2 files changed, 125 insertions, 45 deletions

diff --git a/alligator_resources/src/lib.rs b/alligator_resources/src/lib.rs
index b85eab1..0f7b544 100644
--- a/alligator_resources/src/lib.rs
+++ b/alligator_resources/src/lib.rs
@@ -5,4 +5,12 @@
 
 pub mod texture;
 
-struct ResourceManager {}
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+pub enum Priority {
+	Unnecessary,
+	Possible(u8),
+	Eventual(u8),
+	Urgent,
+}
+
+pub struct ResourceManager {}
diff --git a/alligator_resources/src/texture.rs b/alligator_resources/src/texture.rs
index f1d34fc..9aca56d 100644
--- a/alligator_resources/src/texture.rs
+++ b/alligator_resources/src/texture.rs
@@ -2,12 +2,15 @@ use std::collections::HashMap;
 use std::mem::{self, MaybeUninit};
 use std::path::Path;
 use std::sync::atomic::{AtomicUsize, Ordering};
+use std::sync::Arc;
 
 use image::{GenericImage, ImageBuffer};
 use texture_packer::exporter::ImageExporter;
 use texture_packer::{Frame, TexturePacker, TexturePackerConfig};
 use thiserror::Error;
 
+use crate::Priority;
+
 static NEXT_TEXTURE_ID: AtomicUsize = AtomicUsize::new(0);
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
@@ -82,12 +85,12 @@ fn texture_size(image: &Rgba16Texture) -> usize {
 	image.len() * mem::size_of::<image::Rgba<u16>>()
 }
 
-struct ImageFile {
+struct TextureFile {
 	path: Box<Path>,
-	texture: Option<Rgba16Texture>,
+	texture: Option<Arc<Rgba16Texture>>,
 }
 
-impl ImageFile {
+impl TextureFile {
 	#[allow(clippy::missing_const_for_fn)]
 	fn new(path: impl AsRef<Path>) -> Self {
 		Self {
@@ -97,21 +100,21 @@ impl ImageFile {
 	}
 
 	fn open(path: impl AsRef<Path>) -> Result<Self, LoadError> {
-		let texture = image::open(&path).map_err(convert_image_load_error)?;
-		let texture = texture.to_rgba16();
-		let texture = vec_image_to_box(texture);
+		let mut this = Self::new(path);
+		this.load()?;
 
-		Ok(Self {
-			path: path.as_ref().into(),
-			texture: Some(texture),
-		})
+		Ok(this)
+	}
+
+	const fn is_loaded(&self) -> bool {
+		self.texture.is_some()
 	}
 
 	fn load(&mut self) -> Result<&Rgba16Texture, LoadError> {
 		if self.texture.is_none() {
 			let texture = image::open(&self.path).map_err(convert_image_load_error)?;
 			let texture = texture.to_rgba16();
-			let texture = vec_image_to_box(texture);
+			let texture = Arc::new(vec_image_to_box(texture));
 			self.texture = Some(texture);
 		}
 
@@ -123,14 +126,99 @@ impl ImageFile {
 	}
 
 	fn allocated_size(&self) -> usize {
-		self.texture
-			.as_ref()
-			.map_or(0, |texture| texture.len() * mem::size_of::<u16>())
+		self.texture.as_ref().map_or(0, |t| texture_size(t))
+	}
+}
+
+enum TextureBuffer {
+	Memory(Arc<Rgba16Texture>),
+	Disk(TextureFile),
+}
+
+struct Texture {
+	priority: Priority,
+	buffer: TextureBuffer,
+}
+
+impl Texture {
+	fn from_buffer(texture: Rgba16Texture) -> Self {
+		Self {
+			priority: Priority::Urgent,
+			buffer: TextureBuffer::Memory(Arc::new(texture)),
+		}
+	}
+
+	fn from_path(path: impl AsRef<Path>, priority: Priority) -> Self {
+		Self {
+			priority,
+			buffer: TextureBuffer::Disk(TextureFile::new(path)),
+		}
+	}
+
+	const fn priority(&self) -> Priority {
+		self.priority
+	}
+
+	fn set_priority(&mut self, priority: Priority) {
+		self.priority = priority;
+	}
+
+	fn load_texture(&mut self) -> Result<&Rgba16Texture, LoadError> {
+		match &mut self.buffer {
+			TextureBuffer::Memory(ref texture) => Ok(texture),
+			TextureBuffer::Disk(file) => file.load(),
+		}
+	}
+}
+
+pub struct TextureRef<'a> {
+	id: TextureId,
+	texture: Arc<Rgba16Texture>,
+	manager: &'a TextureManager,
+}
+
+impl<'a> TextureRef<'a> {
+	fn texture_width(&self) -> u32 {
+		self.texture.width()
+	}
+
+	fn texture_height(&self) -> u32 {
+		self.texture.height()
+	}
+
+	#[allow(clippy::missing_const_for_fn)]
+	fn texture(&self) -> &Rgba16Texture {
+		&self.texture
+	}
+
+	// TODO: it's safer to replace this with a position thingy
+	#[must_use]
+	pub fn atlas_x(&self) -> f32 {
+		self.manager
+			.subtexture_x(self.id)
+			.expect("not in texture atlas")
+	}
+
+	#[must_use]
+	pub fn atlas_y(&self) -> f32 {
+		self.manager
+			.subtexture_y(self.id)
+			.expect("not in texture atlas")
+	}
+
+	#[must_use]
+	pub fn width(&self) -> f32 {
+		self.manager.texture_width(self)
+	}
+
+	#[must_use]
+	pub fn height(&self) -> f32 {
+		self.manager.texture_height(self)
 	}
 }
 
