Remove Need for Sprite Size Sync System (#2632)

# Objective

- Prevent the need to have a system that synchronizes sprite sizes with their images

## Solution

- Read the sprite size from the image asset when rendering the sprite
- Replace the `size` and `resize_mode` fields of `Sprite` with a `custom_size: Option<Vec2>` that will modify the sprite's rendered size to be different than the image size, but only if it is `Some(Vec2)`

examples/tools/bevymark_pipelined.rs

@@ -3,10 +3,10 @@ use bevy::{
     diagnostic::{Diagnostics, FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
     ecs::prelude::*,
     input::Input,
-    math::{Vec2, Vec3},
+    math::Vec3,
     prelude::{App, AssetServer, Handle, MouseButton, Transform},
     render2::{camera::OrthographicCameraBundle, color::Color, texture::Image},
-    sprite2::{PipelinedSpriteBundle, Sprite},
+    sprite2::PipelinedSpriteBundle,
     window::WindowDescriptor,
     PipelinedDefaultPlugins,
 };
@@ -177,10 +177,6 @@ fn spawn_birds(
             .spawn_bundle(PipelinedSpriteBundle {
                 // material: bird_material.0.clone(),
                 texture: texture.clone(),
-                sprite: Sprite {
-                    size: Vec2::new(250.0, 250.0),
-                    ..Default::default()
-                },
                 transform: Transform {
                     translation: Vec3::new(bird_x, bird_y, bird_z),
                     scale: Vec3::splat(BIRD_SCALE),

pipelined/bevy_sprite2/src/lib.rs

@@ -25,9 +25,7 @@ pub struct SpritePlugin;
 
 impl Plugin for SpritePlugin {
     fn build(&self, app: &mut App) {
-        app.add_asset::<TextureAtlas>()
-            .register_type::<Sprite>()
-            .add_system_to_stage(CoreStage::PostUpdate, sprite_auto_resize_system);
+        app.add_asset::<TextureAtlas>().register_type::<Sprite>();
         let render_app = app.sub_app(RenderApp);
         render_app
             .init_resource::<ExtractedSprites>()

pipelined/bevy_sprite2/src/render/mod.rs

@@ -190,16 +190,21 @@ pub fn extract_sprites(
 ) {
     let mut extracted_sprites = Vec::new();
     for (sprite, transform, handle) in sprite_query.iter() {
-        if !images.contains(handle) {
+        let image = if let Some(image) = images.get(handle) {
+            image
+        } else {
             continue;
-        }
+        };
+        let size = image.texture_descriptor.size;
 
         extracted_sprites.push(ExtractedSprite {
             atlas_size: None,
             transform: transform.compute_matrix(),
             rect: Rect {
                 min: Vec2::ZERO,
-                max: sprite.size,
+                max: sprite
+                    .custom_size
+                    .unwrap_or_else(|| Vec2::new(size.width as f32, size.height as f32)),
             },
             handle: handle.clone_weak(),
         });

pipelined/bevy_sprite2/src/sprite.rs

@@ -1,65 +1,15 @@
-use bevy_asset::{Assets, Handle};
-use bevy_ecs::prelude::{Query, Res};
 use bevy_math::Vec2;
-use bevy_reflect::{Reflect, ReflectDeserialize, TypeUuid};
-use bevy_render2::texture::Image;
-use serde::{Deserialize, Serialize};
+use bevy_reflect::{Reflect, TypeUuid};
 
 #[derive(Debug, Default, Clone, TypeUuid, Reflect)]
 #[uuid = "7233c597-ccfa-411f-bd59-9af349432ada"]
 #[repr(C)]
 pub struct Sprite {
-    pub size: Vec2,
+    /// Flip the sprite along the X axis
     pub flip_x: bool,
+    /// Flip the sprite along the Y axis
     pub flip_y: bool,
-    pub resize_mode: SpriteResizeMode,
-}
-
-/// Determines how `Sprite` resize should be handled
-#[derive(Debug, Clone, Copy, PartialEq, Serialize, Deserialize, Reflect)]
-#[reflect_value(PartialEq, Serialize, Deserialize)]
-pub enum SpriteResizeMode {
-    Manual,
-    Automatic,
-}
-
-impl Default for SpriteResizeMode {
-    fn default() -> Self {
-        SpriteResizeMode::Automatic
-    }
-}
-
-impl Sprite {
-    /// Creates new `Sprite` with `SpriteResizeMode::Manual` value for `resize_mode`
-    pub fn new(size: Vec2) -> Self {
-        Self {
-            size,
-            resize_mode: SpriteResizeMode::Manual,
-            flip_x: false,
-            flip_y: false,
-        }
-    }
-}
-
-/// System that resizes sprites that have their resize mode set to automatic
-pub fn sprite_auto_resize_system(
-    textures: Res<Assets<Image>>,
-    mut query: Query<(&mut Sprite, &Handle<Image>)>,
-) {
-    for (mut sprite, image_handle) in query.iter_mut() {
-        match sprite.resize_mode {
-            SpriteResizeMode::Manual => continue,
-            SpriteResizeMode::Automatic => {
-                if let Some(image) = textures.get(image_handle) {
-                    let extent = image.texture_descriptor.size;
-                    let texture_size = Vec2::new(extent.width as f32, extent.height as f32);
-                    // only set sprite size if it has changed (this check prevents change
-                    // detection from triggering)
-                    if sprite.size != texture_size {
-                        sprite.size = texture_size;
-                    }
-                }
-            }
-        }
-    }
+    /// An optional custom size for the sprite that will be used when rendering, instead of the size
+    /// of the sprite's image
+    pub custom_size: Option<Vec2>,
 }