Transmission cleanup

crates/bevy_pbr/src/material.rs

@@ -645,25 +645,6 @@ pub const fn tonemapping_pipeline_key(tonemapping: Tonemapping) -> MeshPipelineK
     }
 }
 
-pub const fn screen_space_specular_transmission_pipeline_key(
-    screen_space_transmissive_blur_quality: ScreenSpaceTransmissionQuality,
-) -> MeshPipelineKey {
-    match screen_space_transmissive_blur_quality {
-        ScreenSpaceTransmissionQuality::Low => {
-            MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_LOW
-        }
-        ScreenSpaceTransmissionQuality::Medium => {
-            MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_MEDIUM
-        }
-        ScreenSpaceTransmissionQuality::High => {
-            MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_HIGH
-        }
-        ScreenSpaceTransmissionQuality::Ultra => {
-            MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_ULTRA
-        }
-    }
-}
-
 /// A system that ensures that
 /// [`crate::render::mesh::extract_meshes_for_gpu_building`] re-extracts meshes
 /// whose materials changed.

crates/bevy_pbr/src/pbr_material.rs

@@ -258,10 +258,10 @@ pub struct StandardMaterial {
     /// Specular transmission is implemented as a relatively expensive screen-space effect that allows occluded objects to be seen through the material,
     /// with distortion and blur effects.
     ///
-    /// - [`crate::ScreenSpaceTransmission::screen_space_specular_transmission_steps`] can be used to enable transmissive objects
+    /// - [`crate::ScreenSpaceTransmission::steps`] can be used to enable transmissive objects
     ///   to be seen through other transmissive objects, at the cost of additional draw calls and texture copies; (Use with caution!)
     ///   - If a simplified approximation of specular transmission using only environment map lighting is sufficient, consider setting
-    ///     [`crate::ScreenSpaceTransmission::screen_space_specular_transmission_steps`] to `0`.
+    ///     [`crate::ScreenSpaceTransmission::steps`] to `0`.
     /// - If purely diffuse light transmission is needed, (i.e. “translucency”) consider using [`StandardMaterial::diffuse_transmission`] instead,
     ///   for a much less expensive effect.
     /// - Specular transmission is rendered before alpha blending, so any material with [`AlphaMode::Blend`], [`AlphaMode::Premultiplied`], [`AlphaMode::Add`] or [`AlphaMode::Multiply`]

crates/bevy_pbr/src/render/mesh.rs

@@ -440,9 +440,7 @@ pub fn check_views_need_specialization(
             view_key |= MeshPipelineKey::DISTANCE_FOG;
         }
         if let Some(transmission) = transmission {
-            view_key |= screen_space_specular_transmission_pipeline_key(
-                transmission.screen_space_specular_transmission_quality,
-            );
+            view_key |= transmission.quality.pipeline_key();
         }
         if !view_key_cache
             .get_mut(&view.retained_view_entity)

crates/bevy_pbr/src/transmission/mod.rs

@@ -22,7 +22,7 @@ pub use texture::ViewTransmissionTexture;
 
 use texture::prepare_core_3d_transmission_textures;
 
-use crate::DrawMaterial;
+use crate::{DrawMaterial, MeshPipelineKey};
 
 /// Enables screen-space transmission for cameras.
 pub struct ScreenSpaceTransmissionPlugin;
@@ -82,21 +82,21 @@ pub struct ScreenSpaceTransmission {
     ///   to still have the environment map show up in your refractions, you can set the clear color's alpha to `0.0`.
     ///   Keep in mind that depending on the platform and your window settings, this may cause the window to become
     ///   transparent.
-    pub screen_space_specular_transmission_steps: usize,
+    pub steps: usize,
     /// The quality of the screen space specular transmission blur effect, applied to whatever's behind transmissive
     /// objects when their `roughness` is greater than `0.0`.
     ///
     /// Higher qualities are more GPU-intensive.
     ///
     /// **Note:** You can get better-looking results at any quality level by enabling TAA. See: `TemporalAntiAliasPlugin`
-    pub screen_space_specular_transmission_quality: ScreenSpaceTransmissionQuality,
+    pub quality: ScreenSpaceTransmissionQuality,
 }
 
