The problem with the 'Rotation' operator

[cgdvs]

Hi,Tyson!



When I cancel the 'Effect particles shape orientation' option of the 'Rotation' operator, the entire animation will be much slower. I can clearly feel it
This is just a test file, and in a real project, the number is much larger than it is now. Even after caching, it is still quite sluggish. If this option is not activated, caching is very fast
Why do I suspect this is a bug, because the 'Rotation' operator effect only affects once. However, the lag is persistent
I'm not sure if this must belong to BUG. Please check. Thank you

[tyFlow]

Hi cgdvs,

It's not a bug - when you uncheck that setting, all affected particles are converted into unique meshes, in order to properly orient their mesh to match your Rotation settings. In other words, when you disable that setting, instancing is no longer possible...this will cause slowdowns if you have a lot of particles.

[cgdvs]

Hi cgdvs,

It's not a bug - when you uncheck that setting, all affected particles are converted into unique meshes, in order to properly orient their mesh to match your Rotation settings. In other words, when you disable that setting, instancing is no longer possible...this will cause slowdowns if you have a lot of particles.

Oh, I see. Thank you for your explanation

There is a problem, as in the case study. I want to make the direction of the grass more random, so I must use "Random horizontal". At this point, I need to create a rotation animation for the particles based on the "world X-axis direction". At this point, the rotation is "local coordinates". This is why I want to cancel this option. Is there a way to reset the coordinates of the particles? What I mean is to keep the previously chaotic coordinates unified again. Of course, the shape and direction of the particles cannot be changed. Can this be achieved?

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If you don't understand what I mean, please take a look at the picture

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forum upload failed. I will send the image here:
https://scontent-tpe1-1.xx.fbcdn.net/v/t...e=650F45A3

[tyFlow]

You can parent your grass to other particles with Set Target...rotate the grass but do not rotate the parents...then assign the animation to the parent particles...the child (grass) particles will follow, along with their rotation offset.

[cgdvs]

Okay, that's a good idea. I will test according to the method you provided. Thank you again

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You can parent your grass to other particles with Set Target...rotate the grass but do not rotate the parents...then assign the animation to the parent particles...the child (grass) particles will follow, along with their rotation offset.

I tested successfully and your method is very good. Thank you