TypeLayout Rework

examples/api_showcase/src/main.rs

@@ -1,15 +1,16 @@
 #![allow(unused, clippy::no_effect)]
+use shame::gpu_layout;
 use shame as sm;
 use shame::prelude::*;
 use shame::aliases::*;
 
 #[rustfmt::skip]
 fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::EncodingErrors> {
- 
+
     // start a pipeline encoding with the default settings.
     // (in the `shame_wgpu` examples, this is wrapped by the `Gpu` object)
-    // 
-    // compared to earlier versions of `shame`, pipeline 
+    //
+    // compared to earlier versions of `shame`, pipeline
     // encoding is no longer based on a closure, but based on a
     // RAII guard `sm::EncodingGuard<...>` instead.
     // That way you can use the `?` operator for your own
@@ -60,7 +61,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     // only supported in vertex buffers, not storage/uniform buffers.
     // This is reflected in the traits that are derived for `MyVertexFormat`.
     //
-    // note: vertex layouts support #[gpu_repr(packed)] to prevent padding 
+    // note: vertex layouts support #[gpu_repr(packed)] to prevent padding
     // between fields of a struct, which often happens with 3 dimensional vectors
     #[derive(sm::GpuLayout)]
     struct MyVertexFormat {
@@ -76,7 +77,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     // import storage or uniform buffers via the `group0` iterator
     //
     // these iterators exist so that you can abstract them away in your own
-    // api-specific layer that suits your needs such that you can represent 
+    // api-specific layer that suits your needs such that you can represent
     // bind groups as types.
     //
     // `Transforms` is checked for compatibility with `TransformsOnCpu` here.
@@ -85,7 +86,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     // (once rusts const-generics are more powerful this may be moved to compile-time)
     let xforms_sto: sm::Buffer<Transforms, sm::mem::Storage> = group0.next();
     let xforms_uni: sm::Buffer<Transforms, sm::mem::Uniform> = group0.next();
-    
+
     // conditional code generation based on pipeline parameter
     if some_param > 0 {
         // if not further specified, defaults to `sm::mem::Storage`
@@ -99,7 +100,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     let my_vec3 = sm::vec!(1.0, 2.0, 3.0);
     let my_vec4 = sm::vec!(my_vec3, 0.0); // component concatenation, like usual in shaders
     let my_vec4 = my_vec3.extend(0.0); // or like this
-    
+
     let my_normal = sm::vec!(1.0, 1.0, 0.0).normalize();
     let rgb = my_normal.remap(-1.0..=1.0, 0.0..=1.0); // remap linear ranges (instead of " * 0.5 + 0.5")
 
@@ -117,7 +118,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     let k = alpha.rsub1().sqrt().rsub1(); // same as above
 
     // iterate over components of vec
-    let sum: f32x1 = my_vec4.into_iter().map(|x| x * x).sum(); 
+    let sum: f32x1 = my_vec4.into_iter().map(|x| x * x).sum();
 
     let linear = xform.resize() as f32x3x3; // generic matrix resize
     let linear = linear * sm::mat::id(); // generic identity matrix
@@ -162,8 +163,8 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     my_vec.y.set(3.0);
 
     // rusts `if/while/for` means conditional code generation and loop-unrolling,
-    // 
-    // therefore shader control flow uses closures. 
+    //
+    // therefore shader control flow uses closures.
     // The api is designed after rusts `bool::then` and the likes:
 
     let rust_bool = true;
@@ -172,12 +173,12 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
 
     let shame_bool = true.to_gpu();
     // condition appears in the shader as `if true { k = 1 }`
-    // (the `move` keyword is required for safety, 
+    // (the `move` keyword is required for safety,
     // but can be turned off via a shame crate-feature)
     shame_bool.then(move || k.set(1));
 
     // a variety of different shader-loop functions also exist
-    
+
     // for loop doesn't appear in the shader, only `k = 1; k = 2; k = 3; ...`
     for i in 0..=10 {
         k.set(i)
@@ -202,7 +203,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
 
     // clipping planes
     let primitive = primitive.clip(mirror_distances);
-    
+
     // use `rasterize`, `rasterize_multisample` or `rasterize_supersample`.
     // Rasterization gives access to the fragment-stage api via `frag`
     let frag = primitive.rasterize(sm::Accuracy::Relaxed);
@@ -225,7 +226,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     // individual partial derivatives are accessible as fields.
     duv.dx;
     duv.dy;
-    
+
     // `fwidth` was renamed to `dxy_manhattan` because "width" is misleading
     frag.quad.dxy_manhattan(uv, sm::GradPrecision::Coarse);
 
@@ -270,7 +271,7 @@ fn make_pipeline(some_param: u32) -> Result<sm::results::RenderPipeline, sm::Enc
     // `shame` makes it impossible to use these features if they don't apply to the situation.
 
