Hiya everyone, what is with unity's default shadow attenuation causing artefacting like this on surfaces? This is even present on the default lit shaders...
#Default Unity Shadows causing artefacts
glossy pivot
steady turtle
That's a common shadowmapping artefact. Try playing the shadow settings, like normal bias and such.
glossy pivot
I have, unfortunantly didnt change much, I'm using my own HLSL shader that samples mainlight.shadowattenuation
it's a toon shader so these artefacts are pretty visible
steady turtle
I have, unfortunantly didnt change much, I'm using my own HLSL shader that sampl...
Normal or depth bias should have at least some effect then. If it doesn't, then perhaps you're modifying settings that are not actually used in rendering currently.
glossy pivot
This is found within the URP settings right?
steady turtle
Yes.
Make sure you're modifying the currently used urp asset.
By default there are several for different quality settings.
glossy pivot
Okay I found the right one, still no effect when I play around with depth and normal bias
Same artefacting
steady turtle
No change at all?
glossy pivot
no change
steady turtle
What do you have assigned in the active quality settings?
glossy pivot
Ultra, the other shadow settings do work like Max Distance and such
so it is the correct asset that is rendering
But the depth/normals bias doesnt want to work unfortunantely
steady turtle
Hmm... Try a standard(urp lit?) shader and see if the setting has effect on it.
glossy pivot
Well rather, it does work, just doesnt stop the artefacting on the surfaces that matter
glossy pivot
Hmm... Try a standard(urp lit?) shader and see if the setting has effect on it.
It does
it's less visible
but still is there
steady turtle
Well rather, it does work, just doesnt stop the artefacting on the surfaces that...
That's an important distinction.
glossy pivot
I'm wondering if this is something to blame unity's lighting system for, or rather my HLSL shader
steady turtle
The artefact is basically caused by a floating point error, so reducing your shadow distance might help.
glossy pivot
I have
steady turtle
Can you share your shadow settings?
glossy pivot
it's reduced by quite a bit
This is my shadow code
It self shadows with a dot product and also uses mainlight.shadowattenuation
ShadowCull is just culling the shadow attenuation smoothly
steady turtle
Does adding more cascades fix the issue a bit?
glossy pivot
Does adding more cascades fix the issue a bit?
It does but it causes another issue that's even worse
steady turtle
It might be.
I'd start from getting issue solved with the urp lit shader first. This way you can eliminate the shader issue factor.
steady turtle
It does but it causes another issue that's even worse
What issue?
steady turtle
Does this happen with urp lit?
glossy pivot
no... must be my shader then
steady turtle
Yep. So for shadow acne - > more cascades.
For switching between cascades - > investigate your shader.
glossy pivot
Are more cascades going to be less performant on low hardware?
glossy pivot
Yep. So for shadow acne - > more cascades.
For switching between cascades - > i...
Do you know how I'd implement switching between shadow cascades on a shader like mine?
steady turtle
Do you know how I'd implement switching between shadow cascades on a shader like...
Not out of the top of my head.
I'd look at the urp lit shadow implementation to see if you're missing something.
glossy pivot
Do you have a link to the code for that?
steady turtle
There's on github, but you call also open it in the package cache in your library folder. Just open the shader dirs with vs code or something and search through it.
Can also go to the urp lit shader code from the inspector.
One extra thing to try is to see if this issue is caused by the directional or point lights(try commenting out either). This would give some more clues as to what the cause is.
Commenting out any other logic might also help to isolate the issue.
glossy pivot
there are no point lights in the scene, just the main directional light
steady turtle
Indeed, but that doesn't mean there's no bug in that logic.
glossy pivot
Sorry I'm still trying to find the lit shader code
steady turtle
50% of debugging shaders is understanding what line causes the issue.
glossy pivot
I haven't written the shader to incorporate point lights into its shadow and light calculation
just the mainlight.direction
steady turtle
Sorry I'm still trying to find the lit shader code
Open your project libraty/psckagecache/universal
There should be shader and shader include directories. The shader source code is somewhere there.
glossy pivot
I found a shader called lit
sounds about right
in universal render pipeline folder
steady turtle
I haven't written the shader to incorporate point lights into its shadow and lig...
One thing to try is to output the shadowAttenuation(and after that you shadow product) directly as the final color and see if the issue persists. That would eliminate any other culprits.
glossy pivot
Yep, I isolated the shadow attenuation result and it's that causing the artefacts
and the shadow cascading issue
steady turtle
Great, then looking at the unity implementation might provide some clues.
glossy pivot
It's important to note that I'm trying to make a toon shader
Not a default lit shader
I've got most of the toon stuff down
it's just shadow attenuation...
steady turtle
I get it, but applying shadows should be almost the same as in pbr.
glossy pivot
I'm looking through the lit shader, can't seem to find anything inparticular about shadow attenuation
steady turtle
It's likely gonna be in some include file. Gotta dig through the includes/macros, function calls.
glossy pivot
just seems to call a bunch of pragmas and includes and then ends
steady turtle
there should be a pragma specifying the fragment shader name. And the definition should be in one of the includes.
If you have github copilot or any other coding agent/assistant, asking it to navigate to where the shadow attenuation is applied should make it easy to find.
glossy pivot
I'm sorry to be such a pain
I haven't been doing HLSL for very long
This is all new to me
Deepseek seems to suggest it's in lighting.hlsl so I'm looking there
steady turtle
Yeah, actually, now that I think about it, you seem to mix up lighting calculations with shadows.🤔
glossy pivot
My apologies
I've been using shader-graph for a long time
I'm trying to move onto HLSL for more control
I'm getting closer to the solution though, it seems I just need to make it so shadow cascading works on my shader
glossy pivot
I may have solved it
@steady turtle
It was not what either of us anticipated
I think it was actually my shadow caster
The self casted attenuation was fucked I think... but gimme a moment to confirm
Yeah it was that
Lmao
looks far closer now to what I wanted
Thank you for your help Dlich! I think I've seen you here the past few times I had shader issues, I am thankful for your help and way of explaining stuff.
I've made it a goal for myself over the next year to get into HLSL so I'm better prepared for working around in-house engines as I take more contracts from local studios
steady turtle
Thank you for your help Dlich! I think I've seen you here the past few times I h...
Wasn't very helpful this time, but you're welcome.