Question by nanomoney · Mar 28 at 09:02 AM · shader transparent order

Transparent objects change render order depending on the camera angle

Hi,

Both objects use Transparent Material. It looks like it's in front of you depending on the angle. But why does the rendering result of the object behind come out differently depending on the angle?

alt text

Thanks!

untitle.png (447.6 kB)

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andrew-lukasik · Mar 28 at 09:33 AM 1

This is because objects are sorted for rendering order:

by their volume ( AABB to be exact i.e. "Axis Aligned Bounding Box")
by pixel depth

Transparent shaders do not write to (pixel) depth buffer, hence #2 wont help in proper sorting. So, what the renderer is left with here is AABBs to guesstimate the sorting order with. This results in sorting, more or less, by mesh distance to camera.

this applies to every 3d engine out there

To fix this, change box's shader to opaque one.

nanomoney · Mar 29 at 01:54 AM 0

Thank you for your answer.

I want to use the box in the back as a Transparent Material, but is there no way?

andrew-lukasik nanomoney · Mar 29 at 08:11 AM 0

Opaque shaders allow for "cutout" / "alpha clipping" (binary pixel visibility), it's solves sorting issue, but not sure this is the kind of transparency you are after for this box here.