     // this causes a compiler error, because Rg8Unorm has no alpha channel:
-    // targets.next::<tfmt::Rg8Unorm>().set_with_alpha_to_coverage(rg); 
+    // targets.next::<tfmt::Rg8Unorm>().set_with_alpha_to_coverage(rg);
 
     // finish the encoding and obtain the pipeline setup info + shader code.
     encoder.finish()
@@ -486,13 +487,13 @@ struct Mat2([[f32; 2]; 2]);
 // tell `shame` about the layout semantics of your cpu types
 // Mat2::layout() == sm::f32x2x2::layout()
 impl sm::CpuLayout for Mat2 {
-    fn cpu_layout() -> sm::TypeLayout { sm::f32x2x2::gpu_layout() }
+    fn cpu_layout() -> sm::TypeLayout { gpu_layout::<sm::f32x2x2>() }
 }
 
 #[repr(C, align(16))]
 struct Mat4([[f32; 4]; 4]);
 impl sm::CpuLayout for Mat4 {
-    fn cpu_layout() -> sm::TypeLayout { sm::f32x4x4::gpu_layout() }
+    fn cpu_layout() -> sm::TypeLayout { gpu_layout::<sm::f32x4x4>() }
 }
 
 // using "duck-traiting" allows you to define layouts for foreign cpu-types,

examples/hello_triangles/src/util/shame_glam.rs

@@ -2,7 +2,7 @@
 //!
 //! implement `shame::CpuLayout` for some glam types.
 
-use shame as sm;
+use shame::{self as sm, gpu_layout};
 use sm::GpuLayout;
 
 /// circumventing the orphan rule by defining our own trait.
@@ -14,14 +14,14 @@ pub trait CpuLayoutExt {
 
 // glam::Vec4 matches sm::f32x4 in size and alignment
 impl CpuLayoutExt for glam::Vec4 {
-    fn cpu_layout() -> sm::TypeLayout { sm::f32x4::gpu_layout() }
+    fn cpu_layout() -> sm::TypeLayout { gpu_layout::<sm::f32x4>() }
 }
 
 // glam::Vec2 only matches sm::f32x2 if it has 8 byte alignment
 impl CpuLayoutExt for glam::Vec2 {
     fn cpu_layout() -> sm::TypeLayout {
         if align_of::<Self>() == 8 {
-            sm::f32x2::gpu_layout()
+            gpu_layout::<sm::f32x2>()
         } else {
             panic!("glam needs to use the `cuda` crate feature for Vec2 to be 8 byte aligned");
         }
@@ -30,5 +30,5 @@ impl CpuLayoutExt for glam::Vec2 {
 
 // glam::Mat4 matches sm::f32x4x4 in size and alignment
 impl CpuLayoutExt for glam::Mat4 {
-    fn cpu_layout() -> sm::TypeLayout { sm::f32x4x4::gpu_layout() }
+    fn cpu_layout() -> sm::TypeLayout { gpu_layout::<sm::f32x4x4>() }
 }

examples/shame_wgpu/src/conversion.rs

@@ -101,7 +101,7 @@ pub fn sample_type(st: sm::TextureSampleUsageType) -> wgpu::TextureSampleType {
     }
 }
 
-/// converts `tf` into a `wgpu::TextureFormat` if supported. 
+/// converts `tf` into a `wgpu::TextureFormat` if supported.
 /// If `tf` is `ExtraTextureFormats::SurfaceFormat`, then the provided `surface_format` argument
 /// is returned if it is `Some`. Otherwise an error is returned.
 #[rustfmt::skip]
@@ -194,7 +194,7 @@ pub fn texture_format(tf: &dyn sm::TextureFormatId, surface_format: Option<wgpu:
         SmTf::EacR11Snorm          => wgpu::TextureFormat::EacR11Snorm,
         SmTf::EacRg11Unorm         => wgpu::TextureFormat::EacRg11Unorm,
         SmTf::EacRg11Snorm         => wgpu::TextureFormat::EacRg11Snorm,
-        SmTf::Astc { block, channel } => wgpu::TextureFormat::Astc { 
+        SmTf::Astc { block, channel } => wgpu::TextureFormat::Astc {
             block: match block {
                 SmASTCb::B4x4   => wgpu::AstcBlock::B4x4,
                 SmASTCb::B5x4   => wgpu::AstcBlock::B5x4,
@@ -210,12 +210,12 @@ pub fn texture_format(tf: &dyn sm::TextureFormatId, surface_format: Option<wgpu:
                 SmASTCb::B10x10 => wgpu::AstcBlock::B10x10,
                 SmASTCb::B12x10 => wgpu::AstcBlock::B12x10,
                 SmASTCb::B12x12 => wgpu::AstcBlock::B12x12,
-            }, 
+            },
             channel: match channel {
                 SmASTCc::Unorm     => wgpu::AstcChannel::Unorm,
                 SmASTCc::UnormSrgb => wgpu::AstcChannel::UnormSrgb,
                 SmASTCc::Hdr       => wgpu::AstcChannel::Hdr,
-            } 
+            }
         },
     };
     Ok(wtf)
@@ -449,7 +449,7 @@ fn color_writes(write_mask: smr::ChannelWrites) -> wgpu::ColorWrites {
 
