I'm stuck trying to display a set of particles using jit.gl.render with input from a matrix containing particle coordinates (and later rgba info).

A simplified problem I have trouble with is:

In Jitter tutorial 46, replace the js object by "jit.noise 3 float32 1000".

I thought that this should produce randomly positioned particles at each frame, but it doesn't produce any output. Same thing occurs if I supply a constant, random matrix (of the form "3 float32 100" or whatever).

Can someone explain to me what I'm doing wrong?

In Jitter tutorial 46, replace the js object by "jit.noise 3 float32 1000".  

I thought that this should produce randomly positioned particles at each frame, but it doesn't produce any output.  Same thing occurs if I supply a constant, random matrix (of the form "3 float32 100" or whatever).

Can someone explain to me what I'm doing wrong? 

jitter-particles-interface-problem

> A simplified problem I have trouble with is:

> In Jitter tutorial 46, replace the js object by "jit.noise 3 

> I thought that this should produce randomly positioned particles at 

> each frame, but it doesn't produce any output. Same thing occurs 

> if I supply a constant, random matrix (of the form "3 float32 100" 

> Can someone explain to me what I'm doing wrong?

You probably need to specify the draw primitive for jit.gl.render. 

case "points", but jitter operators just send jit_matrix 

. Otherwise it is trying to render using the current 

jit.gl.render @primitive value. It is probably still the default 

"tri_grid", which assumes a grid layout (2 dimensions). You might 

want to check out tutorial 37, "Geometry Under the Hood".

Btw, you might also want to play with jit.gl.multiple, or jit.gl.mesh 

> A simplified problem I have trouble with is:
>
> In Jitter tutorial 46, replace the js object by "jit.noise 3  
> float32 1000".
>
> I thought that this should produce randomly positioned particles at  
> each frame, but it doesn't produce any output.  Same thing occurs  
> if I supply a constant, random matrix (of the form "3 float32 100"  
> or whatever).
>
> Can someone explain to me what I'm doing wrong?

You probably need to specify the draw primitive for jit.gl.render.  
The JS outputs jit_matrix  , in this  
case "points", but  jitter operators just send jit_matrix  
. Otherwise it is trying to render using the current  
jit.gl.render @primitive value. It is probably still the default  
"tri_grid", which assumes a grid layout (2 dimensions). You might  
want to check out tutorial 37, "Geometry Under the Hood".

Btw, you might also want to play with jit.gl.multiple, or jit.gl.mesh  
for this sort of thing.

Thanks! I would have caught this, but jit.matrixinfo and jit.print seem to work as if there was no appended primitive type message.

I believe I will move what I have to the Javascript interface, which is very useful.

Thanks!  I would have caught this, but jit.matrixinfo and jit.print seem to work as if there was no appended primitive type message.

Jitter particles interface problem