Implementing Reflect on *MeshBuilder types (#17600)

# Objective

- Most of the `*MeshBuilder` classes are not implementing `Reflect`

## Solution

- Implementing `Reflect` for all `*MeshBuilder` were is possible.
- Make sure all `*MeshBuilder` implements `Default`.
- Adding new `MeshBuildersPlugin` that registers all `*MeshBuilder`
types.

## Testing

- `cargo run -p ci`
- Tested some examples like `3d_scene` just in case something was
broken.

crates/bevy_mesh/src/primitives/dim2.rs

@@ -12,10 +12,12 @@ use bevy_math::{
     },
     FloatExt, Vec2,
 };
+use bevy_reflect::prelude::*;
 use wgpu_types::PrimitiveTopology;
 
 /// A builder used for creating a [`Mesh`] with a [`Circle`] shape.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct CircleMeshBuilder {
     /// The [`Circle`] shape.
     pub circle: Circle,
@@ -98,7 +100,8 @@ impl From<Circle> for Mesh {
 /// It's expected that more will be added in the future, such as a variant that causes the texture to be
 /// scaled to fit the bounding box of the shape, which would be good for packed textures only including the
 /// portion of the circle that is needed to display.
-#[derive(Copy, Clone, Debug, PartialEq)]
+#[derive(Copy, Clone, Debug, PartialEq, Reflect)]
+#[reflect(Default, Debug)]
 #[non_exhaustive]
 pub enum CircularMeshUvMode {
     /// Treats the shape as a mask over a circle of equal size and radius,
@@ -119,7 +122,8 @@ impl Default for CircularMeshUvMode {
 ///
 /// The resulting mesh will have a UV-map such that the center of the circle is
 /// at the center of the texture.
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct CircularSectorMeshBuilder {
     /// The sector shape.
     pub sector: CircularSector,
@@ -256,7 +260,8 @@ impl From<CircularSector> for Mesh {
 ///
 /// The resulting mesh will have a UV-map such that the center of the circle is
 /// at the center of the texture.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct CircularSegmentMeshBuilder {
     /// The segment shape.
     pub segment: CircularSegment,
@@ -402,6 +407,8 @@ impl From<CircularSegment> for Mesh {
 ///
 /// You must verify that the `vertices` are not concave when constructing this type. You can
 /// guarantee this by creating a [`ConvexPolygon`] first, then calling [`ConvexPolygon::mesh()`].
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Debug)]
 pub struct ConvexPolygonMeshBuilder<const N: usize> {
     pub vertices: [Vec2; N],
 }
@@ -451,11 +458,23 @@ impl<const N: usize> From<ConvexPolygon<N>> for Mesh {
 }
 
 /// A builder used for creating a [`Mesh`] with a [`RegularPolygon`] shape.
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct RegularPolygonMeshBuilder {
     circumradius: f32,
     sides: u32,
 }
 
+impl Default for RegularPolygonMeshBuilder {
+    /// Returns the default [`RegularPolygonMeshBuilder`] with six sides (a hexagon) and a circumradius of `0.5`.
+    fn default() -> Self {
+        Self {
+            circumradius: 0.5,
+            sides: 6,
+        }
+    }
+}
+
 impl RegularPolygonMeshBuilder {
     /// Creates a new [`RegularPolygonMeshBuilder`] from the radius of a circumcircle and a number
     /// of sides.
@@ -513,7 +532,8 @@ impl From<RegularPolygon> for Mesh {
 }
 
 /// A builder used for creating a [`Mesh`] with an [`Ellipse`] shape.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct EllipseMeshBuilder {
     /// The [`Ellipse`] shape.
     pub ellipse: Ellipse,
@@ -617,6 +637,8 @@ impl From<Ellipse> for Mesh {
 }
 
 /// A builder for creating a [`Mesh`] with an [`Annulus`] shape.
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct AnnulusMeshBuilder {
     /// The [`Annulus`] shape.
     pub annulus: Annulus,
@@ -747,10 +769,22 @@ impl From<Annulus> for Mesh {
     }
 }
 
+/// A builder for creating a [`Mesh`] with an [`Rhombus`] shape.
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct RhombusMeshBuilder {
     half_diagonals: Vec2,
 }
 
+impl Default for RhombusMeshBuilder {
+    /// Returns the default [`RhombusMeshBuilder`] with a half-horizontal and half-vertical diagonal of `0.5`.
+    fn default() -> Self {
+        Self {
+            half_diagonals: Vec2::splat(0.5),
+        }
+    }
+}
+
 impl RhombusMeshBuilder {
     /// Creates a new [`RhombusMeshBuilder`] from a horizontal and vertical diagonal size.
     ///
@@ -822,6 +856,8 @@ impl From<Rhombus> for Mesh {
 }
 
 /// A builder used for creating a [`Mesh`] with a [`Triangle2d`] shape.
+#[derive(Clone, Copy, Debug, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub struct Triangle2dMeshBuilder {
     triangle: Triangle2d,
 }
@@ -897,10 +933,21 @@ impl From<Triangle2d> for Mesh {
 }
 
