Z-index issues

Questions & Answers
1

Update 4 - Solution/Workaround

It seems like this issue occurs when you have multiple objects with the Transparent shaders. In my case - the player and the column. When I changed the shader of the column to Transparent/Cutout the problem disappeared. The drawback is that now the column has jagged edges, but I think it’s much better than jagged edges on the player, since he’s animated.

I hope this helps anyone.

Update 3

It seems like this is a known limitation of the Transparent shader. From the Unity docs:

Transparent Cutout Properties

Cutout shader is an alternative way of displaying transparent objects. Differences between Cutout and regular Transparent shaders are:

  • This shader cannot have partially transparent areas. Everything will be either fully opaque or fully transparent.
  • Objects using this shader can cast and receive shadows!
  • The graphical sorting problems normally associated with Transparent shaders do not occur when using this shader.

Link: Unity - Manual: Transparent Cutout Bumped Specular

Update 2

When I switch to the Transparent/Cutout/Diffuse shader the Z-index problem is gone and I have transparency, but also jagged edges around my sprite. What can I do about those jagged edges?

Update 1

I’m using a Transparent/Diffuse material for the player’s plane. When I change it to just Diffuse, the Z-index problem is gone, but the transparency is gone.

Question

I’m getting this weird issue - see the shot below. You can clearly see that the character plane is in front of the column, but the column gets rendered in front of it. I have tried searching for similar issues, they are all about Z fighting, which I understand is something different.

So as you can see there is plenty of space between the planes. A couple of things to note:

  • the column is using a billboarding script, which rotates it on the Y axis towards the camera. Turning off the script makes no difference.
  • I tried playing with the camera. Changing the clip planes makes no difference. The only think that sort of fixed it is when I got the camera super close to the plane with a really wide viewing angle. Obviously, that’s not an option :slight_smile:
  • the character can walk next to the wall (on the left of the screenshot) without any z-index issues and the planes even intersect.

Any ideas?

16890-untitled-1.jpg
16890-untitled-1.jpg788×733 131 KB

Here is the hierarchy in the scene as well as all affected objects’ positions at the time of the glitch.

16901-untitled-2.jpg
16901-untitled-2.jpg1368×776 203 KB

2

It seems like this is a known limitation of the Transparent shader. From the Unity docs:

Transparent Cutout Properties

Cutout shader is an alternative way of displaying transparent objects. Differences between Cutout and regular Transparent shaders are:

  • This shader cannot have partially transparent areas. Everything will be either fully opaque or fully transparent.
  • Objects using this shader can cast and receive shadows!
  • The graphical sorting problems normally associated with Transparent shaders do not occur when using this shader.

Link: Unity - Manual: Transparent Cutout Bumped Specular

This issue occurs when you have multiple objects with the Transparent shaders. In my case - the player and the column. When I changed the shader of the column to Transparent/Cutout the problem disappeared. The drawback is that now the column has jagged edges, but I think it’s much better than jagged edges on the player, since he’s animated.

I hope this helps anyone.

3

Under the SubShader section, add +1 to the item in the “Queue” section. For me, this became “Queue” = “Transparent+1”.

	SubShader
	{
	Tags{"Queue" = "Transparent+1"}
		Cull Off ZWrite Off ZTest Always