# \$F to be a certain frame, Not 1

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Hi guys,

As i have pre-roll in my simulation, i am starting my sim from 1000th frame. but this is creating a problem, when i am using the "\$F" , because i know it is recognising as frame 1.

so that is the help i am looking forward here. how do i fix that ?? i want this \$F to be the 1000th frame not the usual first frame.

if suppose, there is no solution for that , then all i want is...

"""i have 100 rigid pieces, and i want each frame to have different pieces staring from 1000.""". i type in piece\$F in the blast node, and its starting from frame 1.

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There is a companion global variable called "\$SF". This is the simulation frame number, Try using that instead. All frame based expressions you use inside a simulation should use \$SF, not \$F.

Edited by Atom

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1 hour ago, Atom said:

There is a companion global variable called "\$SF". This is the simulation frame number, Try using that instead. All frame based expressions you use inside a simulation should use \$SF, not \$F.

so if \$F is 1,2,3.....

and my 'sim' substeps is say 10...does that mean \$SF is 1.0, 1.1, 1.2....?

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11 hours ago, Jamshid63 said:

"""i have 100 rigid pieces, and i want each frame to have different pieces staring from 1000.""". i type in piece\$F in the blast node, and its starting from frame 1.

cant you do piece(\$F+999)?

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9 hours ago, Atom said:

There is a companion global variable called "\$SF". This is the simulation frame number, Try using that instead. All frame based expressions you use inside a simulation should use \$SF, not \$F.

I tried both \$SF method, and \$F+999, still no good.

7 hours ago, Jesper Rahlff said:

cant you do piece(\$F+999)?

Instead tried file caching the blasted node which starts from frame 1 and used time wrap node to start from 1000th frame. it works.

But i am sure, there must be an easy way.

i have attached the .hip file , in case if you guys didnt understand what i am trying to say .

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here...so you see in my Blast...if I start at frame 100, I put in -99

in your case put in -999

So if you want the one piece to be NOT deleted and blast the rest..then of course simply put a ! infront, ie.

!@name==`piece+(\$F-999)`

(oh..of course, delete non-selected too....silly me)

Edited by Noobini

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I modded your file, scrub from frame 1000 to see,

I'm not sure if your setup is right tho...you've got debris, then you've also got class...you might wanna tweak a bit....

EDIT: added a switch in so all is there up to 999, then it starts blasting...

framestart_problem_mod.hipnc

Edited by Noobini
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Thanks alot.

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