How make Paint.net-Multiply use zero for empty areas?

[me3]

When you make two layers and set the top layer to use Multiply as operator, Paint.net interprets the bottom layer as being 255 in all channels at the transparent (empty, the checkers) areas.

 

Is there a way to make it interpret an empty area as zero at all channels (black) instead?

 

I could work around it by just filling the empty areas in a bottom layer with black color. But then you can't really work with the shape (the opaque area), because when you cut something out, you need to refill black again, that's much work to do.

 

What ways are there to tint a white shape? I tried it with layers, but that's not working nice. And I disagree with paint.net on what it thinks transparent should mean to the multiply-operator, but maybe I'm wrong. What do other programs do in this case?

 

Thanks!

[MJW]

The way the Multiply blend mode treats transparent lower layers does see somewhat strange,  though I suppose it somehow makes sense. It doesn't matter what the transparent color is, transparent white or transparent black, so the first idea I thought of -- converting the transparent colors to transparent black -- wouldn't help.

 

I'm not sure what you're trying to achieve, but would adding a black layer as the lowest layer help?

[me3]

29 minutes ago, MJW said:

The way the Multiply blend mode treats transparent lower layers does see somewhat strange,  though I suppose it somehow makes sense. It doesn't matter what the transparent color is, transparent white or transparent black, so the first idea I thought of -- converting the transparent colors to transparent black -- wouldn't help.

 

I'm not sure what you're trying to achieve, but would adding a black layer as the lowest layer help?

This is genius!

There's no way it would not help, the black should go through to the middle layer just as if I had done that filling I wrote about.

I'll try... many thanks...

[me3]

Works! 🙂

Okay, I have black background instead of checkers, so tinting shapes to dark colors might be a bit hard to see, but it's a much better way already.

 

I think I have seen some checkbox in Gimp or Xara or an older Paint.net for corner case handling a thing like that. Like... "treat transparent as 0,0,0" or something.

 

If Photoshop would not force me to go online each month... I'm tempted to learn it. But not that way...

 

Anyways, it kind of works 🙂

[MJW]

You could use a gray or colored background layer instead of black. If you want to get fancy, you could use BoltBait's Grid/Checkerboard plugin to render a checkerboard background, similar to PDN's. Just set the mode to Checkerboard, and adjust the plugin's foreground color to a light gray. Th default size is about right.

[Ego Eram Reputo]

Would this plugin be useful?  Transparent to Transparent Black

[MJW]

8 hours ago, Ego Eram Reputo said:

Would this plugin be useful?  Transparent to Transparent Black

 

As much as I appreciate a mention of one of my plugins, the "color" of the transparency doesn't change how the Multiply blend mode treats transparency in lower layers. Transparent areas that would show the checkerboard pattern without the top Multiply layer are always treated as if they were white.

 

Actually, after experimenting with the other blend modes, it all makes sense. An opaque area in the top layer over a transparent area in the lower layers remains unchanged, no matter what the top layer's blend mode. So it isn't that the lower layers are treated as if they were white by the Multiply, any more than they're treated as if they were black by the Additive blend mode. They're simply left unchanged. There's really no reasonable alternative, if the top layer's pixels are to remain opaque, as they should.