 impl Default for ScreenSpaceTransmission {
     fn default() -> Self {
         Self {
-            screen_space_specular_transmission_steps: 1,
-            screen_space_specular_transmission_quality: Default::default(),
+            steps: 1,
+            quality: Default::default(),
         }
     }
 }
@@ -131,3 +131,22 @@ pub enum ScreenSpaceTransmissionQuality {
     /// `num_taps` = 32
     Ultra,
 }
+
+impl ScreenSpaceTransmissionQuality {
+    pub const fn pipeline_key(self) -> MeshPipelineKey {
+        match self {
+            ScreenSpaceTransmissionQuality::Low => {
+                MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_LOW
+            }
+            ScreenSpaceTransmissionQuality::Medium => {
+                MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_MEDIUM
+            }
+            ScreenSpaceTransmissionQuality::High => {
+                MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_HIGH
+            }
+            ScreenSpaceTransmissionQuality::Ultra => {
+                MeshPipelineKey::SCREEN_SPACE_SPECULAR_TRANSMISSION_ULTRA
+            }
+        }
+    }
+}

crates/bevy_pbr/src/transmission/node.rs

@@ -67,18 +67,14 @@ pub fn main_transmissive_pass_3d(
     };
 
     if !transmissive_phase.items.is_empty() {
-        let screen_space_specular_transmission_steps =
-            transmission_settings.screen_space_specular_transmission_steps;
-        if screen_space_specular_transmission_steps > 0 {
+        let steps = transmission_settings.steps;
+        if steps > 0 {
             let transmission =
                 transmission.expect("`ViewTransmissionTexture` should exist at this point");
 
-            // `transmissive_phase.items` are depth sorted, so we split them into N = `screen_space_specular_transmission_steps`
+            // `transmissive_phase.items` are depth sorted, so we split them into N = `steps`
             // ranges, rendering them back-to-front in multiple steps, allowing multiple levels of transparency.
-            for range in split_range(
-                0..transmissive_phase.items.len(),
-                screen_space_specular_transmission_steps,
-            ) {
+            for range in split_range(0..transmissive_phase.items.len(), steps) {
                 // Copy the main texture to the transmission texture
                 ctx.command_encoder().copy_texture_to_texture(
                     target.main_texture().as_image_copy(),

crates/bevy_pbr/src/transmission/phase.rs

@@ -33,7 +33,7 @@ pub struct Transmissive3d {
 
 impl PhaseItem for Transmissive3d {
     /// For now, automatic batching is disabled for transmissive items because their rendering is
-    /// split into multiple steps depending on [`crate::ScreenSpaceTransmission::screen_space_specular_transmission_steps`],
+    /// split into multiple steps depending on [`crate::ScreenSpaceTransmission::steps`],
     /// which the batching system doesn't currently know about.
     ///
     /// Having batching enabled would cause the same item to be drawn multiple times across different

crates/bevy_pbr/src/transmission/texture.rs

@@ -61,7 +61,7 @@ pub fn prepare_core_3d_transmission_textures(
         };
 
         // Don't prepare a transmission texture if the number of steps is set to 0
-        if transmission.screen_space_specular_transmission_steps == 0 {
+        if transmission.steps == 0 {
             continue;
         }
 

crates/bevy_pbr/src/transmission/transmission.wgsl

@@ -98,7 +98,7 @@ fn fetch_transmissive_background(offset_position: vec2<f32>, frag_coord: vec3<f3
     let blur_intensity = (perceptual_roughness * perceptual_roughness) / view_z;
 
 #ifdef SCREEN_SPACE_SPECULAR_TRANSMISSION_BLUR_TAPS
-    let num_taps = #{SCREEN_SPACE_SPECULAR_TRANSMISSION_BLUR_TAPS}; // Controlled by the `Camera3d::screen_space_specular_transmission_quality` property
+    let num_taps = #{SCREEN_SPACE_SPECULAR_TRANSMISSION_BLUR_TAPS}; // Controlled by the `ScreenSpaceTransmission::quality` property
 #else
     let num_taps = 8; // Fallback to 8 taps, if not specified
 #endif

examples/3d/transmission.rs

@@ -489,36 +489,28 @@ fn example_control_system(
         }
     }
 
-    if input.just_pressed(KeyCode::KeyO)
-        && transmission.screen_space_specular_transmission_steps > 0
-    {
-        transmission.screen_space_specular_transmission_steps -= 1;
+    if input.just_pressed(KeyCode::KeyO) && transmission.steps > 0 {
+        transmission.steps -= 1;
     }
 