 #[rustfmt::skip]
 fn vertex_format(format: smr::VertexAttribFormat) -> Result<wgpu::VertexFormat, ShameToWgpuError> {
-    use smr::ScalarType as S;
+    use shame::any::layout::ScalarType as S;
     use smr::Len as L;
     use wgpu::VertexFormat as W;
     let unsupported = Err(ShameToWgpuError::UnsupportedVertexAttribFormat(format));
@@ -479,10 +479,8 @@ fn vertex_format(format: smr::VertexAttribFormat) -> Result<wgpu::VertexFormat,
             (S::I32, L::X2) => W::Sint32x2,
             (S::I32, L::X3) => W::Sint32x3,
             (S::I32, L::X4) => W::Sint32x4,
-
-            (S::Bool, _) => return unsupported,
         },
-        
+
         smr::VertexAttribFormat::Coarse(p) => {
             use smr::PackedScalarType as PS;
             use smr::PackedFloat as Norm;

examples/type_layout/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "type_layout"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+shame = { path = "../../shame/" }

examples/type_layout/src/main.rs

@@ -0,0 +1,57 @@
+#![allow(dead_code, unused)]
+//! Demonstration of the TypeLayout and TypeLayout Builder API.
+
+use layout::{repr, Repr, SizedStruct};
+use shame::{
+    any::{
+        self,
+        layout::{
+            self, FieldOptions, LayoutableSized, Len, RuntimeSizedArrayField, ScalarType, SizedField, SizedType,
+            UnsizedStruct, Vector, GpuTypeLayout,
+        },
+        U32PowerOf2,
+    },
+    boolx1, f32x1, f32x2, f32x3, f32x4, gpu_layout, Array, GpuLayout, GpuSized, TypeLayout, VertexAttribute,
+    VertexLayout,
+};
+
+fn main() {
+    // We'll start by replicating this struct using `any::layout` types.
+    #[derive(GpuLayout)]
+    struct Vertex {
+        position: f32x3,
+        normal: f32x3,
+        uv: f32x2,
+    }
+
+    // SizedStruct::new immediately takes the first field of the struct, because
+    // structs need to have at least one field.
+    let sized_struct = SizedStruct::new("Vertex", "position", f32x3::layoutable_type_sized())
+        .extend("normal", f32x3::layoutable_type_sized())
+        .extend("uv", f32x1::layoutable_type_sized());
+
+    let storage = GpuTypeLayout::<repr::Storage>::new(sized_struct.clone());
+    let packed = GpuTypeLayout::<repr::Packed>::new(sized_struct);
+    assert_ne!(storage.layout(), packed.layout());
+
+    // Does not exist:
+    // let uniform = GpuTypeLayout::<repr::Uniform>::new(sized_struct.clone());
+
+    // However we can try to upgrade a GpuTypeLayout::<repr::Storage>
+    let uniform = GpuTypeLayout::<repr::Uniform>::try_from(storage.clone()).unwrap();
+
+    // Which if it succeeds, guarantees:
+    assert_eq!(storage.layout(), uniform.layout());
+
+    // // Let's end on a pretty error message
+    let mut sized_struct = SizedStruct::new("D", "a", f32x2::layoutable_type_sized())
+        // This has align of 4 for storage and align of 16 for uniform.
+        .extend("b", Array::<f32x1, shame::Size<1>>::layoutable_type_sized());
+
+    let storage = GpuTypeLayout::<repr::Storage>::new(sized_struct.clone());
+    let uniform_result = GpuTypeLayout::<repr::Uniform>::try_from(storage.clone());
+    match uniform_result {
+        Err(e) => println!("This error is a showcase:\n{}", e),
+        Ok(u_layout) => println!("It unexpectedly worked, ohh no."),
+    }
+}

