refactor(engine): make model & material assets use asset dependencies

1 files changed, 92 insertions, 7 deletions

diff --git a/engine/src/material.rs b/engine/src/material.rs
index 5f77950..ae0751b 100644
--- a/engine/src/material.rs
+++ b/engine/src/material.rs
@@ -1,4 +1,14 @@
-use crate::asset::{Asset, Handle as AssetHandle};
+use ecs::sole::Single;
+
+use crate::asset::{
+    Asset,
+    Assets,
+    Dependency as AssetDependency,
+    Event as AssetEvent,
+    Events as AssetEvents,
+    Handle as AssetHandle,
+    Label as AssetLabel,
+};
 use crate::builder;
 use crate::color::{Color, Rgb};
 use crate::ecs::Component;
@@ -18,6 +28,7 @@ pub struct Material
     pub diffuse_map: Option<AssetHandle<Texture>>,
     pub specular_map: Option<AssetHandle<Texture>>,
     pub shininess: f32,
+    pub loading_textures: Vec<(LoadingTextureName, AssetLabel<'static>)>,
 }
 
 impl Material
@@ -46,12 +57,26 @@ impl Default for Material
 
 impl Asset for Material
 {
-    fn dependencies(&self) -> impl Iterator<Item = crate::asset::Dependency<'_>>
+    fn dependencies(&self) -> impl Iterator<Item = AssetDependency<'_>>
     {
-        [].into_iter()
+        self.loading_textures.iter().map(|(_, texture_label)| {
+            AssetDependency::new::<Texture>(AssetLabel {
+                path: (&*texture_label.path).into(),
+                name: texture_label.name.as_deref().map(Into::into),
+            })
+        })
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[non_exhaustive]
+pub enum LoadingTextureName
+{
+    AmbientMap,
+    DiffuseMap,
+    SpecularMap,
+}
+
 /// [`Material`] builder.
 #[derive(Debug, Clone)]
 pub struct Builder
@@ -63,6 +88,7 @@ pub struct Builder
     diffuse_map: Option<AssetHandle<Texture>>,
     specular_map: Option<AssetHandle<Texture>>,
     shininess: f32,
+    loading_textures: Vec<(LoadingTextureName, AssetLabel<'static>)>,
 }
 
 impl Builder
@@ -78,6 +104,7 @@ impl Builder
             diffuse_map: None,
             specular_map: None,
             shininess: 32.0,
+            loading_textures: Vec::with_capacity(3),
         }
     }
 
@@ -130,6 +157,17 @@ impl Builder
     }
 
     #[must_use]
+    pub fn loading_texture(
+        mut self,
+        name: LoadingTextureName,
+        asset_label: AssetLabel<'static>,
+    ) -> Self
+    {
+        self.loading_textures.push((name, asset_label));
+        self
+    }
+
+    #[must_use]
     pub fn shininess(mut self, shininess: f32) -> Self
     {
         self.shininess = shininess;
@@ -138,11 +176,8 @@ impl Builder
     }
 
     /// Builds a new [`Material`].
-    ///
-    /// # Panics
-    /// Will panic if no ambient map, diffuse map or specular map is set.
     #[must_use]
-    pub const fn build(self) -> Material
+    pub fn build(self) -> Material
     {
         Material {
             ambient: self.ambient,
@@ -152,6 +187,7 @@ impl Builder
             diffuse_map: self.diffuse_map,
             specular_map: self.specular_map,
             shininess: self.shininess,
+            loading_textures: self.loading_textures,
         }
     }
 }
@@ -210,3 +246,52 @@ impl Default for FlagsBuilder
         Self::new()
     }
 }
+
+pub(crate) fn set_stored_materials_texture_handles(
+    mut assets: Single<Assets>,
+    asset_events: Single<AssetEvents>,
+)
+{
+    let assets = assets.get_mut().unwrap();
+    let asset_events = asset_events.get().unwrap();
+
+    for AssetEvent::Stored(asset_id, ..) in asset_events.iter_last_tick() {
+        let asset_handle = AssetHandle::<Material>::from_id(*asset_id);
+
+        if !assets.is_loaded_and_has_type(&asset_handle) {
+            continue;
+        }
+
+        let Some(material_textures) = assets.get(&asset_handle).map(|mat| {
+            mat.loading_textures
+                .iter()
+                .map(|(tex_name, tex_label)| {
+                    (
+                        *tex_name,
+                        assets.get_handle_to_loaded::<Texture>(tex_label.clone()),
+                    )
+                })
+                .collect::<Vec<_>>()
+        }) else {
+            unreachable!();
+        };
+
+        let Some(material) = assets.get_mut(&asset_handle) else {
+            unreachable!();
+        };
+
+        for (tex_name, tex_asset) in material_textures {
+            let Some(tex_asset) = tex_asset else {
+                unreachable!();
+            };
+
+            let dst = match tex_name {
+                LoadingTextureName::AmbientMap => &mut material.ambient_map,
+                LoadingTextureName::DiffuseMap => &mut material.diffuse_map,
+                LoadingTextureName::SpecularMap => &mut material.specular_map,
+            };
+
+            *dst = Some(tex_asset);
+        }
+    }
+}