StandardMaterial flat values (#3)

StandardMaterial flat values

crates/bevy_ecs/src/system/commands/mod.rs

@@ -59,9 +59,7 @@ impl<'a> Commands<'a> {
     }
 
     pub fn get_or_spawn(&mut self, entity: Entity) -> EntityCommands<'a, '_> {
-        self.add(GetOrSpawn {
-            entity,
-        });
+        self.add(GetOrSpawn { entity });
         EntityCommands {
             entity,
             commands: self,
@@ -292,8 +290,7 @@ pub struct GetOrSpawn {
     entity: Entity,
 }
 
-impl Command for GetOrSpawn
-{
+impl Command for GetOrSpawn {
     fn write(self: Box<Self>, world: &mut World) {
         world.get_or_spawn(self.entity);
     }

crates/bevy_ecs/src/system/exclusive_system.rs

@@ -1,4 +1,8 @@
-use crate::{archetype::ArchetypeGeneration, system::{check_system_change_tick, BoxedSystem, IntoSystem, System, SystemId}, world::World};
+use crate::{
+    archetype::ArchetypeGeneration,
+    system::{check_system_change_tick, BoxedSystem, IntoSystem, System, SystemId},
+    world::World,
+};
 use std::borrow::Cow;
 
 pub trait ExclusiveSystem: Send + Sync + 'static {

crates/bevy_ecs/src/world/mod.rs

@@ -100,7 +100,6 @@ impl World {
         &mut self.entities
     }
 
-
     /// Retrieves this world's [Archetypes] collection
     #[inline]
     pub fn archetypes(&self) -> &Archetypes {

crates/crevice/src/lib.rs

@@ -139,4 +139,4 @@ pub mod internal;
 
 mod mint;
 
-mod glam;
+mod glam;

examples/3d/3d_scene_pipelined.rs

@@ -37,23 +37,39 @@ fn setup(
     // plane
     commands.spawn_bundle(PbrBundle {
         mesh: meshes.add(Mesh::from(shape::Plane { size: 5.0 })),
-        material: materials.add(Color::rgb(0.3, 0.5, 0.3).into()),
+        material: materials.add(StandardMaterial {
+            color: Color::INDIGO,
+            roughness: 1.0,
+            ..Default::default()
+        }),
         ..Default::default()
     });
     // cube
     commands
         .spawn_bundle(PbrBundle {
             mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
-            material: materials.add(Color::rgb(0.8, 0.7, 0.6).into()),
+            material: materials.add(StandardMaterial {
+                color: Color::PINK,
+                roughness: 0.0,
+                metallic: 1.0,
+                reflectance: 1.0,
+                ..Default::default()
+            }),
             transform: Transform::from_xyz(0.0, 1.0, 0.0),
             ..Default::default()
         })
         .insert(Movable);
     // sphere
     commands
         .spawn_bundle(PbrBundle {
-            mesh: meshes.add(Mesh::from(shape::UVSphere { radius: 0.5, ..Default::default() })),
-            material: materials.add(Color::rgb(0.8, 0.7, 0.6).into()),
+            mesh: meshes.add(Mesh::from(shape::UVSphere {
+                radius: 0.5,
+                ..Default::default()
+            })),
+            material: materials.add(StandardMaterial {
+                color: Color::LIME_GREEN,
+                ..Default::default()
+            }),
             transform: Transform::from_xyz(1.5, 1.0, 1.5),
             ..Default::default()
         })

pipelined/bevy_pbr2/src/lib.rs

@@ -9,7 +9,6 @@ pub use material::*;
 pub use render::*;
 
 use bevy_app::prelude::*;
-use bevy_asset::AddAsset;
 use bevy_ecs::prelude::*;
 use bevy_render2::{
     core_pipeline,
@@ -29,7 +28,7 @@ pub struct PbrPlugin;
 
