I was wondering if there is a way to adjust the colors of the perspective guide lines
when using the new 3D Box tool. I am getting a Red, Purple & yellow by default (?)
The yellow is very washed out for me here and I hope I can alter it slightly.

No, I don't think it's possible. The only sort of workaround is to temporarily change the background in the area where you're working, to make the yellow more visible than it is on the default white.

GAngus wrote:I was wondering if there is a way to adjust the colors of the perspective guide lines
when using the new 3D Box tool. I am getting a Red, Purple & yellow by default (?)

They are hardcoded, IIRC. Try submitting a feature request for that. If path outline is configurable, then 3D box lines could be too.

brynn wrote:No, I don't think it's possible. The only sort of workaround is to temporarily change the background in the area where you're working, to make the yellow more visible than it is on the default white.

Hmmm.. that would work for me but,
I opened up the "Document Properties" window and setting a different color in where it says "Background"
does not seem to change anything.
Is there another place where I am supposed to change the Background color ?

Have you changed the opacity there? The default is fully transparent whatever hue you choose.

You can also create an object with some dark color fill and place it below the area where you have trouble seeing the line.

"create an object with some dark color fill and place it below"

Yeah, that's a handy trick, and is what I will use when/if I really need it.
After investigating on my own, a bit, it seems that all that white IS the transparency, right?
For a moment, I thought I could change the default.svg with a darker background but,
that may not work either, actually. That could get messy.
So, i'll stay with what I have.
'Thanks again

Yes when you open Inkscape the white canvas you see is actually transparent, but it's not represented as checkerboard pattern as in other graphics applications. You won't see a difference on screen in Inkscape window if you have white color as bg or transparent.

In Document properties when you click on the top right color box to change the background you have to make sure to make the A box 255 and not 0 to make it opaque, and you won't see a checkerboard pattern in half of the color box anymore either.

Aahh, So I CAN change my background color in the window I am working in.
I didn't know that about the 255. that solves my whole problem.
I didn't realize there were actually 2 choices there, I guess.
That's it, I really have to go through all of the documentations again.
You have been so helpful, Thanks