How I can find the seamless pattern tile size?

Would that not have to be (short side + long side) by (short side + long side)?

Then you may want to start giving some relevant information:

Did you change the Scale from 1?

Did you set some Spacing?

What are the Pattern’s exact dimensions (as indicated by hovering over the Pattern like JJMack showed)?

Could you please post a screenshot taken at View > 100% of the result?

I also have tried several different options: for example long side*2 (3, 4, 5 etc.) by short side*2 (3, 4, 5 etc.).

As the weave combines short and long side in both directions those approaches would probably only work if the long side was a integer-multiple of the short side.

1280px x 1280px?

Could you please post a screenshot of the resulting pattern taken at View > 100%?

Hi

If a pattern is tiling on your image you can find it fairly easily by duplicating the layer - setting the blend mode of the top layer to difference then dragging the top layer across and down until it turns completely black. At that point it is repeating

Then drag across a couple of guides and read the tile size from the ruler (see example below)

However , the script does not have to tile across the layer. Each small sub pattern in the example you gave can be in any of 2 rotations in a block of 4. So if your layer only has room for a block of 2x2 as below then there are 2x2x2x2 = 16 different ways of arranging those sub tiles.

If you have room for 16 across x 16 down then that can be arranged in 2^256 =1.15 x10^77 (i.e. approx. 1 with 77 zeros after it). So that pattern may well not repeat i.e. be tiled on your layer.
The numbers get even bigger use the random brightness and color options.

Of course if you need to make a tile for use elsewhere you can do so by cutting the pattern where it is a close fit. Using Filter > Other >Offset to move the layer 50% down and 50% to the right, which moves the edges to the centre, then repairing any edges that do not match with the clone tool.

I hope that helps you

Dave

I had not noticed the flipping …

You're welcome

Dave

c.pfaffenbichler  wrote

 

I had not noticed the flipping …

I must admit I had assumed it would be simply tiling groups of 4 or 16 or whatever - but when I tried the difference method and couldn't get it to go black, I looked closely and realised it was better than that

Dave

Do not forget youy can file any selection with a patters it need not be a rectangle area. The pattern will be trimmed to the area. A rectangle pattern tile can not fit the area perfectly.  Tiles will be trimmed.