-    if input.just_pressed(KeyCode::KeyP)
-        && transmission.screen_space_specular_transmission_steps < 4
-    {
-        transmission.screen_space_specular_transmission_steps += 1;
+    if input.just_pressed(KeyCode::KeyP) && transmission.steps < 4 {
+        transmission.steps += 1;
     }
 
     if input.just_pressed(KeyCode::KeyJ) {
-        transmission.screen_space_specular_transmission_quality =
-            ScreenSpaceTransmissionQuality::Low;
+        transmission.quality = ScreenSpaceTransmissionQuality::Low;
     }
 
     if input.just_pressed(KeyCode::KeyK) {
-        transmission.screen_space_specular_transmission_quality =
-            ScreenSpaceTransmissionQuality::Medium;
+        transmission.quality = ScreenSpaceTransmissionQuality::Medium;
     }
 
     if input.just_pressed(KeyCode::KeyL) {
-        transmission.screen_space_specular_transmission_quality =
-            ScreenSpaceTransmissionQuality::High;
+        transmission.quality = ScreenSpaceTransmissionQuality::High;
     }
 
     if input.just_pressed(KeyCode::Semicolon) {
-        transmission.screen_space_specular_transmission_quality =
-            ScreenSpaceTransmissionQuality::Ultra;
+        transmission.quality = ScreenSpaceTransmissionQuality::Ultra;
     }
 
     let rotation = if input.pressed(KeyCode::ArrowRight) {
@@ -565,8 +557,8 @@ fn example_control_system(
             "             D  Depth Prepass: {}\n",
             "             T  TAA: {}\n",
         ),
-        transmission.screen_space_specular_transmission_quality,
-        transmission.screen_space_specular_transmission_steps,
+        transmission.quality,
+        transmission.steps,
         state.diffuse_transmission,
         state.specular_transmission,
         state.thickness,

examples/large_scenes/bistro/src/main.rs

@@ -262,8 +262,8 @@ pub fn setup(mut commands: Commands, asset_server: Res<AssetServer>, args: Res<A
         Msaa::Off,
         Camera3d::default(),
         ScreenSpaceTransmission {
-            screen_space_specular_transmission_steps: 0,
-            screen_space_specular_transmission_quality: ScreenSpaceTransmissionQuality::Low,
+            steps: 0,
+            quality: ScreenSpaceTransmissionQuality::Low,
         },
         Hdr,
         Transform::from_xyz(-10.5, 1.7, -1.0).looking_at(Vec3::new(0.0, 3.5, 0.0), Vec3::Y),

release-content/migration-guides/transmission.md

@@ -1,9 +1,9 @@
 ---
 title: "Transmission has been moved to `bevy_pbr`"
-pull_requests: [22687, 22706]
+pull_requests: [22687, 22706, 22763]
 ---
 
-`Camera3d::screen_space_specular_transmission_steps` and `Camera3d::screen_space_specular_transmission_quality` have been pulled out into a separate component, `ScreenSpaceTransmission`, and put in `bevy_pbr`.
+`Camera3d::screen_space_specular_transmission_steps` and `Camera3d::screen_space_specular_transmission_quality` have been pulled out into a separate component, `ScreenSpaceTransmission`, and put in `bevy_pbr`. The field names have been shortened to `steps` and `quality`.
 
 `ScreenSpaceTransmissionQuality` has been moved from `bevy_camera` to `bevy_pbr`.
 
@@ -12,3 +12,5 @@ pull_requests: [22687, 22706]
 `ViewTransmissionTexture` and `Transmissive3d` has been moved from `bevy_core_pipelines` to `bevy_pbr`.
 
 `Node3d::MainTransmissivePass` is now initialized by `PbrPlugin`.
+
+`screen_space_specular_transmission_pipeline_key` has become `ScreenSpaceTransmissionQuality::pipeline_key`.