 impl Plugin for PbrPlugin {
     fn build(&self, app: &mut App) {
-        app.add_asset::<StandardMaterial>();
+        app.add_plugin(StandardMaterialPlugin);
 
         let render_app = app.sub_app_mut(0);
         render_app
@@ -50,6 +49,7 @@ impl Plugin for PbrPlugin {
             .add_system_to_stage(RenderStage::Cleanup, render::cleanup_view_lights.system())
             .init_resource::<PbrShaders>()
             .init_resource::<ShadowShaders>()
+            .init_resource::<MaterialMeta>()
             .init_resource::<MeshMeta>()
             .init_resource::<LightMeta>();
 

pipelined/bevy_pbr2/src/material.rs

@@ -1,10 +1,71 @@
-use bevy_reflect::{Reflect, TypeUuid};
-use bevy_render2::color::Color;
+use bevy_app::{App, CoreStage, EventReader, Plugin};
+use bevy_asset::{AddAsset, AssetEvent, Assets, Handle};
+use bevy_ecs::prelude::*;
+use bevy_math::Vec4;
+use bevy_reflect::TypeUuid;
+use bevy_render2::{
+    color::Color,
+    render_command::RenderCommandQueue,
+    render_resource::{BufferId, BufferInfo, BufferUsage},
+    renderer::{RenderResourceContext, RenderResources},
+};
+use bevy_utils::HashSet;
+use crevice::std140::{AsStd140, Std140};
 
-#[derive(Debug, Default, Clone, TypeUuid, Reflect)]
+// TODO: this shouldn't live in the StandardMaterial type
+#[derive(Debug, Clone, Copy)]
+pub struct StandardMaterialGpuData {
+    pub buffer: BufferId,
+}
+
+/// A material with "standard" properties used in PBR lighting
+/// Standard property values with pictures here https://google.github.io/filament/Material%20Properties.pdf
+#[derive(Debug, Clone, TypeUuid)]
 #[uuid = "7494888b-c082-457b-aacf-517228cc0c22"]
 pub struct StandardMaterial {
+    /// Doubles as diffuse albedo for non-metallic, specular for metallic and a mix for everything
+    /// in between.
     pub color: Color,
+    /// Linear perceptual roughness, clamped to [0.089, 1.0] in the shader
+    /// Defaults to minimum of 0.089
+    pub roughness: f32,
+    /// From [0.0, 1.0], dielectric to pure metallic
+    pub metallic: f32,
+    /// Specular intensity for non-metals on a linear scale of [0.0, 1.0]
+    /// defaults to 0.5 which is mapped to 4% reflectance in the shader
+    pub reflectance: f32,
+    // Use a color for user friendliness even though we technically don't use the alpha channel
+    // Might be used in the future for exposure correction in HDR
+    pub emissive: Color,
+    pub gpu_data: Option<StandardMaterialGpuData>,
+}
+
+impl StandardMaterial {
+    pub fn gpu_data(&self) -> Option<&StandardMaterialGpuData> {
+        self.gpu_data.as_ref()
+    }
+}
+
+impl Default for StandardMaterial {
+    fn default() -> Self {
+        StandardMaterial {
+            color: Color::rgb(1.0, 1.0, 1.0),
+            // This is the minimum the roughness is clamped to in shader code
+            // See https://google.github.io/filament/Filament.html#materialsystem/parameterization/
+            // It's the minimum floating point value that won't be rounded down to 0 in the
+            // calculations used. Although technically for 32-bit floats, 0.045 could be
+            // used.
+            roughness: 0.089,
+            // Few materials are purely dielectric or metallic
+            // This is just a default for mostly-dielectric
+            metallic: 0.01,
+            // Minimum real-world reflectance is 2%, most materials between 2-5%
+            // Expressed in a linear scale and equivalent to 4% reflectance see https://google.github.io/filament/Material%20Properties.pdf
+            reflectance: 0.5,
+            emissive: Color::BLACK,
+            gpu_data: None,
+        }
+    }
 }
 
