Modifying a pixel image to have vector-controlled transparent patches

[Magicbean]

I'm having a hard time getting this to work - can anyone help?

I have imported a PNG file and I want to make vector areas to create patches of transparency. The intention is that I will export the PNG to another package, overlay my modified PNG with 'holes' in it and be able to see through patches of it.

In Photoshop, I would get similar end-result, just by deleting parts of the image so that the holes I created were transparent; this would  then show up as transparent holes in the exported PNG file.

In Affinity designer, I can create vector shapes through which I can see my image , but I want the opposite of that. I want the equivalent of an arbitrarily-shaped 'picture frame'. The frame should have my PNG image texture and the hole(s) in the frame should be transparent.

I have attached a simulated PNG which shows what I am trying to describe. The grey part is my PNG image. The dotted black lines enclose areas of transparency that I want to create and the red and white background just show what it would look like when exported into another file.

Any clues? Thank you.

 

[GarryP]

Welcome to the forums @Magicbean
I’m not sure if I have properly understood your requirements (I might have them the wrong way round) but it sounds like you want to use clipping, as can be seen in my attached video.
If that’s not what you want then just say so and we can come up with something else.

[thatGuy]

In Designer you can just use the Erase blend mode for your curves

[Magicbean]

@GarryP

Thank you, that is exactly what I was trying to do!

 

@thatGuy

That works even better for me because my vector shapes aren't converted to curves. For this particular application I need to retain the vectors.

 

Thanks both!

[MEB]

Hi Magicbean,
Welcome to Affinity Forums
Note that by using the Erase Blend mode all vector objects affected by it will be rasterised on export.