Implement particle groups, enabling simple particle trails.

This commit essentially allows multiple effects to share the same underlying buffer. Such sub-effects are known as *particle groups*. An effect may have up to 32 particle groups, each with its own capacity. Every modifier specifies which particle groups it affects. Spawners always spawn into particle group 0; this restriction was implemented for simplicity and can be lifted later. A new modifier has been added, `CloneModifier`. This allows particles to be duplicated into a group on a fixed rate. By cloning particles into a group, particle trails can be created. It's intended that a node graph can be layered on top of particle groups in the future. Particle groups are the most efficient way I can think of to implement node graphs in any case, so this seems to me to be a step toward a node-based editor. Currently, init modifiers don't run on cloned particles. Their age is, however, reset to 0 if present, as this is typically the most useful behavior. Internally, each particle group receives its own update and render invocation. This reduces branching in both shaders, simplifies much of the bookkeeping, and enables ribbon rendering for trails in the future (needed for weapon effects, etc.) The new `worms` example illustrates how trails can be produced with this groups feature.
djeedai · Mar 6, 2024 · 0c49f95 · 0c49f95
1 parent 4933a35
commit 0c49f95
Show file tree

Hide file tree

Showing 36 changed files with 2,314 additions and 1,717 deletions.
diff --git a/Cargo.toml b/Cargo.toml
@@ -144,6 +144,10 @@ required-features = [ "bevy/bevy_winit", "bevy/bevy_pbr", "bevy/png", "3d" ]
 name = "2d"
 required-features = [ "bevy/bevy_winit", "bevy/bevy_sprite", "2d" ]
 
+[[example]]
+name = "worms"
+required-features = [ "bevy/bevy_winit", "bevy/bevy_pbr", "3d" ]
+
 [workspace]
 resolver = "2"
 members = ["."]
diff --git a/assets/circle.png b/assets/circle.png
diff --git a/examples/2d.rs b/examples/2d.rs
@@ -115,7 +115,7 @@ fn setup(
     // By default the asset spawns the particles at Z=0.
     let spawner = Spawner::rate(30.0.into());
     let effect = effects.add(
-        EffectAsset::new(4096, spawner, writer.finish())
+        EffectAsset::new(vec![4096], spawner, writer.finish())
             .with_name("2d")
             .init(init_pos)
             .init(init_vel)

diff --git a/examples/activate.rs b/examples/activate.rs
@@ -11,10 +11,7 @@ use bevy::{
     log::LogPlugin,
     prelude::*,
     render::{
-        camera::{Projection, ScalingMode},
-        render_resource::WgpuFeatures,
-        settings::WgpuSettings,
-        RenderPlugin,
+        camera::ScalingMode, render_resource::WgpuFeatures, settings::WgpuSettings, RenderPlugin,
     },
 };
 #[cfg(feature = "examples_world_inspector")]
@@ -136,7 +133,7 @@ fn setup(
     };
 
     let effect = effects.add(
-        EffectAsset::new(32768, spawner, writer.finish())
+        EffectAsset::new(vec![32768], spawner, writer.finish())
             .with_name("activate")
             .init(init_pos)
             .init(init_vel)

diff --git a/examples/billboard.rs b/examples/billboard.rs
@@ -150,7 +150,7 @@ fn setup(
     let rotation_attr = writer.attr(Attribute::F32_0).expr();
 
     let effect = effects.add(
-        EffectAsset::new(32768, Spawner::rate(64.0.into()), writer.finish())
+        EffectAsset::new(vec![32768], Spawner::rate(64.0.into()), writer.finish())
             .with_name("billboard")
             .with_alpha_mode(bevy_hanabi::AlphaMode::Mask(alpha_cutoff))
             .init(init_pos)

diff --git a/examples/circle.rs b/examples/circle.rs
@@ -145,7 +145,7 @@ fn setup(
 
     let effect = effects.add(
         EffectAsset::new(
-            32768,
+            vec![32768],
             Spawner::burst(32.0.into(), 8.0.into()),
             writer.finish(),
         )

diff --git a/examples/expr.rs b/examples/expr.rs
@@ -104,7 +104,7 @@ fn setup(mut commands: Commands, mut effects: ResMut<Assets<EffectAsset>>) {
     };
 
     let effect = effects.add(
-        EffectAsset::new(32768, Spawner::rate(500.0.into()), writer.finish())
+        EffectAsset::new(vec![32768], Spawner::rate(500.0.into()), writer.finish())
             .with_name("whirlwind")
             .init(init_pos)
             .init(init_age)