shame/src/common/po2.rs

@@ -38,10 +38,11 @@ pub enum U32PowerOf2 {
     _2147483648,
 }
 
-impl From<U32PowerOf2> for u32 {
+impl U32PowerOf2 {
+    /// Returns the corresponding u32.
     #[rustfmt::skip]
-    fn from(value: U32PowerOf2) -> Self {
-        match value {
+    pub const fn as_u32(self) -> u32 {
+        match self {
             U32PowerOf2::_1          => 1_u32         ,
             U32PowerOf2::_2          => 2_u32         ,
             U32PowerOf2::_4          => 4_u32         ,
@@ -76,6 +77,18 @@ impl From<U32PowerOf2> for u32 {
             U32PowerOf2::_2147483648 => 2147483648_u32,
         }
     }
+
+    /// Returns the corresponding u64.
+    pub const fn as_u64(self) -> u64 { self.as_u32() as u64 }
+}
+
+impl From<U32PowerOf2> for u32 {
+    fn from(value: U32PowerOf2) -> Self { value.as_u32() }
+}
+
+impl U32PowerOf2 {
+    /// Returns the maximum between `self` and `other`.
+    pub const fn max(self, other: Self) -> Self { if self as u32 > other as u32 { self } else { other } }
 }
 
 #[derive(Debug)]
@@ -89,11 +102,10 @@ impl Display for NotAU32PowerOf2 {
 
 impl std::error::Error for NotAU32PowerOf2 {}
 
-impl TryFrom<u32> for U32PowerOf2 {
-    type Error = NotAU32PowerOf2;
-
-    fn try_from(value: u32) -> Result<Self, Self::Error> {
-        Ok(match value {
+impl U32PowerOf2 {
+    /// Tries to convert a u32 to U32PowerOf2.
+    pub const fn try_from_u32(value: u32) -> Option<Self> {
+        Some(match value {
             1 => U32PowerOf2::_1,
             2 => U32PowerOf2::_2,
             4 => U32PowerOf2::_4,
@@ -126,11 +138,19 @@ impl TryFrom<u32> for U32PowerOf2 {
             536870912 => U32PowerOf2::_536870912,
             1073741824 => U32PowerOf2::_1073741824,
             2147483648 => U32PowerOf2::_2147483648,
-            n => return Err(NotAU32PowerOf2(n)),
+            n => return None,
         })
     }
 }
 
+impl TryFrom<u32> for U32PowerOf2 {
+    type Error = NotAU32PowerOf2;
+
+    fn try_from(value: u32) -> Result<Self, Self::Error> {
+        U32PowerOf2::try_from_u32(value).ok_or(NotAU32PowerOf2(value))
+    }
+}
+
 impl From<U32PowerOf2> for u64 {
     fn from(value: U32PowerOf2) -> Self { u32::from(value) as u64 }
 }

shame/src/common/proc_macro_reexports.rs

@@ -25,10 +25,11 @@ pub use crate::frontend::rust_types::struct_::BufferFields;
 pub use crate::frontend::rust_types::struct_::SizedFields;
 pub use crate::frontend::rust_types::type_layout::FieldLayout;
 pub use crate::frontend::rust_types::type_layout::FieldLayoutWithOffset;
+pub use crate::frontend::rust_types::type_layout::layoutable::FieldOptions;
 pub use crate::frontend::rust_types::type_layout::StructLayout;
-pub use crate::frontend::rust_types::type_layout::StructLayoutError;
+pub use crate::frontend::rust_types::type_layout::Repr;
+pub use crate::frontend::rust_types::type_layout::repr;
 pub use crate::frontend::rust_types::type_layout::TypeLayout;
-pub use crate::frontend::rust_types::type_layout::TypeLayoutRules;
 pub use crate::frontend::rust_types::type_layout::TypeLayoutSemantics;
 pub use crate::frontend::rust_types::type_traits::BindingArgs;
 pub use crate::frontend::rust_types::type_traits::GpuAligned;
@@ -40,6 +41,13 @@ pub use crate::frontend::rust_types::type_traits::NoBools;
 pub use crate::frontend::rust_types::type_traits::NoHandles;
 pub use crate::frontend::rust_types::type_traits::VertexAttribute;
 pub use crate::frontend::rust_types::type_traits::GpuLayoutField;
+pub use crate::frontend::rust_types::type_layout::layoutable::SizedStruct;
+pub use crate::frontend::rust_types::type_layout::layoutable::Layoutable;
+pub use crate::frontend::rust_types::type_layout::layoutable::LayoutableSized;
+pub use crate::frontend::rust_types::type_layout::layoutable::LayoutableType;
+pub use crate::frontend::rust_types::type_layout::layoutable::SizedType;
+pub use crate::frontend::rust_types::type_layout::layoutable::SizedOrArray;
+pub use crate::frontend::rust_types::type_layout::layoutable::builder::StructFromPartsError;
 pub use crate::frontend::rust_types::AsAny;
 pub use crate::frontend::rust_types::GpuType;
 #[allow(missing_docs)]