Mirrors/bevy
2
0
Fork 0
mirror of https://github.com/bevyengine/bevy synced 2024-11-24 21:53:07 +00:00
Code Issues Projects Releases Packages Wiki Activity

Gate diffuse and specular transmission behind shader defs (#11627)

Browse source 
# Objective

- Address #10338

## Solution

- When implementing specular and diffuse transmission, I inadvertently
introduced a performance regression. On high-end hardware it is barely
noticeable, but **for lower-end hardware it can be pretty brutal**. If I
understand it correctly, this is likely due to use of masking by the GPU
to implement control flow, which means that you still pay the price for
the branches you don't take;
- To avoid that, this PR introduces new shader defs (controlled via
`StandardMaterialKey`) that conditionally include the transmission
logic, that way the shader code for both types of transmission isn't
even sent to the GPU if you're not using them;
- This PR also renames ~~`STANDARDMATERIAL_NORMAL_MAP`~~ to
`STANDARD_MATERIAL_NORMAL_MAP` for consistency with the naming
convention used elsewhere in the codebase. (Drive-by fix)

---

## Changelog

- Added new shader defs, set when using transmission in the
`StandardMaterial`:
  - `STANDARD_MATERIAL_SPECULAR_TRANSMISSION`;
  - `STANDARD_MATERIAL_DIFFUSE_TRANSMISSION`;
  - `STANDARD_MATERIAL_SPECULAR_OR_DIFFUSE_TRANSMISSION`.
- Fixed performance regression caused by the introduction of
transmission, by gating transmission shader logic behind the newly
introduced shader defs;
- Renamed ~~`STANDARDMATERIAL_NORMAL_MAP`~~ to
`STANDARD_MATERIAL_NORMAL_MAP` for consistency;

## Migration Guide

- If you were using `#ifdef STANDARDMATERIAL_NORMAL_MAP` on your shader
code, make sure to update the name to `STANDARD_MATERIAL_NORMAL_MAP`;
(with an underscore between `STANDARD` and `MATERIAL`)
This commit is contained in:
Marco Buono 2024-02-02 12:01:56 -03:00 committed by GitHub
parent 0ffc8d8a6f
commit 91c467ebfc
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
5 changed files with 125 additions and 104 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
assets/shaders/array_texture.wgsl
View file

@ -43,7 +43,7 @@ fn fragment(
double_sided,
is_front,
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
#ifdef STANDARD_MATERIAL_NORMAL_MAP
mesh.world_tangent,
#endif
#endif

19
crates/bevy_pbr/src/pbr_material.rs
View file

@ -740,6 +740,8 @@ pub struct StandardMaterialKey {
cull_mode: Option<Face>,
depth_bias: i32,
relief_mapping: bool,
diffuse_transmission: bool,
specular_transmission: bool,
}
impl From<&StandardMaterial> for StandardMaterialKey {
@ -752,6 +754,8 @@ impl From<&StandardMaterial> for StandardMaterialKey {
material.parallax_mapping_method,
ParallaxMappingMethod::Relief { .. }
),
diffuse_transmission: material.diffuse_transmission > 0.0,
specular_transmission: material.specular_transmission > 0.0,
}
}
}
@ -811,11 +815,24 @@ impl Material for StandardMaterial {
let shader_defs = &mut fragment.shader_defs;
if key.bind_group_data.normal_map {
shader_defs.push("STANDARDMATERIAL_NORMAL_MAP".into());
shader_defs.push("STANDARD_MATERIAL_NORMAL_MAP".into());
}
if key.bind_group_data.relief_mapping {
shader_defs.push("RELIEF_MAPPING".into());
}
if key.bind_group_data.diffuse_transmission {
shader_defs.push("STANDARD_MATERIAL_DIFFUSE_TRANSMISSION".into());
}
if key.bind_group_data.specular_transmission {
shader_defs.push("STANDARD_MATERIAL_SPECULAR_TRANSMISSION".into());
}
if key.bind_group_data.diffuse_transmission || key.bind_group_data.specular_transmission
{
shader_defs.push("STANDARD_MATERIAL_SPECULAR_OR_DIFFUSE_TRANSMISSION".into());
}
}
descriptor.primitive.cull_mode = key.bind_group_data.cull_mode;
if let Some(label) = &mut descriptor.label {

2
crates/bevy_pbr/src/render/pbr_fragment.wgsl
View file

@ -190,7 +190,7 @@ fn pbr_input_from_standard_material(
double_sided,
is_front,
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
#ifdef STANDARD_MATERIAL_NORMAL_MAP
in.world_tangent,
#endif
#endif

