Copy layer values into a mask?

[spacecat]

I have a shading layer here that only has grey/white/black values. I wanted to copy these same values but as a mask to an existing layer, how can I do that with affinity? 

 

[NotMyFault]

1. Duplicate layer
2. Rasterize to Mask (right-click on layer / context menu)
3. Move mask layer nested as mask to the layer you want it to be applied

[spacecat]

Thanks for the reply. But is it possible to move this rasterized mask to replace the mask of HSL? 

 

[NotMyFault]

Yes, there are several ways. Try this:

1. Ensure that the channels panel is visible (View>Studio>Channels)
2. Select the mask layer in the layers stack
3. In Channels panel, right-click on "Mask Alpha", choose "Create Spare Channel". It creates a new channel at the bottom of channels panel
4. Select the HSL adjustment layer in the layers stack
5. In Channels panel, right-click on the spare channel created before, and choose "Load to HSL Shift Adjustment Alpha"

 

[spacecat]

That's odd, at first your suggestion didn't work ...  If I use any grey/black layers it gives me an empty mask. But if I use any other color or white, your suggestion works fine. I wonder if this feature is by design(?) 

I had to do a workaround by Inverting that shading layer to white values ... now it works : ) 

[NotMyFault]

16 minutes ago, spacecat said:

That's odd, at first your suggestion didn't work ...  If I use any grey/black layers it gives me an empty mask. But if I use any other color or white, your suggestion works fine. I wonder if this feature is by design(?) 

I had to do a workaround by Inverting that shading layer to white values ... now it works : ) 

The most important step is to "Rasterize as Mask". Affinity handles regular RGB pixel layers and Mask completely different, despite all based on numeric values between 0-255 (or appropriate upper limits based on 8/16/32 bit depth). You can convert between them with help of some arcane magic like Spare Channels, Channels Adjustment, Procedural Texture Filters, but Affinity tried - and unfortunately absolutely succeeded - to make this even more complicated and un-intuitive as i could image in my worst nightmares. I especially hate the Channels Panel, as it requires such a painful toe-dance between layers, channels, right-mouse and select from 10s of sub-menu items ...