Can't get rid of white lines in repeat pattern design on Affinity Designer

[LydiaTheIllustrator]

Hi, I've been trying to get rid of these white lines that keep showing up in my art boards, where I've repeated a tile converted to a symbol with a design inside it. The repeat design itself is perfect, everything is set to pixels and theoretically matches up exactly, so I don't understand why these white lines are appearing.

They don't disappear when I export as JPG or PDF. I am a surface pattern designer and love the live update feature across repeated symbols. But I can't export the repeat pattern as long as these white lines are there. 

I've looked around online and found many others with this issue in Affinity but can't find any conclusive way to fix it. I'm running the most recent version of Affinity and Mac OSX, so there's some sort of discrepancy in the software...

[GarryP]

Welcome to the forums @LydiaTheIllustrator

[Below, when I say 'container layer' I mean the specific layer you are converting to a Symbol which 'contains' the parts of the pattern you are wanting repeated.]

The first thing to check is that the 'container layer' has all integer X/Y/W/H values before you make it into a Symbol.
If you don’t do that then all of the symbols can be slightly ‘misaligned’.
(Go to Preferences / User Interface and set all the Decimal Places settings to more than 3 as a further check.)

The second thing to check is that the ‘container layer’ that you are converting to a symbol has no Quick Effects (or Live Filters if you have used Photo) applied to it.
Various Quick Effects (and Live Filters) can make the layer larger than the layer size and that can sometimes cause trouble.

Also check to see if the ‘container layer’ has a Stroke applied to it.
If it does then it needs to be aligned to the inside, otherwise that will affect things.

If you have rotated your symbol then it will usually be difficult to get a ‘perfect’ repeated pattern without various extra manual steps (Blend Options, giving the pattern a ‘background’, etc.)

If none of this helps then if you can share the document with us we can have a look to see if we can get it looking better.

[Old Bruce]

The best way is to toggle the x, y, w, and h up and down by using the transform panel and the arrow keys on your keyboard. While setting the preferences to show 3 or 6 or more decimal places if often mentioned it is not a solution.

For Pixel accurate work: Disengage the Move by Whole Pixels in the snapping list. This is a real pain as it is on by default. Turn off snap to midpoints for any and everything that has it. In essence you want Force Pixel Alignment on and everything else off.

[NotMyFault]

In case you export as raster format, the cure is very simple:

1. add a levels adjustment as top layer
2. choose alpha channel
3. set white level to 0 (zero)

this will boost all semi-transparent pixels to fully opaque, keeping the color (mainly anti-aliased from neighboring pixels), but leave fully transparent areas untouched.

 

Edited December 30, 2022 by NotMyFault
Added „fully“

[thomaso]

7 hours ago, NotMyFault said:

but leave otherwise transparent areas untouched

This works nicely to remove the white lines at vector edges … but how do you mean it leaves others untouched? It appears to affect any transparency, e.g. layer transparency. The upper setup is above the adjustment and not affected and thus shows the semitransparent edges in the pink squares, the lower setup shows this edge transparency only on the blue rectangle. Both blue rectangles have 75% layer opacity. – Interestingly the pink 'tool transparency' is not affected by the adjustment where objects are below – can you explain why?

[NotMyFault]

I’ve edited my post for clarity: the adjustment keeps fully transparent areas untouched, and changes all semi-transparent areas to fully opaque. 

[NotMyFault]

8 hours ago, thomaso said:

Interestingly the pink 'tool transparency' is not affected by the adjustment where objects are below – can you explain why?

If you use 2 overlapping areas with 75% alpha, the blend formula will result in much higher alpha, almost opaque.

[henryanthony]

@LydiaTheIllustratorany chance you could post an example as an image and a file? If your work is proprietary, perhaps you could make a “generic” example that illustrates the defect. I am interested because I am working on tiled patterns. I have yet to create any work thus far because I have only been working with Affinity Designer and Photo for a few days. Thanks!

[NotMyFault]

Older tutorial about the issue

 

[henryanthony]

This seems to be a common problem.

 

[LydiaTheIllustrator]

Thanks everyone for your help! @henryanthony I've been playing with adding a stroke in the same background colour to the container symbol shape layer and so far that seems to be working. Just need to double check all my assets will clip to it without the stroke being applied over the top, but I think I'm on the right track...

[henryanthony]

I've done a little research on this and found that Photoshop and other programs have the same issue. So, I guess workarounds are required.