Problem with z order when combining sprites and 3D meshes

Unity Engine
1

Hiya all,

I’m trying to combine sprites with 3D meshes and I want to enjoy z-ordering between them. Unity seems to support it perfectly (eg sprite behaves like a standing quad, exactly like I wanted), however I’m struggling with making the sprites always face the camera while z-ordering with meshes.

You see, what happens is that the sprite quad is rotated toward the camera, which is high in the sky it, and it makes the upper part of the sprite go into the mesh and get hidden by it. I added a screencap to illustrate the problem better:

2657896--187404--problem_explained.jpg
2657896--187404--problem_explained.jpg612×759 94 KB

Now I know I could use sorting layers etc, but I don’t want the sprite to always be in front of the mesh, I want it to behave normally.

Any ideas how can I achieve that?

Thanks!

2

Solved it myself.
I wrote a custom sprites shader and added some bonus to the out vertex Z to make up for the facing-camera angle (so all sprites get extra z over 3d meshes).

looks something like this:

v2f OUT;
        OUT.vertex = mul(UNITY_MATRIX_MVP, IN.vertex);
        OUT.vertex.z -= 0.025f;  // <-- this gives all sprites some priority over 3d meshes, to make up for the angle due to facing camera!
        OUT.texcoord = IN.texcoord;
        OUT.color = IN.color * _Color;

Note that the correct way to do it would be using the Offset property, but for some reason that just didn’t work :confused: So I made this hack and will solve the Offset thing later (later = never :P)