Use material name for mesh entity's Name when available (#19287)

rendaoer · alice-i-cecile · greeble-dev · web-flow · commit c62ca1a0d36c · 2025-05-20T14:45:04.000Z
# Objective Fixes #19286 ## Solution Use material name for mesh entity's Name when available ## Testing Test code, modified from examples/load_gltf.rs ```rust //! Loads and renders a glTF file as a scene. use bevy::{gltf::GltfMaterialName, prelude::*, scene::SceneInstanceReady}; fn main() { App::new() .add_plugins(DefaultPlugins) .add_systems(Startup, setup) .add_observer(on_scene_load) .run(); } fn setup(mut commands: Commands, asset_server: Res<AssetServer>) { commands.spawn(( Camera3d::default(), Transform::from_xyz(0.7, 0.7, 1.0).looking_at(Vec3::new(0.0, 0.3, 0.0), Vec3::Y), )); commands.spawn((DirectionalLight { shadows_enabled: true, ..default() },)); commands.spawn(SceneRoot(asset_server.load( GltfAssetLabel::Scene(0).from_asset("models/FlightHelmet/FlightHelmet.gltf"), ))); } fn on_scene_load( trigger: Trigger<SceneInstanceReady>, children: Query<&Children>, names: Query<&Name>, material_names: Query<&GltfMaterialName>, ) { let target = trigger.target(); for child in children.iter_descendants(target) { let name = if let Ok(name) = names.get(child) { Some(name.to_string()) } else { None }; let material_name = if let Ok(name) = material_names.get(child) { Some(name.0.clone()) } else { None }; info!("Entity name:{:?} | material name:{:?}", name, material_name); } } ``` --- ## Showcase Run log: <img width="859" alt="Image" src="https://github.com/user-attachments/assets/87daddf3-31e6-41f8-9be2-4b292da9b75a" /> --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Greeble <166992735+greeble-dev@users.noreply.github.com>
diff --git a/crates/bevy_gltf/src/loader/gltf_ext/mesh.rs b/crates/bevy_gltf/src/loader/gltf_ext/mesh.rs
@@ -1,13 +1,17 @@
 use bevy_mesh::PrimitiveTopology;
 
-use gltf::mesh::{Mesh, Mode, Primitive};
+use gltf::{
+    mesh::{Mesh, Mode},
+    Material,
+};
 
 use crate::GltfError;
 
-pub(crate) fn primitive_name(mesh: &Mesh<'_>, primitive: &Primitive) -> String {
+pub(crate) fn primitive_name(mesh: &Mesh<'_>, material: &Material) -> String {
     let mesh_name = mesh.name().unwrap_or("Mesh");
-    if mesh.primitives().len() > 1 {
-        format!("{}.{}", mesh_name, primitive.index())
+
+    if let Some(material_name) = material.name() {
+        format!("{}.{}", mesh_name, material_name)
     } else {
         mesh_name.to_string()
     }
diff --git a/crates/bevy_gltf/src/loader/mod.rs b/crates/bevy_gltf/src/loader/mod.rs
@@ -1464,10 +1464,11 @@ fn load_node(
                     }
 
                     if let Some(name) = material.name() {
-                        mesh_entity.insert(GltfMaterialName(String::from(name)));
+                        mesh_entity.insert(GltfMaterialName(name.to_string()));
                     }
 
-                    mesh_entity.insert(Name::new(primitive_name(&mesh, &primitive)));
+                    mesh_entity.insert(Name::new(primitive_name(&mesh, &material)));
+
                     // Mark for adding skinned mesh
                     if let Some(skin) = gltf_node.skin() {
                         entity_to_skin_index_map.insert(mesh_entity.id(), skin.index());
diff --git a/release-content/migration-guides/rename_spawn_gltf_material_name.md b/release-content/migration-guides/rename_spawn_gltf_material_name.md
@@ -0,0 +1,9 @@
+---
+title: Use Gltf material names for spawned primitive entities
+authors: ["@rendaoer"]
+pull_requests: [19287]
+---
+
+When loading a Gltf scene in Bevy, each mesh primitive will generate an entity and store a `GltfMaterialName` component and `Name` component.
+
+The `Name` components were previously stored as mesh name plus primitive index - for example, `MeshName.0` and `MeshName.1`. To make it easier to view these entities in Inspector-style tools, they are now stored as mesh name plus material name - for example, `MeshName.Material1Name` and `MeshName.Material2Name`.

Original file line number	Diff line number	Diff line change
`@@ -1464,10 +1464,11 @@ fn load_node(`
`1464`	`1464`	`}`
`1465`	`1465`
`1466`	`1466`	`if let Some(name) = material.name() {`
`1467`		`- mesh_entity.insert(GltfMaterialName(String::from(name)));`
	`1467`	`+ mesh_entity.insert(GltfMaterialName(name.to_string()));`
`1468`	`1468`	`}`
`1469`	`1469`
`1470`		`- mesh_entity.insert(Name::new(primitive_name(&mesh, &primitive)));`
	`1470`	`+ mesh_entity.insert(Name::new(primitive_name(&mesh, &material)));`
	`1471`	`+`
`1471`	`1472`	`// Mark for adding skinned mesh`
`1472`	`1473`	`if let Some(skin) = gltf_node.skin() {`
`1473`	`1474`	`entity_to_skin_index_map.insert(mesh_entity.id(), skin.index());`