 pub struct TextureManager {
-	textures: HashMap<TextureId, Rgba16Texture>,
+	textures: HashMap<TextureId, Texture>,
 	packer: TexturePacker<'static, Rgba16Texture, TextureId>,
 	atlas: Rgba16Texture, // cached texture atlas
 	width: u32,
@@ -179,32 +267,22 @@ impl TextureManager {
 		}
 	}
 
-	pub fn load_to_atlas(&mut self, id: TextureId) {
-		let texture = self.texture(id);
-		if self.packer.pack_own(id, texture.clone()).is_err() {
-			let texture = self.texture(id);
+	pub fn load_to_atlas(&mut self, id: TextureId, texture: &TextureRef) {
+		let get_texture = || texture.texture().clone();
+
+		if self.packer.pack_own(id, get_texture()).is_err() {
+			let texture = get_texture();
 			self.resize_atlas(self.width + texture.width(), self.height + texture.height());
 
-			let texture = self.texture(id);
 			self.packer
-				.pack_own(id, texture.clone())
+				.pack_own(id, get_texture())
 				.expect("packer is still too small after resizing");
 		}
 	}
 
-	/// Resize the texture atlas
+	/// Clear and resize the texture atlas
 	pub fn resize_atlas(&mut self, width: u32, height: u32) {
-		let old_packer = &self.packer;
-		let mut new_packer = packer(width, height);
-
-		for id in old_packer.get_frames().keys() {
-			let texture = self.texture(*id).clone();
-			new_packer
-				.pack_own(*id, texture)
-				.expect("resized packer is too small to hold subtextures");
-		}
-
-		self.packer = new_packer;
+		self.packer = packer(width, height);
 	}
 
 	/// Clear the texture atlas
@@ -228,6 +306,7 @@ impl TextureManager {
 		let texture = texture.map_err(convert_image_decoding)?;
 		let texture = texture.into_rgba16();
 		let texture = vec_image_to_box(texture);
+		let texture = Texture::from_buffer(texture);
 
 		self.textures.insert(id, texture);
 
@@ -237,7 +316,6 @@ impl TextureManager {
 	pub fn atlas(&mut self) -> &Rgba16Texture {
 		let atlas = {
 			profiling::scope!("export atlas");
-			// TODO unexpect_msg?
 			ImageExporter::export(&self.packer).expect("ImageExporter error?")
 		};
 
@@ -249,10 +327,6 @@ impl TextureManager {
 		&self.atlas
 	}
 
-	fn texture(&self, id: TextureId) -> &Rgba16Texture {
-		self.textures.get(&id).expect("invalid TextureId")
-	}
-
 	/// Get the subtexture in the texture atlas
 	fn subtexture(&self, id: TextureId) -> Option<&Frame<TextureId>> {
 		self.packer.get_frame(&id)
@@ -277,16 +351,14 @@ impl TextureManager {
 	/// Get the width of a texture
 	#[must_use]
 	#[allow(clippy::cast_precision_loss)]
-	pub fn texture_width(&self, id: TextureId) -> f32 {
-		let width = self.texture(id).width();
-		width as f32 / self.width as f32
+	pub fn texture_width(&self, texture: &TextureRef) -> f32 {
+		texture.texture_width() as f32 / self.width as f32
 	}
 
 	/// Get the height of a texture
 	#[must_use]
 	#[allow(clippy::cast_precision_loss)]
-	pub fn texture_height(&self, id: TextureId) -> f32 {
-		let height = self.texture(id).height();
-		height as f32 / self.height as f32
+	pub fn texture_height(&self, texture: &TextureRef) -> f32 {
+		texture.texture_height() as f32 / self.height as f32
 	}
 }