diff --git a/examples/firework.rs b/examples/firework.rs
@@ -110,7 +110,7 @@ fn setup(mut commands: Commands, mut effects: ResMut<Assets<EffectAsset>>) {
     };
 
     let effect = EffectAsset::new(
-        32768,
+        vec![32768],
         Spawner::burst(2500.0.into(), 2.0.into()),
         writer.finish(),
     )

diff --git a/examples/force_field.rs b/examples/force_field.rs
@@ -18,9 +18,7 @@ use bevy::{
     core_pipeline::tonemapping::Tonemapping,
     log::LogPlugin,
     prelude::*,
-    render::{
-        camera::Projection, render_resource::WgpuFeatures, settings::WgpuSettings, RenderPlugin,
-    },
+    render::{render_resource::WgpuFeatures, settings::WgpuSettings, RenderPlugin},
 };
 #[cfg(feature = "examples_world_inspector")]
 use bevy_inspector_egui::quick::WorldInspectorPlugin;
@@ -80,12 +78,7 @@ struct RepulsorMarker(pub bool);
 
 #[cfg(feature = "examples_world_inspector")]
 mod inspector {
-    use bevy::{
-        ecs::system::{Local, Resource},
-        prelude::*,
-        reflect::Reflect,
-        window::PrimaryWindow,
-    };
+    use bevy::{ecs::system::Resource, prelude::*, reflect::Reflect, window::PrimaryWindow};
     use bevy_egui::EguiContext;
     use bevy_hanabi::EffectProperties;
     use bevy_inspector_egui::{inspector_options::std_options::NumberDisplay, prelude::*};
@@ -338,7 +331,7 @@ fn setup(
 
     // Force field effects
     let effect = effects.add(
-        EffectAsset::new(32768, spawner, writer.finish())
+        EffectAsset::new(vec![32768], spawner, writer.finish())
             .with_name("force_field")
             .with_property("repulsor_position", Value::Vector(REPULSOR_POS.into()))
             .with_property("attraction_accel", Value::Scalar(20.0.into()))

diff --git a/examples/gradient.rs b/examples/gradient.rs
@@ -102,7 +102,7 @@ fn setup(
     };
 
     let effect = effects.add(
-        EffectAsset::new(32768, Spawner::rate(1000.0.into()), writer.finish())
+        EffectAsset::new(vec![32768], Spawner::rate(1000.0.into()), writer.finish())
             .with_name("gradient")
             .init(init_pos)
             .init(init_vel)

diff --git a/examples/init.rs b/examples/init.rs
@@ -72,15 +72,19 @@ where
 
     let init = make_modifier(&writer);
 
-    EffectAsset::new(32768, Spawner::once(COUNT.into(), true), writer.finish())
-        .with_name(name)
-        .with_simulation_space(SimulationSpace::Local)
-        .init(init)
-        .render(OrientModifier::new(OrientMode::FaceCameraPosition))
-        .render(SetColorModifier {
-            color: COLOR.into(),
-        })
-        .render(SetSizeModifier { size: SIZE.into() })
+    EffectAsset::new(
+        vec![32768],
+        Spawner::once(COUNT.into(), true),
+        writer.finish(),
+    )
+    .with_name(name)
+    .with_simulation_space(SimulationSpace::Local)
+    .init(init)
+    .render(OrientModifier::new(OrientMode::FaceCameraPosition))
+    .render(SetColorModifier {
+        color: COLOR.into(),
+    })
+    .render(SetSizeModifier { size: SIZE.into() })
 }
 
 fn spawn_effect(

diff --git a/examples/instancing.rs b/examples/instancing.rs
@@ -253,7 +253,7 @@ fn setup(
     };
 
     let effect = effects.add(
-        EffectAsset::new(512, Spawner::rate(50.0.into()), writer.finish())
+        EffectAsset::new(vec![512], Spawner::rate(50.0.into()), writer.finish())
             .with_name("instancing")
             .init(init_pos)
             .init(init_vel)

diff --git a/examples/lifetime.rs b/examples/lifetime.rs
@@ -117,7 +117,7 @@ fn setup(
     };
     let effect1 = effects.add(
         EffectAsset::new(
-            512,
+            vec![512],
             Spawner::burst(50.0.into(), period.into()),
             writer1.finish(),
         )
@@ -172,7 +172,7 @@ fn setup(
     };
     let effect2 = effects.add(
         EffectAsset::new(
-            512,
+            vec![512],
             Spawner::burst(50.0.into(), period.into()),
             writer2.finish(),
         )
@@ -227,7 +227,7 @@ fn setup(
     };
     let effect3 = effects.add(
         EffectAsset::new(
-            512,
+            vec![512],
             Spawner::burst(50.0.into(), period.into()),
             writer3.finish(),
         )

diff --git a/examples/multicam.rs b/examples/multicam.rs
@@ -83,7 +83,7 @@ fn make_effect(color: Color) -> EffectAsset {
         speed: writer.lit(6.).expr(),
     };
 
