Introduce ShaderModel.

Cargo.toml

@@ -1,6 +1,7 @@
 [workspace]
 members = [
     "bevy_nannou",
+    "bevy_nannou_derive",
     "bevy_nannou_draw",
     "bevy_nannou_isf",
     "bevy_nannou_video",

bevy_nannou_derive/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "bevy_nannou_derive"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+syn = {  version = "1", features = ["full"] }
+quote = "1.0"
+proc-macro2 = "1.0"
+
+[dev-dependencies]
+bevy = { workspace = true }
+bevy_nannou_draw = { path = "../bevy_nannou_draw" }

bevy_nannou_derive/src/lib.rs

@@ -0,0 +1,75 @@
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::{parse_macro_input, parse_quote, ItemStruct, Lit, Meta, NestedMeta};
+
+#[proc_macro_attribute]
+pub fn shader_model(attr: TokenStream, item: TokenStream) -> TokenStream {
+    let mut input = parse_macro_input!(item as ItemStruct);
+    let attrs = parse_macro_input!(attr as syn::AttributeArgs);
+
+    let (vertex_shader, fragment_shader) = parse_shader_attributes(&attrs);
+
+    let name = &input.ident;
+    let generics = &input.generics;
+    let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
+
+    let vertex_shader_impl = vertex_shader
+        .map(|path| quote! { #path.into() })
+        .unwrap_or_else(|| quote! { ::nannou::prelude::ShaderRef::Default });
+
+    let fragment_shader_impl = fragment_shader
+        .map(|path| quote! { #path.into() })
+        .unwrap_or_else(|| quote! { ::nannou::prelude::ShaderRef::Default });
+
+    // Add derive attributes
+    input
+        .attrs
+        .push(parse_quote!(#[derive(Asset, TypePath, AsBindGroup, Debug, Clone, Default)]));
+
+    let expanded = quote! {
+        #input
+
+        impl #impl_generics ::nannou::prelude::render::ShaderModel for #name #ty_generics #where_clause {
+            fn vertex_shader() -> ::nannou::prelude::ShaderRef {
+                #vertex_shader_impl
+            }
+
+            fn fragment_shader() -> ::nannou::prelude::ShaderRef {
+                #fragment_shader_impl
+            }
+        }
+
+        impl #impl_generics ::nannou::prelude::Material for #name #ty_generics #where_clause {
+            fn vertex_shader() -> ::nannou::prelude::ShaderRef {
+                <Self as ::nannou::prelude::render::ShaderModel>::vertex_shader()
+            }
+
+            fn fragment_shader() -> ::nannou::prelude::ShaderRef {
+                <Self as ::nannou::prelude::render::ShaderModel>::fragment_shader()
+            }
+        }
+    };
+
+    TokenStream::from(expanded)
+}
+
+fn parse_shader_attributes(attrs: &[syn::NestedMeta]) -> (Option<String>, Option<String>) {
+    let mut vertex_shader = None;
+    let mut fragment_shader = None;
+
+    for attr in attrs {
+        if let NestedMeta::Meta(Meta::NameValue(nv)) = attr {
+            if nv.path.is_ident("vertex") {
+                if let Lit::Str(lit) = &nv.lit {
+                    vertex_shader = Some(lit.value());
+                }
+            } else if nv.path.is_ident("fragment") {
+                if let Lit::Str(lit) = &nv.lit {
+                    fragment_shader = Some(lit.value());
+                }
+            }
+        }
+    }
+
+    (vertex_shader, fragment_shader)
+}

bevy_nannou_derive/tests/shader_model_tests.rs

@@ -0,0 +1,60 @@
+use bevy::render::render_resource::ShaderRef;
+use bevy_nannou_derive::shader_model;
+use bevy_nannou_draw::render::ShaderModel;
+
+#[shader_model]
+struct TestMaterial {}
+
+#[test]
+fn test_default_shaders() {
+    assert!(matches!(TestMaterial::vertex_shader(), ShaderRef::Default));
+    assert!(matches!(
+        TestMaterial::fragment_shader(),
+        ShaderRef::Default
+    ));
+}
+
+#[shader_model(vertex = "custom_vertex.wgsl")]
+struct TestVertexMaterial {}
+
+#[test]
+fn test_custom_vertex_shader() {
+    assert!(matches!(
+        TestVertexMaterial::vertex_shader(),
+        ShaderRef::Path(_)
+    ));
+    assert!(matches!(
+        TestVertexMaterial::fragment_shader(),
+        ShaderRef::Default
+    ));
+}
+
+#[shader_model(fragment = "custom_fragment.wgsl")]
+struct TestFragmentMaterial {}
+
+#[test]
+fn test_custom_fragment_shader() {
+    assert!(matches!(
+        TestFragmentMaterial::vertex_shader(),
+        ShaderRef::Default
+    ));
+    assert!(matches!(
+        TestFragmentMaterial::fragment_shader(),
+        ShaderRef::Path(_)
+    ));
+}
+
+#[shader_model(vertex = "custom_vertex.wgsl", fragment = "custom_fragment.wgsl")]
+struct TestBothMaterial {}
+
+#[test]
+fn test_both_custom_shaders() {
+    assert!(matches!(
+        TestBothMaterial::vertex_shader(),
+        ShaderRef::Path(_)
+    ));
+    assert!(matches!(
+        TestBothMaterial::fragment_shader(),
+        ShaderRef::Path(_)
+    ));
+}

