### Author Topic: How to random seed for each tile in UDIM mode?  (Read 961 times)

#### llcn712

I have created a material shared to 5 tiles using s.d UDIM flow.
However, I found it is a bit annoying that I need to change seed for each tile before export each tile texture
Is there any function/  feature that sets different random seed of a graph for each tile?

#### luc.chamerlat.allegorithmic

Hi,

You can try to expose your random seed as an empty function and play with the UV_tile (int2) value

I multiplied the X value by 150 in order to make sure that you will never have the same seed. Without this operation, your seed will be the same for 1002 and 1011 ([0;1],[1;0]).
Q.A Analyst

#### llcn712

I am new to s.d. and got some more stupid questions.

1) What do we get when we swizzle \$uvtile ? e.g in udim 1001 ,we will get (0,0)?  udim 1002, we will get (1,0)?
in udim 1001 (0,0), applying the function, we multiply 150 on x then plus y   0 x150 + 0 =  150,
then we will get 150 for udim 1001 random seed?

2) How to get the uvtile(get Integar)in function graph ? Because I can't see uvtile in built variables.
https://support.allegorithmic.com/documentation/display/SDDOC/Built-in+Variables

3) Can I expose this in the random seed in graph basic parameter instead of each noise?

4) left down corner of the function graph said "expected output type is integer 1 "
which means there will be 2 integer output? However, we just require 1 number for seed, right?

Cheers,
Chuen
Last Edit: May 16, 2018, 05:30:16 am

#### luc.chamerlat.allegorithmic

You're welcome !

1- So in this example, the final output will be

1001 : [0,0] = (150*0)+0 = 0
1002 : [1,0] = (150*1)+0 = 150
...
1011 : [0,1] = (150*0)+1 = 1
1012 : [1,1] = (150*1)+1 = 151

2- You just need to add a "Get Integer2" inside of your function, then you will be able to choose "\$uvtile" from the drop down list. As we recently added this variable, we might have forget to add it to the online doc. I'll have a look to it thanks !

3 - It should be possible and maybe the best way to randomize your noises for each tile, however I tried it and it seems to be broken for now. I have informed the dev' team and I'll come back to you once I get the information.

4 - As the random seed is an integer1, you can't drive this value with a float or integer2 for example. The \$uvtile variable is an integer2, as I swizzle it and add the U to the V value, the final output is an integer1.

Hope it helps !
Q.A Analyst

#### llcn712

3. Yup, I tested in a noise node, it is working, but it's not working in master random seed. Please let me know if it is fixed, it is quite urgent to me, it's really killing me when I have to manually change the seed and then export 1 tile each time,,, hahah

1,2,4 are clear!

Thank you!

Cheers,
Chuen

#### luc.chamerlat.allegorithmic

Glad to know it helps ! I'll send you a PM when the random seed function will be fixed.
Q.A Analyst

#### geoffreydiamond

Hi there,

Thanks for posting this solution, it works very well on the individual noise nodes; however, it seems as though it still does not work on the master Random Seed parameter. Are there still plans to get this fixed? Thanks!