Move image/svg handling into `iced_graphics`

The `TextureStore` trait is implemented by the atlas, and can also be
implemented in the glow renderer or in a software renderer.

The API here may be improved in the future, but API stability is
presumably not a huge issue since these types will only be used by
renderer backends.

1 files changed, 41 insertions, 27 deletions

diff --git a/wgpu/src/image/raster.rs b/graphics/src/image/raster.rs
index 2b4d4af3..f9672dd5 100644
--- a/wgpu/src/image/raster.rs
+++ b/graphics/src/image/raster.rs
@@ -1,18 +1,27 @@
-use crate::image::atlas::{self, Atlas};
+//! Raster image loading and caching
+
 use iced_native::image;
 use std::collections::{HashMap, HashSet};
 
 use bitflags::bitflags;
 
+use super::{TextureStore, TextureStoreEntry};
+
+/// Entry in cache corresponding to an image handle
 #[derive(Debug)]
-pub enum Memory {
-    Host(::image_rs::ImageBuffer<::image_rs::Bgra<u8>, Vec<u8>>),
-    Device(atlas::Entry),
+pub enum Memory<T: TextureStore> {
+    /// Image data on host
+    Host(::image_rs::ImageBuffer<::image_rs::Rgba<u8>, Vec<u8>>),
+    /// Texture store entry
+    Device(T::Entry),
+    /// Image not found
     NotFound,
+    /// Invalid image data
     Invalid,
 }
 
-impl Memory {
+impl<T: TextureStore> Memory<T> {
+    /// Width and height of image
     pub fn dimensions(&self) -> (u32, u32) {
         match self {
             Memory::Host(image) => image.dimensions(),
@@ -23,21 +32,16 @@ impl Memory {
     }
 }
 
+/// Caches image raster data
 #[derive(Debug)]
-pub struct Cache {
-    map: HashMap<u64, Memory>,
+pub struct Cache<T: TextureStore> {
+    map: HashMap<u64, Memory<T>>,
     hits: HashSet<u64>,
 }
 
-impl Cache {
-    pub fn new() -> Self {
-        Self {
-            map: HashMap::new(),
-            hits: HashSet::new(),
-        }
-    }
-
-    pub fn load(&mut self, handle: &image::Handle) -> &mut Memory {
+impl<T: TextureStore> Cache<T> {
+    /// Load image
+    pub fn load(&mut self, handle: &image::Handle) -> &mut Memory<T> {
         if self.contains(handle) {
             return self.get(handle).unwrap();
         }
@@ -53,7 +57,7 @@ impl Cache {
                         })
                         .unwrap_or_else(Operation::empty);
 
-                    Memory::Host(operation.perform(image.to_bgra8()))
+                    Memory::Host(operation.perform(image.to_rgba8()))
                 } else {
                     Memory::NotFound
                 }
@@ -65,7 +69,7 @@ impl Cache {
                             .ok()
                             .unwrap_or_else(Operation::empty);
 
-                    Memory::Host(operation.perform(image.to_bgra8()))
+                    Memory::Host(operation.perform(image.to_rgba8()))
                 } else {
                     Memory::Invalid
                 }
@@ -91,19 +95,19 @@ impl Cache {
         self.get(handle).unwrap()
     }
 
+    /// Load image and upload raster data
     pub fn upload(
         &mut self,
         handle: &image::Handle,
-        device: &wgpu::Device,
-        encoder: &mut wgpu::CommandEncoder,
-        atlas: &mut Atlas,
-    ) -> Option<&atlas::Entry> {
+        state: &mut T::State<'_>,
+        store: &mut T,
+    ) -> Option<&T::Entry> {
         let memory = self.load(handle);
 
         if let Memory::Host(image) = memory {
             let (width, height) = image.dimensions();
 
-            let entry = atlas.upload(width, height, image, device, encoder)?;
+            let entry = store.upload(width, height, image, state)?;
 
             *memory = Memory::Device(entry);
         }
@@ -115,7 +119,8 @@ impl Cache {
         }
     }
 
-    pub fn trim(&mut self, atlas: &mut Atlas) {
+    /// Trim cache misses from cache
+    pub fn trim(&mut self, store: &mut T, state: &mut T::State<'_>) {
         let hits = &self.hits;
 
         self.map.retain(|k, memory| {
@@ -123,7 +128,7 @@ impl Cache {
 
             if !retain {
                 if let Memory::Device(entry) = memory {
-                    atlas.remove(entry);
+                    store.remove(entry, state);
                 }
             }
 
@@ -133,13 +138,13 @@ impl Cache {
         self.hits.clear();
     }
 
-    fn get(&mut self, handle: &image::Handle) -> Option<&mut Memory> {
+    fn get(&mut self, handle: &image::Handle) -> Option<&mut Memory<T>> {
         let _ = self.hits.insert(handle.id());
 
         self.map.get_mut(&handle.id())
     }
 
-    fn insert(&mut self, handle: &image::Handle, memory: Memory) {
+    fn insert(&mut self, handle: &image::Handle, memory: Memory<T>) {
         let _ = self.map.insert(handle.id(), memory);
     }
 
@@ -148,6 +153,15 @@ impl Cache {
     }
 }
 
+impl<T: TextureStore> Default for Cache<T> {
+    fn default() -> Self {
+        Self {
+            map: HashMap::new(),
+            hits: HashSet::new(),
+        }
+    }
+}
+
 bitflags! {
     struct Operation: u8 {
         const FLIP_HORIZONTALLY = 0b001;