bevy_nannou_draw/src/draw/drawing.rs

@@ -1,7 +1,7 @@
 use std::any::TypeId;
 use std::marker::PhantomData;
 
-use bevy::asset::{AsyncWriteExt, UntypedAssetId};
+use bevy::asset::UntypedAssetId;
 use bevy::pbr::{ExtendedMaterial, MaterialExtension};
 use bevy::prelude::*;
 use lyon::path::PathEvent;
@@ -13,7 +13,6 @@ use crate::draw::properties::{
     SetColor, SetDimensions, SetFill, SetOrientation, SetPosition, SetStroke,
 };
 use crate::draw::{Draw, DrawCommand, DrawRef};
-use crate::render::{ExtendedNannouMaterial, NannouMaterial};
 
 /// A **Drawing** in progress.
 ///
@@ -140,51 +139,6 @@ where
         self.finish_inner()
     }
 
-    /// Set the material's fragment shader for the drawing. Note: this shader must have
-    /// been initialized during application setup.
-    #[cfg(feature = "nightly")]
-    pub fn fragment_shader<const FS: &'static str>(
-        mut self,
-    ) -> Drawing<'a, T, ExtendedNannouMaterial<"", FS>> {
-        self.finish_on_drop = false;
-
-        let Drawing {
-            ref draw,
-            index,
-            material_index,
-            ..
-        } = self;
-
-        let state = draw.state.clone();
-        let new_id = UntypedAssetId::Uuid {
-            type_id: TypeId::of::<ExtendedNannouMaterial<"", FS>>(),
-            uuid: Uuid::new_v4(),
-        };
-
-        let material: ExtendedNannouMaterial<"", FS> = Default::default();
-        let mut state = state.write().unwrap();
-        state.materials.insert(new_id.clone(), Box::new(material));
-        // Mark the last material as the new material so that further drawings use the same material
-        // as the parent draw ref.
-        state.last_material = Some(new_id.clone());
-
-        let draw = Draw {
-            state: draw.state.clone(),
-            context: draw.context.clone(),
-            material: new_id.clone(),
-            window: draw.window,
-            _material: Default::default(),
-        };
-
-        Drawing::<'a, T, ExtendedMaterial<StandardMaterial, NannouMaterial<"", FS>>> {
-            draw: DrawRef::Owned(draw),
-            index,
-            material_index,
-            finish_on_drop: true,
-            _ty: PhantomData,
-        }
-    }
-
     // Map the the parent's material to a new material type, taking ownership over the
     // draw instance clone.
     pub fn map_material<F>(mut self, map: F) -> Drawing<'a, T, M>
@@ -921,35 +875,35 @@ where
     T: Into<Primitive>,
     M: MaterialExtension + Default,
 {
-    pub fn roughness(mut self, roughness: f32) -> Self {
+    pub fn roughness(self, roughness: f32) -> Self {
         self.map_material(|mut material| {
             material.base.perceptual_roughness = roughness;
             material
         })
     }
 
-    pub fn metallic(mut self, metallic: f32) -> Self {
+    pub fn metallic(self, metallic: f32) -> Self {
         self.map_material(|mut material| {
             material.base.metallic = metallic;
             material
         })
     }
 
-    pub fn base_color<C: Into<Color>>(mut self, color: C) -> Self {
+    pub fn base_color<C: Into<Color>>(self, color: C) -> Self {
         self.map_material(|mut material| {
             material.base.base_color = color.into();
             material
         })
     }
 
-    pub fn emissive<C: Into<Color>>(mut self, color: C) -> Self {
+    pub fn emissive<C: Into<Color>>(self, color: C) -> Self {
         self.map_material(|mut material| {
             material.base.emissive = color.into().to_linear();
             material
         })
     }
 
-    pub fn texture(mut self, texture: &Handle<Image>) -> Self {
+    pub fn texture(self, texture: &Handle<Image>) -> Self {
         self.map_material(|mut material| {
             material.base.base_color_texture = Some(texture.clone());
             material

bevy_nannou_draw/src/draw/instanced.rs

@@ -19,7 +19,7 @@ use bevy::{
         render_asset::RenderAssets,
         render_phase::{
             AddRenderCommand, DrawFunctions, PhaseItem, PhaseItemExtraIndex, RenderCommand,
-            RenderCommandResult, SetItemPipeline, SortedRenderPhase, TrackedRenderPass,
+            RenderCommandResult, SetItemPipeline, TrackedRenderPass,
         },
         render_resource::*,
         renderer::RenderDevice,

bevy_nannou_draw/src/draw/mesh/mod.rs

@@ -1,7 +1,5 @@
 //! Items related to the custom mesh type used by the `Draw` API.
 
