Can not use Light shadow When I use a wgsl to render?

[ashen island]

I use wgsl for my mesh. when i what to use DirectionalLight shadows_enabled: true, just get a error:

Caused by:
    In Device::create_render_pipeline
      note: label = `prepass_pipeline`
    error matching VERTEX shader requirements against the pipeline
    location[1] Float32x2 interpolated as Some(Perspective) with sampling Some(Center) is not provided by the previous stage outputs
    input type is not compatible with the provided Uint32

How can i fix it.
code it in https://github.com/zzhgithub/just_join

[twin plover]

I think maybe it's that the shadows use the prepass vertex shader, and the default prepass vertex shader has the uvs (Float32x2) at location 1
https://github.com/bevyengine/bevy/blob/v0.10.1/crates/bevy_pbr/src/prepass/mod.rs#L261

You can override the prepass vertex shader if you'd like:
https://github.com/bevyengine/bevy/blob/v0.10.1/crates/bevy_pbr/src/material.rs

I've used this to get wireframes to always render in front: #rendering message
May or may not be a suitable solution in this case depending on what you are looking for.
It would go in the fn specialize() for your wireframe material

[ashen island]

Thank you I will try.

[twin plover]

Oh sorry, just realized I meant this as a comment on your other question.

[ashen island]

lol I git it .

I change the UVS location. there is no error happen. but i also not see shadow. Why?

[twin plover]

try:
pbr_input.flags |= MESH_FLAGS_SHADOW_RECEIVER_BIT;
here:
https://github.com/zzhgithub/just_join/blob/main/assets/shaders/mesh_render.wgsl#L108
assuming this is the shader in question

The const is in mesh_types, which I think is brought in by mesh_bindings which you already include.
https://github.com/bevyengine/bevy/blob/v0.10.1/crates/bevy_pbr/src/render/mesh_types.wgsl
https://github.com/bevyengine/bevy/blob/v0.10.1/crates/bevy_pbr/src/render/mesh_bindings.wgsl

[ashen island]

fix it

Thank you

and a addtional question why Slow reflection is not realistic. The shaded part is too dark to have floodlight.

[twin plover]

are you referring the bit of light here?

[ashen island]

yes

Your understanding is too strong

[twin plover]

I think that's from the AmbientLight

Without raytracing or other methods the renderer can't know what is occluded from ambient light

This is probably the specular component (rough reflection)

[ashen island]

OK I will try

[twin plover]

You can turn down the ambient light if you'd like

it's a resource

[ashen island]

try to add prb_input params?

[twin plover]

App::new()
    .insert_resource(AmbientLight {
        color: Color::WHITE,
        brightness: 0.0,
    })

[ashen island]

I use DirectionalLight it that mater?

ok

Wait my try

should I change the brightness ?

[twin plover]

It's up to you

I would probably keep a little bit

you could maybe also use another directional light but shadowless pointing from the top down, not straight down, but opposite your other directional light

Then you'll get some light in the shadows but not when looking at low grazing angles

You could also play with environment maps like shown here:
https://github.com/bevyengine/bevy/blob/v0.10.1/examples/3d/load_gltf.rs#L31

I think you might be able to use something like
https://github.com/pcwalton/gltf-ibl-sampler-egui
with
https://polyhaven.com/hdris

This can act as a replacement of the ambient light.