Refactor Globals and View structs into separate shaders (#7512)

fixes #6799 

# Objective

We should be able to reuse the `Globals` or `View` shader struct definitions from anywhere (including third party plugins) without needing to worry about defining unrelated shader defs.
Also we'd like to refactor these structs to not be repeatedly defined.

## Solution

Refactor both `Globals` and `View` into separate importable shaders.
Use the imports throughout.

Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>

Author: torsteingrindvik

crates/bevy_pbr/src/render/mesh_view_types.wgsl

@@ -1,16 +1,7 @@
 #define_import_path bevy_pbr::mesh_view_types
 
-struct View {
-    view_proj: mat4x4<f32>,
-    inverse_view_proj: mat4x4<f32>,
-    view: mat4x4<f32>,
-    inverse_view: mat4x4<f32>,
-    projection: mat4x4<f32>,
-    inverse_projection: mat4x4<f32>,
-    world_position: vec3<f32>,
-    // viewport(x_origin, y_origin, width, height)
-    viewport: vec4<f32>,
-};
+#import bevy_render::view
+#import bevy_render::globals
 
 struct PointLight {
     // For point lights: the lower-right 2x2 values of the projection matrix [2][2] [2][3] [3][2] [3][3]
@@ -119,18 +110,3 @@ struct ClusterOffsetsAndCounts {
     data: array<vec4<u32>, 1024u>,
 };
 #endif
-
-struct Globals {
-    // The time since startup in seconds
-    // Wraps to 0 after 1 hour.
-    time: f32,
-    // The delta time since the previous frame in seconds
-    delta_time: f32,
-    // Frame count since the start of the app.
-    // It wraps to zero when it reaches the maximum value of a u32.
-    frame_count: u32,
-#ifdef SIXTEEN_BYTE_ALIGNMENT
-    // WebGL2 structs must be 16 byte aligned.
-    _wasm_padding: f32
-#endif
-}

crates/bevy_render/src/globals.rs

@@ -1,19 +1,25 @@
 use crate::{
     extract_resource::ExtractResource,
+    prelude::Shader,
     render_resource::{ShaderType, UniformBuffer},
     renderer::{RenderDevice, RenderQueue},
     Extract, ExtractSchedule, RenderApp, RenderSet,
 };
 use bevy_app::{App, Plugin};
+use bevy_asset::{load_internal_asset, HandleUntyped};
 use bevy_core::FrameCount;
 use bevy_ecs::prelude::*;
-use bevy_reflect::Reflect;
+use bevy_reflect::{Reflect, TypeUuid};
 use bevy_time::Time;
 
+pub const GLOBALS_TYPE_HANDLE: HandleUntyped =
+    HandleUntyped::weak_from_u64(Shader::TYPE_UUID, 17924628719070609599);
+
 pub struct GlobalsPlugin;
 
 impl Plugin for GlobalsPlugin {
     fn build(&self, app: &mut App) {
+        load_internal_asset!(app, GLOBALS_TYPE_HANDLE, "globals.wgsl", Shader::from_wgsl);
         app.register_type::<GlobalsUniform>();
 
         if let Ok(render_app) = app.get_sub_app_mut(RenderApp) {

crates/bevy_render/src/globals.wgsl

@@ -0,0 +1,16 @@
+#define_import_path bevy_render::globals
+
+struct Globals {
+    // The time since startup in seconds
+    // Wraps to 0 after 1 hour.
+    time: f32,
+    // The delta time since the previous frame in seconds
+    delta_time: f32,
+    // Frame count since the start of the app.
+    // It wraps to zero when it reaches the maximum value of a u32.
+    frame_count: u32,
+#ifdef SIXTEEN_BYTE_ALIGNMENT
+    // WebGL2 structs must be 16 byte aligned.
+    _webgl2_padding: f32
+#endif
+};

crates/bevy_render/src/view/mod.rs

@@ -1,13 +1,14 @@
 pub mod visibility;
 pub mod window;
 