 /// A builder used for creating a [`Mesh`] with a [`Rectangle`] shape.
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct RectangleMeshBuilder {
     half_size: Vec2,
 }
 
+impl Default for RectangleMeshBuilder {
+    /// Returns the default [`RectangleMeshBuilder`] with a half-width and half-height of `0.5`.
+    fn default() -> Self {
+        Self {
+            half_size: Vec2::splat(0.5),
+        }
+    }
+}
+
 impl RectangleMeshBuilder {
     /// Creates a new [`RectangleMeshBuilder`] from a full width and height.
     ///
@@ -966,7 +1013,8 @@ impl From<Rectangle> for Mesh {
 }
 
 /// A builder used for creating a [`Mesh`] with a [`Capsule2d`] shape.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct Capsule2dMeshBuilder {
     /// The [`Capsule2d`] shape.
     pub capsule: Capsule2d,

crates/bevy_mesh/src/primitives/dim3/capsule.rs

@@ -1,9 +1,11 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{ops, primitives::Capsule3d, Vec2, Vec3};
+use bevy_reflect::prelude::*;
 
 /// Manner in which UV coordinates are distributed vertically.
-#[derive(Clone, Copy, Debug, Default)]
+#[derive(Clone, Copy, Debug, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub enum CapsuleUvProfile {
     /// UV space is distributed by how much of the capsule consists of the hemispheres.
     #[default]
@@ -16,7 +18,8 @@ pub enum CapsuleUvProfile {
 }
 
 /// A builder used for creating a [`Mesh`] with a [`Capsule3d`] shape.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct Capsule3dMeshBuilder {
     /// The [`Capsule3d`] shape.
     pub capsule: Capsule3d,

crates/bevy_mesh/src/primitives/dim3/cone.rs

@@ -1,9 +1,11 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{ops, primitives::Cone, Vec3};
+use bevy_reflect::prelude::*;
 
 /// Anchoring options for [`ConeMeshBuilder`]
-#[derive(Debug, Copy, Clone, Default)]
+#[derive(Debug, Copy, Clone, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub enum ConeAnchor {
     #[default]
     /// Midpoint between the tip of the cone and the center of its base.
@@ -15,7 +17,8 @@ pub enum ConeAnchor {
 }
 
 /// A builder used for creating a [`Mesh`] with a [`Cone`] shape.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct ConeMeshBuilder {
     /// The [`Cone`] shape.
     pub cone: Cone,

crates/bevy_mesh/src/primitives/dim3/conical_frustum.rs

@@ -1,9 +1,11 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{ops, primitives::ConicalFrustum, Vec3};
+use bevy_reflect::prelude::*;
 
 /// A builder used for creating a [`Mesh`] with a [`ConicalFrustum`] shape.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct ConicalFrustumMeshBuilder {
     /// The [`ConicalFrustum`] shape.
     pub frustum: ConicalFrustum,

crates/bevy_mesh/src/primitives/dim3/cuboid.rs

@@ -1,12 +1,24 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{primitives::Cuboid, Vec3};
+use bevy_reflect::prelude::*;
 
 /// A builder used for creating a [`Mesh`] with a [`Cuboid`] shape.
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct CuboidMeshBuilder {
     half_size: Vec3,
 }
 
+impl Default for CuboidMeshBuilder {
+    /// Returns the default [`CuboidMeshBuilder`] with a width, height, and depth of `1.0`.
+    fn default() -> Self {
+        Self {
+            half_size: Vec3::splat(0.5),
+        }
+    }
+}
+
 impl MeshBuilder for CuboidMeshBuilder {
     fn build(&self) -> Mesh {
         let min = -self.half_size;

crates/bevy_mesh/src/primitives/dim3/cylinder.rs

@@ -1,9 +1,11 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{ops, primitives::Cylinder};
+use bevy_reflect::prelude::*;
 
 /// Anchoring options for [`CylinderMeshBuilder`]
-#[derive(Debug, Copy, Clone, Default)]
+#[derive(Debug, Copy, Clone, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub enum CylinderAnchor {
     #[default]
     /// Midpoint between the top and bottom caps of the cylinder
@@ -15,7 +17,8 @@ pub enum CylinderAnchor {
 }
 
 /// A builder used for creating a [`Mesh`] with a [`Cylinder`] shape.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct CylinderMeshBuilder {
     /// The [`Cylinder`] shape.
     pub cylinder: Cylinder,

crates/bevy_mesh/src/primitives/dim3/plane.rs

@@ -1,9 +1,11 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{primitives::Plane3d, Dir3, Quat, Vec2, Vec3};
+use bevy_reflect::prelude::*;
 