 impl From<Color> for StandardMaterial {
@@ -15,3 +76,112 @@ impl From<Color> for StandardMaterial {
         }
     }
 }
+
+#[derive(Clone, AsStd140)]
+pub struct StandardMaterialUniformData {
+    /// Doubles as diffuse albedo for non-metallic, specular for metallic and a mix for everything
+    /// in between.
+    pub color: Vec4,
+    /// Linear perceptual roughness, clamped to [0.089, 1.0] in the shader
+    /// Defaults to minimum of 0.089
+    pub roughness: f32,
+    /// From [0.0, 1.0], dielectric to pure metallic
+    pub metallic: f32,
+    /// Specular intensity for non-metals on a linear scale of [0.0, 1.0]
+    /// defaults to 0.5 which is mapped to 4% reflectance in the shader
+    pub reflectance: f32,
+    // Use a color for user friendliness even though we technically don't use the alpha channel
+    // Might be used in the future for exposure correction in HDR
+    pub emissive: Vec4,
+}
+
+pub struct StandardMaterialPlugin;
+
+impl Plugin for StandardMaterialPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_asset::<StandardMaterial>().add_system_to_stage(
+            CoreStage::PostUpdate,
+            standard_material_resource_system.system(),
+        );
+    }
+}
+
+pub fn standard_material_resource_system(
+    render_resource_context: Res<RenderResources>,
+    mut render_command_queue: ResMut<RenderCommandQueue>,
+    mut materials: ResMut<Assets<StandardMaterial>>,
+    mut material_events: EventReader<AssetEvent<StandardMaterial>>,
+) {
+    let mut changed_materials = HashSet::default();
+    let render_resource_context = &**render_resource_context;
+    for event in material_events.iter() {
+        match event {
+            AssetEvent::Created { ref handle } => {
+                changed_materials.insert(handle.clone_weak());
+            }
+            AssetEvent::Modified { ref handle } => {
+                changed_materials.insert(handle.clone_weak());
+                // TODO: uncomment this to support mutated materials
+                // remove_current_material_resources(render_resource_context, handle, &mut materials);
+            }
+            AssetEvent::Removed { ref handle } => {
+                remove_current_material_resources(render_resource_context, handle, &mut materials);
+                // if material was modified and removed in the same update, ignore the modification
+                // events are ordered so future modification events are ok
+                changed_materials.remove(handle);
+            }
+        }
+    }
+
+    // update changed material data
+    for changed_material_handle in changed_materials.iter() {
+        if let Some(material) = materials.get_mut(changed_material_handle) {
+            // TODO: this avoids creating new materials each frame because storing gpu data in the material flags it as
+            // modified. this prevents hot reloading and therefore can't be used in an actual impl.
+            if material.gpu_data.is_some() {
+                continue;
+            }
+
+            let value = StandardMaterialUniformData {
+                color: material.color.into(),
+                roughness: material.roughness,
+                metallic: material.metallic,
+                reflectance: material.reflectance,
+                emissive: material.emissive.into(),
+            };
+            let value_std140 = value.as_std140();
+
+            let size = StandardMaterialUniformData::std140_size_static();
+
+            let staging_buffer = render_resource_context.create_buffer_with_data(
+                BufferInfo {
+                    size,
+                    buffer_usage: BufferUsage::COPY_SRC | BufferUsage::MAP_WRITE,
+                    mapped_at_creation: true,
+                },
+                value_std140.as_bytes(),
+            );
+
+            let buffer = render_resource_context.create_buffer(BufferInfo {
+                size,
+                buffer_usage: BufferUsage::COPY_DST | BufferUsage::UNIFORM,
+                mapped_at_creation: false,
+            });
+
+            render_command_queue.copy_buffer_to_buffer(staging_buffer, 0, buffer, 0, size as u64);
+            render_command_queue.free_buffer(staging_buffer);
+
+            material.gpu_data = Some(StandardMaterialGpuData { buffer });
+        }
+    }
+}
+
+fn remove_current_material_resources(
+    render_resource_context: &dyn RenderResourceContext,
+    handle: &Handle<StandardMaterial>,
+    materials: &mut Assets<StandardMaterial>,
+) {
+    if let Some(gpu_data) = materials.get_mut(handle).and_then(|t| t.gpu_data.take()) {
+        render_resource_context.remove_buffer(gpu_data.buffer);
+    }
+}

