Circuit wires are hard to see

[Selvek]

TL;DR

Red and green wires are small and hard to see and often blend in with combinator art.

What ?

It's pretty hard to tell what's going on in a large combinator setup because red and green wires start blending with the combinator art and sometimes overlap.

In the screenshot:
1) Combinators C and F have additional (visual-only) green wires as part of the artwork that appear to connect to the "real" wires. For example, see the green wire from the output of C to the input of D - it passes by an "artwork" green wire which makes it appear to connect to the input of C.
2) The two fast inserters are connected with both red and green wires, not that you would know it by looking.
3) The green wire from the coal chest to the input of E passes by the output of C - does it connect? It's visually a bit ambiguous.
4) An overall size increase on the wires might be helpful too (or a toggle option that thickens all wires so you can turn it off when not working on circuits)

Suggested changes:
1) Remove all the (visual-only) red and green wires from the combinator artworks. Make sure combinators have no visible red or green to conflict with (real) wires. (This would be more work programming-wise, but perhaps the amount of "droop" in a wire could be automatically adjusted to prevent it from passing over the connection point of another entity?)
2) Make sure there is a really distinct art change when a connection is made compared to when a wire just passes over a combinator without connecting.
3) To make sure red and green wires don't cover each other up, change it so e.g. red wires always connect in the lower left corner of a tile, and green always connect in the upper right corner.

Why ?

Combinators are tricky enough as is without struggling to tell easily what is already connected. You can mouse over a connection to highlight wires, which certainly helps, but it is really important to be able to see all wires clearly all the time for comprehending large circuits. Even just altering the combinator art without any other changes would go a long way toward reducing the visual clutter.

[Deadly-Bagel]

I think red wires also need changing to blue. Red is an extremely difficult colour for many to see, especially when on a green or brown background.

[Tekky]

Red is an extremely difficult colour for many to see, especially when on a green or brown background.

According to this Wikipedia article, about 7% of males of North European descent have a red-green color blindness.

Related thread about color blindness:

viewtopic.php?f=6&t=43120

[Deadly-Bagel]

Depends on who (and how) you ask. I've read studies that suggest 20-40% of males have colour deficiency, but many or most cases are simply so minor they go unnoticed. The figures listed on that article are those "affected" by it, not those "with" it.

Generally people see different levels of colour, eg while I'm not totally blind to red or yellow it is extremely difficult for me to pick them out in most circumstances, especially at a glance. On the other hand my uncle is totally red-green colour blind.

Where am I going with this? Well if you've got a great big blob of red comparing it to a contrasting green, yeah probably 95%+ would be able to instantly distinguish the difference. However, with a tiny thin red wire over a low-contrast green and/or brown background with a bunch of other colours and shapes around, you could expect that to drop to 90% with another 10-20% having some difficulty, even if they don't realise it. If you've never known different, what is there to compare it to? For many years I assumed I still had to learn colours to recognise them and my impairment is quite strong.

Change red wires to blue, everyone's happy.

[Selvek]

Yeah I specifically avoided mentioning color blindness since I'm not an expert on it and I know there are already color-blind friendly mods. I think reducing the clutter is relevant whether you have trouble seeing colors or not (to my knowledge, I have no color disability).

[Roxor128]

Maybe just making the wires a little bit thicker and having a gradient to them would make them easier to see?

The backgrounds tend to be fairly light, so maybe having the wires go from light in the middle to dark on the edges might make them stand out a bit more?

I do agree the wires can be hard to see at times. Usually green circuit wires over grass or sand or power transmission ones when passing over copper ore.