Release the limit of objects number

[Dongxueyang]

Hi guys:
Now the number of objects we can generate in our model is limted, which make it impossible to simulate a large scale model. So if you have some good idea for releasing the limit, you can make a comment any time.
All regards
Dongxueyang

[Dongxueyang]

@Oblomov
I have tried modifying the MAX_BODIES in src/particledefine.h.
I set the MAX_BODIES to 517 and generate 517 spheres in a model by add_sphere() function.
The simulation can be run.
But when I set MAX_BODIES to 518 and gengerate 518 spheres (objects), I failed and the simulation can not be run.

[Oblomov]

@Dongxueyang

currently the device reserves space in constant memory to keep track of the rigid body properties. Constant memory regions are limited to 64KiB in size, which is why you cannot increase the limit that much.

[Dongxueyang]

@Oblomov
I agree with you. And now I want to have a try to make some improvement, but where can I start from?
Is it possoble to change the place where store the rigid body properties？

Best wishes

[Oblomov]

To work around this limitation, object properties should be stored in buffers like just everything else. You would have to define new buffers (in src/define_buffers.h), determine when they are allocated (at this point, you can probably use the buffer mechanism both on host and on device), and then adapt the various setrb* functions to operate on the buffers instead of the constant-memory symbols.