pipelined/bevy_pbr2/src/render/light.rs

@@ -325,44 +325,46 @@ impl Node for ShadowPassNode {
         world: &World,
     ) -> Result<(), NodeRunError> {
         let view_entity = graph.get_input_entity(Self::IN_VIEW)?;
-        let view_lights = self.main_view_query.get_manual(world, view_entity).unwrap();
-        for view_light_entity in view_lights.lights.iter().copied() {
-            let (view_light, shadow_phase) = self
-                .view_light_query
-                .get_manual(world, view_light_entity)
-                .unwrap();
-            let pass_descriptor = PassDescriptor {
-                color_attachments: Vec::new(),
-                depth_stencil_attachment: Some(RenderPassDepthStencilAttachment {
-                    attachment: TextureAttachment::Id(view_light.depth_texture),
-                    depth_ops: Some(Operations {
-                        load: LoadOp::Clear(1.0),
-                        store: true,
+        if let Some(view_lights) = self.main_view_query.get_manual(world, view_entity).ok() {
+            for view_light_entity in view_lights.lights.iter().copied() {
+                let (view_light, shadow_phase) = self
+                    .view_light_query
+                    .get_manual(world, view_light_entity)
+                    .unwrap();
+                let pass_descriptor = PassDescriptor {
+                    color_attachments: Vec::new(),
+                    depth_stencil_attachment: Some(RenderPassDepthStencilAttachment {
+                        attachment: TextureAttachment::Id(view_light.depth_texture),
+                        depth_ops: Some(Operations {
+                            load: LoadOp::Clear(1.0),
+                            store: true,
+                        }),
+                        stencil_ops: None,
                     }),
-                    stencil_ops: None,
-                }),
-                sample_count: 1,
-            };
-
-            let draw_functions = world.get_resource::<DrawFunctions>().unwrap();
-
-            render_context.begin_render_pass(
-                &pass_descriptor,
-                &mut |render_pass: &mut dyn RenderPass| {
-                    let mut draw_functions = draw_functions.write();
-                    let mut tracked_pass = TrackedRenderPass::new(render_pass);
-                    for drawable in shadow_phase.drawn_things.iter() {
-                        let draw_function = draw_functions.get_mut(drawable.draw_function).unwrap();
-                        draw_function.draw(
-                            world,
-                            &mut tracked_pass,
-                            view_light_entity,
-                            drawable.draw_key,
-                            drawable.sort_key,
-                        );
-                    }
-                },
-            );
+                    sample_count: 1,
+                };
+
+                let draw_functions = world.get_resource::<DrawFunctions>().unwrap();
+
+                render_context.begin_render_pass(
+                    &pass_descriptor,
+                    &mut |render_pass: &mut dyn RenderPass| {
+                        let mut draw_functions = draw_functions.write();
+                        let mut tracked_pass = TrackedRenderPass::new(render_pass);
+                        for drawable in shadow_phase.drawn_things.iter() {
+                            let draw_function =
+                                draw_functions.get_mut(drawable.draw_function).unwrap();
+                            draw_function.draw(
+                                world,
+                                &mut tracked_pass,
+                                view_light_entity,
+                                drawable.draw_key,
+                                drawable.sort_key,
+                            );
+                        }
+                    },
+                );
+            }
         }
 
         Ok(())