Additional PNG export transparent color option

[Corgi]

I'm working with a transparent background on a moderately complex graphic that I'll end up exporting to PNG. There are portions of the graphic that I want to make completely transparent, but presently (AFAIK) to do so within Designer would require extensive, annoying work playing around with things like Subtract operations on the many geometric shapes I have.

What I was looking for in the Export dialog was the ability to choose a color to make transparent (in addition to the already-transparent background) during export, but I don't see that option. 

My solution has been to export to PNG, then open the resulting file in Photo and doing Flood Select (zero tolerance) and deleting the color I want to be transparent. That gets precisely the result I am looking for, but it would be far easier if this could be done during the initial export.

 

[Alfred]

51 minutes ago, Corgi said:

My solution has been to export to PNG, then open the resulting file in Photo and doing Flood Select (zero tolerance) and deleting the color I want to be transparent.

There’s no need to switch to Photo for this. There’s a ‘magic wand’ Flood Selection Tool in the Pixel persona of Affinity Designer.

[Corgi]

Quote

There’s no need to switch to Photo for this. There’s a ‘magic wand’ Flood Selection Tool in the Pixel persona of Affinity Designer.

I tried that, but the Flood Selection tool doesn't work on vector images. Everything is in vector format, and the only rasterization is done when I export. Yes, I could rasterize the image first and then use the Pixel persona, but then I'd have to undo or revert the rasterization afterwards. So that's still an inconvenient process.

[Old Bruce]

2 hours ago, Corgi said:

There are portions of the graphic that I want to make completely transparent,

May be a dumb question here but... Why have those visible before you export? Meaning turn them off in the Layers panel.

[walt.farrell]

37 minutes ago, Corgi said:

I tried that, but the Flood Selection tool doesn't work on vector images.

Technically, he only said you didn't need to switch to Photo. He didn't say you could avoid exporting to PNG

39 minutes ago, Corgi said:

Yes, I could rasterize the image first and then use the Pixel persona, but then I'd have to undo or revert the rasterization afterwards.

Why would you have to revert the rasterization? You're exporting to PNG, anyway, which is all raster.

[Corgi]

2 minutes ago, Old Bruce said:

May be a dumb question here but... Why have those visible before you export? Meaning turn them off in the Layers panel.

It's only portions of layers that I want to hide. For example, I have various shapes with both fill and stroke, and on some of the objects I need to hide portions of just the stroke. But now I'm trying to use vector masks to accomplish what I want, although it still seems like it might be easy to add the export feature I described.

[NotMyFault]

I could provide a procedural texture filter which makes all pixels of one specific color (a RGB color code, e.g. 123 / 222 / 213) transparent.

The color code needs to be entered either as (three) numeric input values 0…255, or via sliders.

• interested?

As others already said, png is a raster format, so it will do no harm. You could apply this filter as top layer and activate only for export.

Interested?

 

[Corgi]

2 minutes ago, walt.farrell said:

Technically, he only said you didn't need to switch to Photo. He didn't say you could avoid exporting to PNG

Why would you have to revert the rasterization? You're exporting to PNG, anyway, which is all raster.

I'm going to need to continue tweaking my design over time, which of course I'd like to do in vector mode until the very last step each time. So it just doesn't seem like that would save effort. Don't get me wrong; the feature I'm requesting would save me time, but not a lot of time, since it's easy to fix post-export. It's only that it seems like an easy and handy feature to add.

However, I'm seeing if vector masks will do the trick for me without needing post-export repair.

Thanks!

[Corgi]

5 minutes ago, NotMyFault said:

I could provide a procedural texture filter which makes all pixels of one specific color (a RGB color code, e.g. 123 / 222 / 213) transparent.

The color code needs to be entered either as (three) numeric input values 0…255, or via sliders.

• interested?

As others already said, png is a raster format, so it will do no harm. You could apply this filter as top layer and activate only for export.

Interested?

 

Wow, that's very kind of you to offer! There's no need for you to go to the trouble, but I really appreciate it. I think that the vector masks will work for me, even though they're turning out to be awkward and inconvenient (at least until I learn how to use them properly 🙂 )

[NotMyFault]

Here is the file. Just create a preset from the PT filter for easy reuse.

To adjust the color you want to be transparent, simply open the PT filter and change the RGB input values.

When you activate the filter, all pixels of exact the selected color become fully transparent. All other pixels stay unchanged.

 

Works only for RGB/8. Could be extended to work in other color formats or RGB/16.

 

Make one color transparent.afphoto

[Corgi]

Quote

Here is the file. Just create a preset from the PT filter for easy reuse.

Wow, thank you very much, @NotMyFault!