+use bevy_asset::{load_internal_asset, HandleUntyped};
 pub use visibility::*;
 pub use window::*;
 
 use crate::{
     camera::ExtractedCamera,
     extract_resource::{ExtractResource, ExtractResourcePlugin},
-    prelude::Image,
+    prelude::{Image, Shader},
     render_asset::RenderAssets,
     render_phase::ViewRangefinder3d,
     render_resource::{DynamicUniformBuffer, ShaderType, Texture, TextureView},
@@ -18,7 +19,7 @@ use crate::{
 use bevy_app::{App, Plugin};
 use bevy_ecs::prelude::*;
 use bevy_math::{Mat4, UVec4, Vec3, Vec4};
-use bevy_reflect::Reflect;
+use bevy_reflect::{Reflect, TypeUuid};
 use bevy_transform::components::GlobalTransform;
 use bevy_utils::HashMap;
 use std::sync::atomic::{AtomicUsize, Ordering};
@@ -27,10 +28,15 @@ use wgpu::{
     TextureFormat, TextureUsages,
 };
 
+pub const VIEW_TYPE_HANDLE: HandleUntyped =
+    HandleUntyped::weak_from_u64(Shader::TYPE_UUID, 15421373904451797197);
+
 pub struct ViewPlugin;
 
 impl Plugin for ViewPlugin {
     fn build(&self, app: &mut App) {
+        load_internal_asset!(app, VIEW_TYPE_HANDLE, "view.wgsl", Shader::from_wgsl);
+
         app.register_type::<ComputedVisibility>()
             .register_type::<ComputedVisibilityFlags>()
             .register_type::<Msaa>()

crates/bevy_render/src/view/view.wgsl

@@ -0,0 +1,13 @@
+#define_import_path bevy_render::view
+
+struct View {
+    view_proj: mat4x4<f32>,
+    inverse_view_proj: mat4x4<f32>,
+    view: mat4x4<f32>,
+    inverse_view: mat4x4<f32>,
+    projection: mat4x4<f32>,
+    inverse_projection: mat4x4<f32>,
+    world_position: vec3<f32>,
+    // viewport(x_origin, y_origin, width, height)
+    viewport: vec4<f32>,
+};

crates/bevy_sprite/src/mesh2d/mesh2d_view_types.wgsl

@@ -1,28 +1,4 @@
 #define_import_path bevy_sprite::mesh2d_view_types
 
-struct View {
-    view_proj: mat4x4<f32>,
-    inverse_view_proj: mat4x4<f32>,
-    view: mat4x4<f32>,
-    inverse_view: mat4x4<f32>,
-    projection: mat4x4<f32>,
-    inverse_projection: mat4x4<f32>,
-    world_position: vec3<f32>,
-    // viewport(x_origin, y_origin, width, height)
-    viewport: vec4<f32>,
-};
-
-struct Globals {
-    // The time since startup in seconds
-    // Wraps to 0 after 1 hour.
-    time: f32,
-    // The delta time since the previous frame in seconds
-    delta_time: f32,
-    // Frame count since the start of the app.
-    // It wraps to zero when it reaches the maximum value of a u32.
-    frame_count: u32,
-#ifdef SIXTEEN_BYTE_ALIGNMENT
-    // WebGL2 structs must be 16 byte aligned.
-    _wasm_padding: f32
-#endif
-}
+#import bevy_render::view
+#import bevy_render::globals

crates/bevy_sprite/src/render/sprite.wgsl

@@ -2,17 +2,8 @@
 #import bevy_core_pipeline::tonemapping
 #endif
 
-struct View {
-    view_proj: mat4x4<f32>,
-    inverse_view_proj: mat4x4<f32>,
-    view: mat4x4<f32>,
-    inverse_view: mat4x4<f32>,
-    projection: mat4x4<f32>,
-    inverse_projection: mat4x4<f32>,
-    world_position: vec3<f32>,
-    // viewport(x_origin, y_origin, width, height)
-    viewport: vec4<f32>,
-};
+#import bevy_render::view
+
 @group(0) @binding(0)
 var<uniform> view: View;
 

crates/bevy_ui/src/render/ui.wgsl

@@ -1,14 +1,5 @@
-struct View {
-    view_proj: mat4x4<f32>,
-    inverse_view_proj: mat4x4<f32>,
-    view: mat4x4<f32>,
-    inverse_view: mat4x4<f32>,
-    projection: mat4x4<f32>,
-    inverse_projection: mat4x4<f32>,
-    world_position: vec3<f32>,
-    // viewport(x_origin, y_origin, width, height)
-    viewport: vec4<f32>,
-};
+#import bevy_render::view
+
 @group(0) @binding(0)
 var<uniform> view: View;