48
crates/bevy_pbr/src/render/pbr_functions.wgsl
View file

@ -50,7 +50,7 @@ fn prepare_world_normal(
) -> vec3<f32> {
var output: vec3<f32> = world_normal;
#ifndef VERTEX_TANGENTS
#ifndef STANDARDMATERIAL_NORMAL_MAP
#ifndef STANDARD_MATERIAL_NORMAL_MAP
// NOTE: When NOT using normal-mapping, if looking at the back face of a double-sided
// material, the normal needs to be inverted. This is a branchless version of that.
output = (f32(!double_sided || is_front) * 2.0 - 1.0) * output;
@ -65,7 +65,7 @@ fn apply_normal_mapping(
double_sided: bool,
is_front: bool,
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
#ifdef STANDARD_MATERIAL_NORMAL_MAP
world_tangent: vec4<f32>,
#endif
#endif
@ -83,7 +83,7 @@ fn apply_normal_mapping(
var N: vec3<f32> = world_normal;
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
#ifdef STANDARD_MATERIAL_NORMAL_MAP
// NOTE: The mikktspace method of normal mapping explicitly requires that these NOT be
// normalized nor any Gram-Schmidt applied to ensure the vertex normal is orthogonal to the
// vertex tangent! Do not change this code unless you really know what you are doing.
@ -95,7 +95,7 @@ fn apply_normal_mapping(
#ifdef VERTEX_TANGENTS
#ifdef VERTEX_UVS
#ifdef STANDARDMATERIAL_NORMAL_MAP
#ifdef STANDARD_MATERIAL_NORMAL_MAP
// Nt is the tangent-space normal.
var Nt = textureSampleBias(pbr_bindings::normal_map_texture, pbr_bindings::normal_map_sampler, uv, mip_bias).rgb;
if (standard_material_flags & pbr_types::STANDARD_MATERIAL_FLAGS_TWO_COMPONENT_NORMAL_MAP) != 0u {
@ -213,7 +213,7 @@ fn apply_pbr_lighting(
let light_contrib = lighting::point_light(in.world_position.xyz, light_id, roughness, NdotV, in.N, in.V, R, F0, f_ab, diffuse_color);
direct_light += light_contrib * shadow;
if diffuse_transmission > 0.0 {
#ifdef STANDARD_MATERIAL_DIFFUSE_TRANSMISSION
// NOTE: We use the diffuse transmissive color, the second Lambertian lobe's calculated
// world position, inverted normal and view vectors, and the following simplified
// values for a fully diffuse transmitted light contribution approximation:
@ -228,9 +228,9 @@ fn apply_pbr_lighting(
&& (view_bindings::point_lights.data[light_id].flags & mesh_view_types::POINT_LIGHT_FLAGS_SHADOWS_ENABLED_BIT) != 0u) {
transmitted_shadow = shadows::fetch_point_shadow(light_id, diffuse_transmissive_lobe_world_position, -in.world_normal);
}
let light_contrib = lighting::point_light(diffuse_transmissive_lobe_world_position.xyz, light_id, 1.0, 1.0, -in.N, -in.V, vec3<f32>(0.0), vec3<f32>(0.0), vec2<f32>(0.1), diffuse_transmissive_color);
transmitted_light += light_contrib * transmitted_shadow;
}
let transmitted_light_contrib = lighting::point_light(diffuse_transmissive_lobe_world_position.xyz, light_id, 1.0, 1.0, -in.N, -in.V, vec3<f32>(0.0), vec3<f32>(0.0), vec2<f32>(0.1), diffuse_transmissive_color);
transmitted_light += transmitted_light_contrib * transmitted_shadow;
#endif
}
// Spot lights (direct)
@ -245,7 +245,7 @@ fn apply_pbr_lighting(
let light_contrib = lighting::spot_light(in.world_position.xyz, light_id, roughness, NdotV, in.N, in.V, R, F0, f_ab, diffuse_color);
direct_light += light_contrib * shadow;
if diffuse_transmission > 0.0 {
#ifdef STANDARD_MATERIAL_DIFFUSE_TRANSMISSION
// NOTE: We use the diffuse transmissive color, the second Lambertian lobe's calculated
// world position, inverted normal and view vectors, and the following simplified
// values for a fully diffuse transmitted light contribution approximation:
@ -260,9 +260,9 @@ fn apply_pbr_lighting(
&& (view_bindings::point_lights.data[light_id].flags & mesh_view_types::POINT_LIGHT_FLAGS_SHADOWS_ENABLED_BIT) != 0u) {
transmitted_shadow = shadows::fetch_spot_shadow(light_id, diffuse_transmissive_lobe_world_position, -in.world_normal);
}
let light_contrib = lighting::spot_light(diffuse_transmissive_lobe_world_position.xyz, light_id, 1.0, 1.0, -in.N, -in.V, vec3<f32>(0.0), vec3<f32>(0.0), vec2<f32>(0.1), diffuse_transmissive_color);
transmitted_light += light_contrib * transmitted_shadow;
}
let transmitted_light_contrib = lighting::spot_light(diffuse_transmissive_lobe_world_position.xyz, light_id, 1.0, 1.0, -in.N, -in.V, vec3<f32>(0.0), vec3<f32>(0.0), vec2<f32>(0.1), diffuse_transmissive_color);
transmitted_light += transmitted_light_contrib * transmitted_shadow;