-    EffectAsset::new(32768, Spawner::rate(5.0.into()), writer.finish())
+    EffectAsset::new(vec![32768], Spawner::rate(5.0.into()), writer.finish())
         .with_name("effect")
         .init(init_pos)
         .init(init_vel)

diff --git a/examples/portal.rs b/examples/portal.rs
@@ -99,7 +99,7 @@ fn setup(mut commands: Commands, mut effects: ResMut<Assets<EffectAsset>>) {
     let tangent_accel = TangentAccelModifier::constant(&mut module, Vec3::ZERO, Vec3::Z, 30.);
 
     let effect1 = effects.add(
-        EffectAsset::new(32768, Spawner::rate(5000.0.into()), module)
+        EffectAsset::new(vec![16384, 16384], Spawner::rate(5000.0.into()), module)
             .with_name("portal")
             .init(init_pos)
             .init(init_age)

diff --git a/examples/random.rs b/examples/random.rs
@@ -107,7 +107,7 @@ fn setup(
 
     let effect = effects.add(
         EffectAsset::new(
-            32768,
+            vec![32768],
             Spawner::burst(CpuValue::Uniform((1., 100.)), CpuValue::Uniform((1., 4.))),
             writer.finish(),
         )

diff --git a/examples/spawn.rs b/examples/spawn.rs
@@ -135,7 +135,7 @@ fn setup(
     };
 
     let effect1 = effects.add(
-        EffectAsset::new(32768, Spawner::rate(500.0.into()), writer1.finish())
+        EffectAsset::new(vec![32768], Spawner::rate(500.0.into()), writer1.finish())
             .with_name("emit:rate")
             .with_property("my_accel", Vec3::new(0., -3., 0.).into())
             .init(init_pos1)
@@ -198,15 +198,19 @@ fn setup(
         speed: writer2.lit(2.).expr(),
     };
     let effect2 = effects.add(
-        EffectAsset::new(32768, Spawner::once(1000.0.into(), true), writer2.finish())
-            .with_name("emit:once")
-            .init(init_pos2)
-            .init(init_vel2)
-            .init(init_age2)
-            .init(init_lifetime2)
-            .render(ColorOverLifetimeModifier {
-                gradient: gradient2,
-            }),
+        EffectAsset::new(
+            vec![32768],
+            Spawner::once(1000.0.into(), true),
+            writer2.finish(),
+        )
+        .with_name("emit:once")
+        .init(init_pos2)
+        .init(init_vel2)
+        .init(init_age2)
+        .init(init_lifetime2)
+        .render(ColorOverLifetimeModifier {
+            gradient: gradient2,
+        }),
     );
 
     commands
@@ -266,7 +270,7 @@ fn setup(
 
     let effect3 = effects.add(
         EffectAsset::new(
-            32768,
+            vec![32768],
             Spawner::burst(400.0.into(), 3.0.into()),
             writer3.finish(),
         )

diff --git a/examples/spawn_on_command.rs b/examples/spawn_on_command.rs
@@ -168,7 +168,7 @@ fn setup(
     let init_vel = SetAttributeModifier::new(Attribute::VELOCITY, velocity.expr());
 
     let effect = effects.add(
-        EffectAsset::new(32768, spawner, writer.finish())
+        EffectAsset::new(vec![32768], spawner, writer.finish())
             .with_name("spawn_on_command")
             .with_property("spawn_color", 0xFFFFFFFFu32.into())
             .with_property("normal", Vec3::ZERO.into())

diff --git a/examples/visibility.rs b/examples/visibility.rs
@@ -119,7 +119,7 @@ fn setup(
     };
 
     let mut asset = EffectAsset::new(
-        4096,
+        vec![4096],
         Spawner::burst(50.0.into(), 15.0.into()),
         writer.finish(),
     )