 /// A builder used for creating a [`Mesh`] with a [`Plane3d`] shape.
-#[derive(Clone, Copy, Debug, Default)]
+#[derive(Clone, Copy, Debug, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub struct PlaneMeshBuilder {
     /// The [`Plane3d`] shape.
     pub plane: Plane3d,

crates/bevy_mesh/src/primitives/dim3/sphere.rs

@@ -1,6 +1,7 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{ops, primitives::Sphere};
+use bevy_reflect::prelude::*;
 use core::f32::consts::PI;
 use hexasphere::shapes::IcoSphere;
 use thiserror::Error;
@@ -19,7 +20,8 @@ pub enum IcosphereError {
 }
 
 /// A type of sphere mesh.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub enum SphereKind {
     /// An icosphere, a spherical mesh that consists of similar sized triangles.
     Ico {
@@ -46,7 +48,8 @@ impl Default for SphereKind {
 }
 
 /// A builder used for creating a [`Mesh`] with an [`Sphere`] shape.
-#[derive(Clone, Copy, Debug, Default)]
+#[derive(Clone, Copy, Debug, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub struct SphereMeshBuilder {
     /// The [`Sphere`] shape.
     pub sphere: Sphere,

crates/bevy_mesh/src/primitives/dim3/tetrahedron.rs

@@ -2,8 +2,11 @@ use super::triangle3d;
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::primitives::{Tetrahedron, Triangle3d};
+use bevy_reflect::prelude::*;
 
 /// A builder used for creating a [`Mesh`] with a [`Tetrahedron`] shape.
+#[derive(Clone, Copy, Debug, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub struct TetrahedronMeshBuilder {
     tetrahedron: Tetrahedron,
 }

crates/bevy_mesh/src/primitives/dim3/torus.rs

@@ -1,10 +1,12 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{ops, primitives::Torus, Vec3};
+use bevy_reflect::prelude::*;
 use core::ops::RangeInclusive;
 
 /// A builder used for creating a [`Mesh`] with a [`Torus`] shape.
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, Reflect)]
+#[reflect(Default, Debug)]
 pub struct TorusMeshBuilder {
     /// The [`Torus`] shape.
     pub torus: Torus,

crates/bevy_mesh/src/primitives/dim3/triangle3d.rs

@@ -1,8 +1,11 @@
 use crate::{Indices, Mesh, MeshBuilder, Meshable, PrimitiveTopology};
 use bevy_asset::RenderAssetUsages;
 use bevy_math::{primitives::Triangle3d, Vec3};
+use bevy_reflect::prelude::*;
 
 /// A builder used for creating a [`Mesh`] with a [`Triangle3d`] shape.
+#[derive(Clone, Copy, Debug, Default, Reflect)]
+#[reflect(Default, Debug)]
 pub struct Triangle3dMeshBuilder {
     triangle: Triangle3d,
 }

crates/bevy_render/src/mesh/mod.rs

@@ -24,6 +24,36 @@ use bevy_ecs::{
 pub use components::{mark_3d_meshes_as_changed_if_their_assets_changed, Mesh2d, Mesh3d};
 use wgpu::IndexFormat;
 
+/// Registers all [`MeshBuilder`] types.
+pub struct MeshBuildersPlugin;
+
+impl Plugin for MeshBuildersPlugin {
+    fn build(&self, app: &mut App) {
+        // 2D Mesh builders
+        app.register_type::<CircleMeshBuilder>()
+            .register_type::<CircularSectorMeshBuilder>()
+            .register_type::<CircularSegmentMeshBuilder>()
+            .register_type::<RegularPolygonMeshBuilder>()
+            .register_type::<EllipseMeshBuilder>()
+            .register_type::<AnnulusMeshBuilder>()
+            .register_type::<RhombusMeshBuilder>()
+            .register_type::<Triangle2dMeshBuilder>()
+            .register_type::<RectangleMeshBuilder>()
+            .register_type::<Capsule2dMeshBuilder>()
+            // 3D Mesh builders
+            .register_type::<Capsule3dMeshBuilder>()
+            .register_type::<ConeMeshBuilder>()
+            .register_type::<ConicalFrustumMeshBuilder>()
+            .register_type::<CuboidMeshBuilder>()
+            .register_type::<CylinderMeshBuilder>()
+            .register_type::<PlaneMeshBuilder>()
+            .register_type::<SphereMeshBuilder>()
+            .register_type::<TetrahedronMeshBuilder>()
+            .register_type::<TorusMeshBuilder>()
+            .register_type::<Triangle3dMeshBuilder>();
+    }
+}
+
 /// Adds the [`Mesh`] as an asset and makes sure that they are extracted and prepared for the GPU.
 pub struct MeshPlugin;
 
@@ -35,6 +65,7 @@ impl Plugin for MeshPlugin {
             .register_type::<Mesh3d>()
             .register_type::<skinning::SkinnedMesh>()
             .register_type::<Vec<Entity>>()
+            .add_plugins(MeshBuildersPlugin)
             // 'Mesh' must be prepared after 'Image' as meshes rely on the morph target image being ready
             .add_plugins(RenderAssetPlugin::<RenderMesh, GpuImage>::default())
             .add_plugins(MeshAllocatorPlugin)