#endif
}
// directional lights (direct)
@ -286,7 +286,7 @@ fn apply_pbr_lighting(
#endif
direct_light += light_contrib * shadow;
if diffuse_transmission > 0.0 {
#ifdef STANDARD_MATERIAL_DIFFUSE_TRANSMISSION
// NOTE: We use the diffuse transmissive color, the second Lambertian lobe's calculated
// world position, inverted normal and view vectors, and the following simplified
// values for a fully diffuse transmitted light contribution approximation:
@ -301,15 +301,15 @@ fn apply_pbr_lighting(
&& (view_bindings::lights.directional_lights[i].flags & mesh_view_types::DIRECTIONAL_LIGHT_FLAGS_SHADOWS_ENABLED_BIT) != 0u) {
transmitted_shadow = shadows::fetch_directional_shadow(i, diffuse_transmissive_lobe_world_position, -in.world_normal, view_z);
}
let light_contrib = lighting::directional_light(i, 1.0, 1.0, -in.N, -in.V, vec3<f32>(0.0), vec3<f32>(0.0), vec2<f32>(0.1), diffuse_transmissive_color);
transmitted_light += light_contrib * transmitted_shadow;
}
let transmitted_light_contrib = lighting::directional_light(i, 1.0, 1.0, -in.N, -in.V, vec3<f32>(0.0), vec3<f32>(0.0), vec2<f32>(0.1), diffuse_transmissive_color);
transmitted_light += transmitted_light_contrib * transmitted_shadow;
#endif
}
// Ambient light (indirect)
var indirect_light = ambient::ambient_light(in.world_position, in.N, in.V, NdotV, diffuse_color, F0, perceptual_roughness, diffuse_occlusion);
if diffuse_transmission > 0.0 {
#ifdef STANDARD_MATERIAL_DIFFUSE_TRANSMISSION
// NOTE: We use the diffuse transmissive color, the second Lambertian lobe's calculated
// world position, inverted normal and view vectors, and the following simplified
// values for a fully diffuse transmitted light contribution approximation:
@ -319,7 +319,7 @@ fn apply_pbr_lighting(
// F0 = vec3<f32>(0.0)
// diffuse_occlusion = vec3<f32>(1.0)
transmitted_light += ambient::ambient_light(diffuse_transmissive_lobe_world_position, -in.N, -in.V, 1.0, diffuse_transmissive_color, vec3<f32>(0.0), 1.0, vec3<f32>(1.0));
}
#endif
// Environment map light (indirect)
#ifdef ENVIRONMENT_MAP
@ -339,7 +339,7 @@ fn apply_pbr_lighting(
// light in the call to `specular_transmissive_light()` below
var specular_transmitted_environment_light = vec3<f32>(0.0);
if diffuse_transmission > 0.0 || specular_transmission > 0.0 {
#ifdef STANDARD_MATERIAL_SPECULAR_OR_DIFFUSE_TRANSMISSION
// NOTE: We use the diffuse transmissive color, inverted normal and view vectors,
// and the following simplified values for the transmitted environment light contribution
// approximation:
@ -368,9 +368,13 @@ fn apply_pbr_lighting(
T,
vec3<f32>(1.0),
in.world_position.xyz);
#ifdef STANDARD_MATERIAL_DIFFUSE_TRANSMISSION
transmitted_light += transmitted_environment_light.diffuse * diffuse_transmissive_color;
#endif
#ifdef STANDARD_MATERIAL_SPECULAR_TRANSMISSION
specular_transmitted_environment_light = transmitted_environment_light.specular * specular_transmissive_color;
}
#endif
#endif // STANDARD_MATERIAL_SPECULAR_OR_DIFFUSE_TRANSMISSION
#else
// If there's no environment map light, there's no transmitted environment
// light specular component, so we can just hardcode it to zero.
@ -383,9 +387,8 @@ fn apply_pbr_lighting(
let emissive_light = emissive.rgb * output_color.a;
if specular_transmission > 0.0 {
#ifdef STANDARD_MATERIAL_SPECULAR_TRANSMISSION
transmitted_light += transmission::specular_transmissive_light(in.world_position, in.frag_coord.xyz, view_z, in.N, in.V, F0, ior, thickness, perceptual_roughness, specular_transmissive_color, specular_transmitted_environment_light).rgb;
}
if (in.material.flags & pbr_types::STANDARD_MATERIAL_FLAGS_ATTENUATION_ENABLED_BIT) != 0u {
// We reuse the `atmospheric_fog()` function here, as it's fundamentally
@ -401,6 +404,7 @@ fn apply_pbr_lighting(
vec3<f32>(0.0) // TODO: Pass in (pre-attenuated) scattered light contribution here
).rgb;
}
#endif
// Total light
output_color = vec4<f32>(

4
crates/bevy_pbr/src/render/pbr_prepass.wgsl
View file

@ -38,9 +38,9 @@ fn fragment(
double_sided,
is_front,
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
#ifdef STANDARD_MATERIAL_NORMAL_MAP
in.world_tangent,
#endif // STANDARDMATERIAL_NORMAL_MAP
#endif // STANDARD_MATERIAL_NORMAL_MAP
#endif // VERTEX_TANGENTS
#ifdef VERTEX_UVS
in.uv,