bevy/assets/shaders/array_texture.wgsl
robtfm 979c4094d4
pbr shader cleanup (#10105)
# Objective

cleanup some pbr shader code. improve shader stage io consistency and
make pbr.wgsl (probably many people's first foray into bevy shader code)
a little more human-readable. also fix a couple of small issues with
deferred rendering.

## Solution

mesh_vertex_output: 
- rename to forward_io (to align with prepass_io)
- rename `MeshVertexOutput` to `VertexOutput` (to align with prepass_io)
- move `Vertex` from mesh.wgsl into here (to align with prepass_io)

prepass_io: 
- remove `FragmentInput`, use `VertexOutput` directly (to align with
forward_io)
- rename `VertexOutput::clip_position` to `position` (to align with
forward_io)

pbr.wgsl:
- restructure so we don't need `#ifdefs` on the actual entrypoint, use
VertexOutput and FragmentOutput in all cases and use #ifdefs to import
the right struct definitions.
- rearrange to make the flow clearer
- move alpha_discard up from `pbr_functions::pbr` to avoid needing to
call it on some branches and not others
- add a bunch of comments

deferred_lighting:
- move ssao into the `!unlit` block to reflect forward behaviour
correctly
- fix compile error with deferred + premultiply_alpha

## Migration Guide

in custom material shaders:
- `pbr_functions::pbr` no longer calls to
`pbr_functions::alpha_discard`. if you were using the `pbr` function in
a custom shader with alpha mask mode you now also need to call
alpha_discard manually
- rename imports of `bevy_pbr::mesh_vertex_output` to
`bevy_pbr::forward_io`
- rename instances of `MeshVertexOutput` to `VertexOutput`

in custom material prepass shaders:
- rename instances of `VertexOutput::clip_position` to
`VertexOutput::position`
2023-10-13 19:12:40 +00:00

51 lines
1.7 KiB
WebGPU Shading Language

#import bevy_pbr::forward_io VertexOutput
#import bevy_pbr::mesh_view_bindings view
#import bevy_pbr::pbr_types STANDARD_MATERIAL_FLAGS_DOUBLE_SIDED_BIT, PbrInput, pbr_input_new
#import bevy_core_pipeline::tonemapping tone_mapping
#import bevy_pbr::pbr_functions as fns
@group(1) @binding(0) var my_array_texture: texture_2d_array<f32>;
@group(1) @binding(1) var my_array_texture_sampler: sampler;
@fragment
fn fragment(
@builtin(front_facing) is_front: bool,
mesh: VertexOutput,
) -> @location(0) vec4<f32> {
let layer = i32(mesh.world_position.x) & 0x3;
// Prepare a 'processed' StandardMaterial by sampling all textures to resolve
// the material members
var pbr_input: PbrInput = pbr_input_new();
pbr_input.material.base_color = textureSample(my_array_texture, my_array_texture_sampler, mesh.uv, layer);
#ifdef VERTEX_COLORS
pbr_input.material.base_color = pbr_input.material.base_color * mesh.color;
#endif
pbr_input.frag_coord = mesh.position;
pbr_input.world_position = mesh.world_position;
pbr_input.world_normal = fns::prepare_world_normal(
mesh.world_normal,
(pbr_input.material.flags & STANDARD_MATERIAL_FLAGS_DOUBLE_SIDED_BIT) != 0u,
is_front,
);
pbr_input.is_orthographic = view.projection[3].w == 1.0;
pbr_input.N = fns::apply_normal_mapping(
pbr_input.material.flags,
mesh.world_normal,
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
mesh.world_tangent,
#endif
#endif
mesh.uv,
view.mip_bias,
);
pbr_input.V = fns::calculate_view(mesh.world_position, pbr_input.is_orthographic);
return tone_mapping(fns::pbr(pbr_input), view.color_grading);
}