Velocity direction from normal

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Hello!

This is kind of tricky. I just can't get my head around it.

Basically i have a grid which emits particles.
I want the particles to be emitted only along the normal direction of the grid.
So whenever i rotate the grid, the grid emits in the right direction.
The problem i am facing is that i do not have any initial velocity. I could set this in the Attributes Tab in POP Source but after rotation the Grid it would not emit in the direction i want it to, but in the fixed direction i entered

I tried to add attributes and use the normals in expressions. But either this will not work or i just didn't do the right thing…

Is there anybody out there who could help me, please ?
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Something like this?
Edited by Enivob - May 13, 2017 09:00:12

Attachments:
normals_as_velocity.gif (2.5 MB)
ap_grid_emit_particle_vel_as_normal.hiplc (206.7 KB)

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Almost i guess
I actually want to shoot a canonball every once in a while
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How about this

Attachments:
v_equals_N3.png (262.3 KB)

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maybe You´ll have to expose the Pointnormals first…

Attachments:
expose_N.png (244.0 KB)

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hey enivob, sorry, didn´t mean to be rude!
Just opened your file.
Wasn´t aware that it can be done in one go .
That´s probably the more elegant way.
@sebastianvfx: did another example,
maybe it helps.
cheers!

Attachments:
vEqualsNcannon.gif (94.6 KB)

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oh, and the hipfile

Attachments:
vEqualsNcannon.hiplc (703.1 KB)

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somehow reminds me of a power-up from “xenon2-megablast”
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