Bug: nanovg intersectScissor doesn't propagate to child widgets

[dromer]

As discussed before I tried to solve it with this patch: https://github.com/DISTRHO/DPF/pull/521/changes

Left is the current behavior, right is what is expected/wanted:

[dromer]

Hmm, now I'm confused.

I tried to create a minimal test plugin: https://github.com/dromer/dpf-nanovg-scissor

And this is the result:

As you can see the subwidget (which draws just a green canvas past the parent borders) is intersected correctly by the parent border. Even when I disable the intersect operation!

And then the parent border is drawn around the child widget somehow, which is even stranger to me.

So now I have even less of a clue of what's going no here 🤔

[dromer]

Ok sorry, I updated the example with a more similar setup as I have. There is a "main patch" that envelopes the entire UI as NanoSubWidgets. The Subpatch then is a NanoSubWidget that contains more levels of NanoSubWidgets.

When we do this I think we can reproduce the issue:

So the issue seems to be with NanoSubWidget being a parent to other NanoSubWidget objects.

When I apply the patch we get the correct scissor on child objects (hmm, although here it looks more like it's translated?):

(although this border still seems odd to me. maybe I didn't notice it before because of the color)

[dromer]

Just to update with my current use-case:
https://github.com/Wasted-Audio/pdvg-example-plugin/
https://github.com/Wasted-Audio/pdvg

The idea here is that we can construct "subpatches" which contain widgets. The subpatch is parented by either a main patch or another subpatch that is a level above.