add uniform field attribute

bevy_derive/Cargo.toml

@@ -13,5 +13,6 @@ proc-macro = true
 syn = "1.0"
 quote = "1.0"
 Inflector = { version = "0.11.4", default-features = false }
+darling = "0.10.2"
 
 [dev-dependencies]

bevy_derive/src/lib.rs

@@ -1,9 +1,10 @@
 extern crate proc_macro;
 
+use darling::FromMeta;
 use inflector::Inflector;
 use proc_macro::TokenStream;
 use quote::{format_ident, quote};
-use syn::{parse_macro_input, Data, DataStruct, DeriveInput, Fields};
+use syn::{parse_macro_input, Data, DataStruct, DeriveInput, Field, Fields};
 
 #[proc_macro_derive(EntityArchetype)]
 pub fn derive_entity_archetype(input: TokenStream) -> TokenStream {
@@ -29,10 +30,19 @@ pub fn derive_entity_archetype(input: TokenStream) -> TokenStream {
         }
     })
 }
+#[derive(FromMeta, Debug, Default)]
+struct UniformAttributeArgs {
+    #[darling(default)]
+    pub ignore: Option<bool>,
+    #[darling(default)]
+    pub shader_def: Option<String>,
+}
 
-#[proc_macro_derive(Uniforms)]
+#[proc_macro_derive(Uniforms, attributes(uniform))]
 pub fn derive_uniforms(input: TokenStream) -> TokenStream {
+    const UNIFORM_ATTRIBUTE_NAME: &'static str = "uniform";
     let ast = parse_macro_input!(input as DeriveInput);
+
     let fields = match &ast.data {
         Data::Struct(DataStruct {
             fields: Fields::Named(fields),
@@ -41,19 +51,67 @@ pub fn derive_uniforms(input: TokenStream) -> TokenStream {
         _ => panic!("expected a struct with named fields"),
     };
 
+    let uniform_fields = fields
+        .iter()
+        .map(|f| {
+            (
+                f,
+                f.attrs
+                    .iter()
+                    .find(|a| {
+                        a.path.get_ident().as_ref().unwrap().to_string() == UNIFORM_ATTRIBUTE_NAME
+                    })
+                    .map(|a| {
+                        UniformAttributeArgs::from_meta(&a.parse_meta().unwrap())
+                            .unwrap_or_else(|_err| UniformAttributeArgs::default())
+                    }),
+            )
+        })
+        .collect::<Vec<(&Field, Option<UniformAttributeArgs>)>>();
+
+    let active_uniform_fields = uniform_fields
+        .iter()
+        .filter(|(_field, attrs)| {
+            attrs.is_none()
+                || match attrs.as_ref().unwrap().ignore {
+                    Some(ignore) => !ignore,
+                    None => true,
+                }
+        })
+        .map(|(f, _attr)| *f)
+        .collect::<Vec<&Field>>();
+
+    let shader_defs = uniform_fields
+        .iter()
+        .filter(|(_f, attrs)| match attrs {
+            Some(attrs) => attrs.shader_def.is_some(),
+            None => false,
+        })
+        .map(|(f, attrs)| {
+            // attrs is guaranteed to be set because we checked in filter
+            let shader_def = attrs.as_ref().unwrap().shader_def.as_ref().unwrap();
+            if shader_def.len() == 0 {
+                f.ident.as_ref().unwrap().to_string()
+            } else {
+                shader_def.to_string()
+            }
+        })
+        .collect::<Vec<String>>();
+
     let struct_name = &ast.ident;
     let struct_name_screaming_snake = struct_name.to_string().to_screaming_snake_case();
     let info_ident = format_ident!("{}_UNIFORM_INFO", struct_name_screaming_snake);
     let layout_ident = format_ident!("{}_UNIFORM_LAYOUTS", struct_name_screaming_snake);
-    let layout_arrays = (0..fields.len()).map(|_| quote!(&[]));
-    let uniform_name_uniform_info = fields
+    let layout_arrays = (0..active_uniform_fields.len()).map(|_| quote!(&[]));
+    let uniform_name_uniform_info = active_uniform_fields
         .iter()
         .map(|field| format!("{}_{}", struct_name, field.ident.as_ref().unwrap()))
         .collect::<Vec<String>>();
-    let get_uniform_bytes_field_name = fields.iter().map(|field| &field.ident);
+    let get_uniform_bytes_field_name = active_uniform_fields.iter().map(|field| &field.ident);
     let get_uniform_bytes_uniform_name = uniform_name_uniform_info.clone();
     let get_uniform_info_uniform_name = uniform_name_uniform_info.clone();
-    let get_uniform_info_array_refs = (0..fields.len()).map(|i| quote!(&#info_ident[#i]));
+    let get_uniform_info_array_refs =
+        (0..active_uniform_fields.len()).map(|i| quote!(&#info_ident[#i]));
 
     TokenStream::from(quote! {
         const #info_ident: &[UniformInfo] = &[
@@ -92,6 +150,12 @@ pub fn derive_uniforms(input: TokenStream) -> TokenStream {
                     _ => None,
                 }
             }
+
+            fn get_shader_defs(&self) -> Vec<&'static str> {
+                vec![
+                    #(#shader_defs,)*
+                ]
+            }
         }
     })
 }

bevy_legion/src/storage.rs

@@ -1377,7 +1377,7 @@ pub struct ComponentResourceSet {
 
 impl ComponentResourceSet {
     /// Gets the version of the component slice.
-    pub fn version(&self) -> u64 { unsafe { (*self.version.get()) } }
+    pub fn version(&self) -> u64 { unsafe { *self.version.get() } }
 
     /// Gets a raw pointer to the start of the component slice.
     ///

src/render/render_graph_2/renderers/wgpu_renderer.rs

@@ -305,6 +305,7 @@ impl WgpuRenderer {
     }
 
     // TODO: remove me
+    #[allow(dead_code)]
     fn setup_dynamic_entity_shader_uniforms(
         &mut self,
         world: &World,

src/render/render_graph_2/uniform.rs

@@ -41,6 +41,7 @@ pub trait AsUniforms {
     fn get_uniform_info(&self, name: &str) -> Option<&UniformInfo>;
     fn get_uniform_layouts(&self) -> &[&[UniformPropertyType]];
     fn get_uniform_bytes(&self, name: &str) -> Option<Vec<u8>>;
+    fn get_shader_defs(&self) -> Vec<&'static str>;
     // TODO: support zero-copy uniforms
     // fn get_uniform_bytes_ref(&self, name: &str) -> Option<&[u8]>;
 }

src/render/render_graph_2/uniforms/local_to_world.rs

@@ -40,4 +40,8 @@ impl AsUniforms for bevy_transform::prelude::LocalToWorld {
             _ => None,
         }
     }
+
+    fn get_shader_defs(&self) -> std::vec::Vec<&'static str> {
+        Vec::new()
+    }
 }

src/render/render_graph_2/uniforms/standard_material.rs

@@ -11,4 +11,6 @@ use bevy_derive::Uniforms;
 #[derive(Uniforms)]
 pub struct StandardMaterial {
     pub albedo: Vec4,
+    // #[uniform(ignore,shader_def="Hi")]
+    // pub enable_thing: bool,
 }