-use std::ops::{Deref, DerefMut};
-
 use bevy::prelude::*;
 use bevy::render::mesh::{Indices, PrimitiveTopology, VertexAttributeValues};
 use bevy::render::render_asset::RenderAssetUsages;

bevy_nannou_draw/src/draw/mod.rs

@@ -4,27 +4,24 @@
 
 use std::any::{Any, TypeId};
 use std::marker::PhantomData;
-use std::ops::{Deref, DerefMut};
+use std::ops::Deref;
 use std::sync::{Arc, RwLock};
 
 use bevy::asset::UntypedAssetId;
-use bevy::ecs::world::Command;
 use bevy::prelude::*;
 use bevy::render::render_resource as wgpu;
 use bevy::render::render_resource::{BlendComponent, BlendState};
 use bevy::utils::{HashMap, HashSet};
 use lyon::path::PathEvent;
 use uuid::Uuid;
 
-use crate::draw::instanced::{InstanceMaterialData, Instanced};
-use crate::draw::mesh::MeshExt;
-use crate::draw::render::RenderPrimitive;
-use crate::render::DefaultNannouMaterial;
-
 pub use self::background::Background;
 pub use self::drawing::{Drawing, DrawingContext};
 use self::primitive::Primitive;
 pub use self::theme::Theme;
+use crate::draw::instanced::{InstanceMaterialData, Instanced};
+use crate::draw::mesh::MeshExt;
+use crate::render::DefaultNannouMaterial;
 
 pub mod background;
 mod drawing;

bevy_nannou_draw/src/draw/primitive/mesh.rs

@@ -27,14 +27,6 @@ pub struct PrimitiveMesh {
 #[derive(Clone, Debug, Default)]
 struct FillColor(Option<Color>);
 
-// A simple iterator for flattening a fixed-size array of indices.
-struct FlattenIndices<I> {
-    iter: I,
-    index: usize,
-    vertex_start_index: usize,
-    current: [usize; 3],
-}
-
 pub type DrawingMesh<'a, M> = Drawing<'a, PrimitiveMesh, M>;
 
 impl Vertexless {
@@ -311,7 +303,8 @@ impl PrimitiveMesh {
     fn new(
         vertex_range: ops::Range<usize>,
         index_range: ops::Range<usize>,
-        texture_handle: Option<Handle<Image>>,
+        // TODO: remove this?
+        _texture_handle: Option<Handle<Image>>,
     ) -> Self {
         let orientation = Default::default();
         let position = Default::default();
@@ -553,29 +546,6 @@ impl draw::render::RenderPrimitive for PrimitiveMesh {
     }
 }
 
-impl<I> Iterator for FlattenIndices<I>
-where
-    I: Iterator<Item = [usize; 3]>,
-{
-    type Item = usize;
-    fn next(&mut self) -> Option<Self::Item> {
-        loop {
-            if self.index < self.current.len() {
-                let ix = self.current[self.index];
-                self.index += 1;
-                return Some(self.vertex_start_index + ix);
-            }
-            match self.iter.next() {
-                None => return None,
-                Some(trio) => {
-                    self.current = trio;
-                    self.index = 0;
-                }
-            }
-        }
-    }
-}
-
 impl SetOrientation for PrimitiveMesh {
     fn properties(&mut self) -> &mut orientation::Properties {
         SetOrientation::properties(&mut self.orientation)

bevy_nannou_draw/src/draw/primitive/path.rs

@@ -68,6 +68,7 @@ pub struct Path {
     orientation: orientation::Properties,
     path_event_src: PathEventSource,
     options: Options,
+    // TODO: remove this?
     texture_handle: Option<Handle<Image>>,
 }
 

bevy_nannou_draw/src/draw/render/mod.rs

@@ -1,5 +1,3 @@
-use std::hash::Hash;
-
 use bevy::prelude::*;
 use lyon::path::PathEvent;
 use lyon::tessellation::{FillTessellator, StrokeTessellator};

bevy_nannou_draw/src/lib.rs

@@ -1,5 +1,3 @@
-#![cfg_attr(feature = "nightly", feature(adt_const_params))]
-
 use bevy::prelude::*;
 
 use crate::render::NannouRenderPlugin;