drawing a string (jit.phys.multiple to jit.path_to_jit.gl.path)

phiol's icon

Hi all,

I believe I'm close to it (maybe not) but not quite there.
I want to use jit.gl.path to draw a string
that would be traced by jit.phys.multiple @constraint point2point
using the @constraint_matrix 1

I've tried to make my patch super clear using colors.
I want the green section to talk to the blue section.

Any help would be greatly , greatly appreciated.

Max Patch
Copy patch and select New From Clipboard in Max.

thanks a million

Rob Ramirez's icon
Max Patch
Copy patch and select New From Clipboard in Max.

you simply need to send the position matrix out of phys.multiple to the input of jit.gl.path

phiol's icon

Man that 's great! thanks Rob!! I knew I was just an inch away from the answer.

I'm gonna post my patch hoping it can help other users in the future.

I think that a similar patch to this one could be a good one to include in the Max/examples/Jitter-examples/render/physics/ folder.
using jit.gl.path.

Important topics covered in this patch

- Jit.phys.hinge as an anchor point for rigid bodies

- *** the very important @body1 name_0_0
- hiding specific jit.gl.gridshape bodies using jit.matrix and [pack setcell 0 0 val f f f f] message
-and of course , using the constraint_matrix (from jit.phys.multiple) to draw a line with jit.gl.path.

Notes:

Jit.phys.hinge as an anchor point

- jit.phys.hinge crashed my patch quite a lot when I sent it a "reset" message
-In the end , I got it to work but I really had a hard time creating 2 separate hinges as
an anchor points. (I discovered a 2nd hinge won't appear unless there isn't a @body1 included)

Thanks again Rob

attached is the patch and a jit.matrix saved file that hides the 2nd & 3rd sphere

physical_string_w._anchoir-point_hinges.zip
zip
pry's icon

Hi Phiol,

Just a comment : in your patch, this is not the constraint_matrix which is used to draw line but the position_matrix of the rigid bodies from jit.phys.multiple. So you don't need to set the constraint_matrix attribute to 1.
constraint_matrix is sent from the right output of jit.phys.multiple (dumpout).
Have you seen this topic : https://cycling74.com/forums/jit-phys-vs-pmpd-vs-msd/ ?

Regards,

Pry

phiol's icon

Thanks a lot pry ;-)
That post is 3 months old. Been doing quite a lot of patching
since. It(my approach) naturally became what you mentioned.

Side note: One of my favorite use of the @constraint_matrix 1, is to
create blankets using jit.gl.nurbs. with anchor points using phys.hinge.

Or no gravity at all and create a sorta origami of a png.

I'm sure you get what I mean :-)

Still, thanks for the heads up though..

phiol