demo file, and delete everything except the white "rope" in the top-middle, it doesn't act like a rope when you click on any part. The bottom ball is constrained to its original location. how does one have free ends to simulate something like a hanging rope?

bmud wrote:I'm going to kick off this with a question of my own. I opened up the demonstration file, attempted to make my own by copying the code into a file of my own. I imagine that documentation will take care of "you need a constraint variable for each axis for each object" blah blah.

I was planning to add a ConstraintActuator, that should make things much simpler. Also, Ramon (rcruiz) is working on setting up constraint within the Blender user interface.

Nevertheless, I noticed that if I use just the demo file, and delete everything except the white "rope" in the top-middle, it doesn't act like a rope when you click on any part. The bottom ball is constrained to its original location. how does one have free ends to simulate something like a hanging rope?

The python script that handles clicking applies the wrong impulse. Will be fixed. Also, you can just remove one constraint, if you want to have a free end to the rope. I'll provide a better rope demo.

I'd like to know if there's a way to reduce or eliminate the spinning in a chain of constrained pieces. Its no good to have the parts of a chain independently spinning length-wise all crazy-like.

if such a thing was possible, i don't think I'd be having nearly as much trouble with this rope bridge

hello, you're only using 1 constraints per connection, which is no good . look at the brige I made from yours here :
plant.ffa.vutbr.cz/~novak/dwnflz/constraints.blend

look in the script constraint.py, where are the constraints defined. I reduced the number of objects(was too much, better doing a bridge from more planks in row, than having separate objects for rope pieces, etc.) I was planning to add bridges to my game anyway, so at least I know how to code it now. Look also at the pivot definition, it's important, since it defines the point where the objects get connected...

Hey, I just probably helped my competitor!

That's very curious. Now I'm confused as to what a constraint actually IS. a point (defined in the code by a local x/y/z coordinate from its axis?) where.... it's simply... connected to another object? That makes probably the most sense.

I'll conquer it yet!

p2p means point to point constraint, so yes, it's connection of 2 objects with 1 point, for the bridge you could also use the hinge constraint, which is defined by an axis/common edge of the objects.