"Ghost" outline showing through mask

[Mr Lucky]

maybe I'm doing this wrong, but I have a mask in place to remove part of a curve, but there is a kind of outline showing. 

My understanding is that the white rectangle, as a child of the black shape, should be masking it completely, yet there are faint outlines of the black shape.

 

 

Can anyone help please? Thanks

 

[Move Along People]

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[Mr Lucky]

Thanks, that was easy.

 

Why would anyone not want precise clipping I wonder?

[Gabe]

Hi both,

On complex design, precise clipping will slow down the preview, because it has to render this on the fly. That checkbox is only a preview option, as, during the export, it will always precise clip. 

Thanks,

Gabe. 

[Mr Lucky]

Problem:

 

I have enabled precise clipping (in both AD and AP) but the lines are still showing on one file.

 

And they are there when exported to PDF

 

EDIT: solved! I needed to make the masked area larger 

 

octave-logo-CS.pdf

[JimmyJack]

4 hours ago, Mr Lucky said:

EDIT: solved! 

 

You still have all the thin lines in the PDF.

BTW: In your original image your objects aren't in the mask position they are in the child clipping position.

[Mr Lucky]

2 hours ago, JimmyJack said:

You still have all the thin lines in the PDF.

Yes, the PDF was uploaded before the edit. I solved the issue since that PDF

2 hours ago, JimmyJack said:

BTW: In your original image your objects aren't in the mask position they are in the child clipping position.

Please explain, I used that method as I didn't know any other way to remove part of the curve. Can you please explain the mask position ? Thanks. Will it do the same thing?

[lepr]

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[R C-R]

22 hours ago, Mr Lucky said:

I have enabled precise clipping (in both AD and AP) but the lines are still showing on one file.

If the file is like the one shown in your first post, that may be because the black parent layer has a stroke. Since the white rectangle is its clipped child, the stroke won't be hidden. Remove the stroke & the lines should disappear:

Ghost outline.afdesign

 

On 2/4/2019 at 7:01 AM, GabrielM said:

That checkbox is only a preview option, as, during the export, it will always precise clip. 

That's what I thought, but exporting the above Ghost outline file using (for example) the PDF (for web) preset, I get Ghost outline clipped precise.pdf, which has a 'ghost' outline, apparently because of a mask layer that was added during export:
 

Hiding or deleting that Curve mask layer removes the ghost outline. Why?

[lepr]

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[R C-R]

3 hours ago, >|< said:

Anti-aliased edges of the black shape are partially revealed by anti-aliasing of coincident edges of the overlying white shape that results from the masking of the white rectangle.

Because you then have the entire white rectangle visible and completely covering the aforementioned anti-aliased edges of the black shape.

It probably was not clear but my "why" question is why does the Affinity pdf export add the mask? From what I can tell, the PDF (for web) preset does not preserve transparency no matter how I combine the two shapes, so it seems kind of pointless to add the mask. 

[lepr]

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