Adjust layout modifying data transfer ergonomics

Author: 197g

texel/src/buf.rs

@@ -1996,7 +1996,10 @@ mod tests {
                 n
             });
 
-            let target = atomic.as_texels(U16).index(offset..).index(..3 * MAX_ALIGN / 2);
+            let target = atomic
+                .as_texels(U16)
+                .index(offset..)
+                .index(..3 * MAX_ALIGN / 2);
             U16.store_atomic_slice(target, &data[..]);
 
             let mut check = [0; 3 * MAX_ALIGN / 2];

texel/src/image.rs

@@ -10,8 +10,8 @@
 //! advised, probably very common, and the only 'supported' use-case).
 mod atomic;
 mod cell;
+mod data;
 mod raw;
-mod unaligned;
 
 use core::{fmt, ops};
 
@@ -21,12 +21,12 @@ use crate::layout::{
     Bytes, Decay, Layout, Mend, PlaneOf, Raster, RasterMut, Relocate, SliceLayout, Take, TryMend,
 };
 use crate::texel::MAX_ALIGN;
-use crate::{Texel, TexelBuffer};
+use crate::{BufferReuseError, Texel, TexelBuffer};
 
 pub use crate::stride::{StridedBufferMut, StridedBufferRef};
 pub use atomic::{AtomicImage, AtomicImageRef};
 pub use cell::{CellImage, CellImageRef};
-pub use unaligned::{DataCells, DataMut, DataRef};
+pub use data::{DataCells, DataMut, DataRef};
 
 /// A container of allocated bytes, parameterized over the layout.
 ///
@@ -848,6 +848,19 @@ impl<'data, L> ImageMut<'data, L> {
         Some(image.into())
     }
 
+    /// Attempt to modify the layout to a new value, without modifying its type.
+    ///
+    /// Returns an `Err` if the layout does not fit the underlying buffer. Otherwise returns `Ok`
+    /// and overwrites the layout accordingly.
+    ///
+    /// TODO: public name and provide a `set_capacity` for `L = Bytes`?
+    pub(crate) fn try_set_layout(&mut self, layout: L) -> Result<(), BufferReuseError>
+    where
+        L: Layout,
+    {
+        self.inner.try_reuse(layout)
+    }
+
     /// Decay into a image with less specific layout.
     ///
     /// See [`Image::decay`].

texel/src/image/atomic.rs

@@ -5,7 +5,7 @@ use crate::buf::{atomic_buf, AtomicBuffer, AtomicSliceRef};
 use crate::image::{raw::RawImage, IntoPlanesError};
 use crate::layout::{Bytes, Decay, Layout, Mend, PlaneOf, Relocate, SliceLayout, Take, TryMend};
 use crate::texel::{constants::U8, MAX_ALIGN};
-use crate::{Texel, TexelBuffer};
+use crate::{BufferReuseError, Texel, TexelBuffer};
 
 /// A container of allocated bytes, parameterized over the layout.
 ///
@@ -77,6 +77,19 @@ impl<L: Layout> AtomicImage<L> {
             .map_err(Into::into)
     }
 
+    /// Attempt to modify the layout to a new value, without modifying its type.
+    ///
+    /// Returns an `Err` if the layout does not fit the underlying buffer. Otherwise returns `Ok`
+    /// and overwrites the layout accordingly.
+    ///
+    /// TODO: public name and provide a `set_capacity` for `L = Bytes`?
+    pub(crate) fn try_set_layout(&mut self, layout: L) -> Result<(), BufferReuseError>
+    where
+        L: Layout,
+    {
+        self.inner.try_reuse(layout)
+    }
+
     /// Decay into a image with less specific layout.
     ///
     /// See the [`Decay`] trait for an explanation of this operation.
@@ -387,6 +400,19 @@ impl<'data, L> AtomicImageRef<'data, L> {
         Some(self.inner.try_reinterpret(layout).ok()?.into())
     }
 
+    /// Attempt to modify the layout to a new value, without modifying its type.
+    ///
+    /// Returns an `Err` if the layout does not fit the underlying buffer. Otherwise returns `Ok`
+    /// and overwrites the layout accordingly.
+    ///
+    /// TODO: public name and provide a `set_capacity` for `L = Bytes`?
+    pub(crate) fn try_set_layout(&mut self, layout: L) -> Result<(), BufferReuseError>
+    where
+        L: Layout,
+    {
+        self.inner.try_reuse(layout)
+    }
+
     /// Decay into a image with less specific layout.
     ///
     /// See [`AtomicImage::decay`].

texel/src/image/cell.rs

@@ -5,7 +5,7 @@ use crate::buf::{cell_buf, CellBuffer};
 use crate::image::{raw::RawImage, IntoPlanesError};
 use crate::layout::{Bytes, Decay, Layout, Mend, PlaneOf, Relocate, SliceLayout, Take, TryMend};
 use crate::texel::{constants::U8, MAX_ALIGN};
-use crate::{Texel, TexelBuffer};
+use crate::{BufferReuseError, Texel, TexelBuffer};
 use core::cell::Cell;
 
 /// A container of allocated bytes, parameterized over the layout.
@@ -67,6 +67,19 @@ impl<L: Layout> CellImage<L> {
             .map_err(Into::into)
     }
 
+    /// Attempt to modify the layout to a new value, without modifying its type.
+    ///
+    /// Returns an `Err` if the layout does not fit the underlying buffer. Otherwise returns `Ok`
+    /// and overwrites the layout accordingly.
+    ///
+    /// TODO: public name and provide a `set_capacity` for `L = Bytes`?
+    pub(crate) fn try_set_layout(&mut self, layout: L) -> Result<(), BufferReuseError>
+    where
+        L: Layout,
+    {
+        self.inner.try_reuse(layout)
+    }
+
     /// Decay into a image with less specific layout.
     ///
     /// See the [`Decay`] trait for an explanation of this operation.
@@ -370,6 +383,19 @@ impl<'data, L> CellImageRef<'data, L> {
         Some(self.inner.try_reinterpret(layout).ok()?.into())
     }
 
+    /// Attempt to modify the layout to a new value, without modifying its type.
+    ///
+    /// Returns an `Err` if the layout does not fit the underlying buffer. Otherwise returns `Ok`
+    /// and overwrites the layout accordingly.
+    ///
+    /// TODO: public name and provide a `set_capacity` for `L = Bytes`?
+    pub(crate) fn try_set_layout(&mut self, layout: L) -> Result<(), BufferReuseError>
+    where
+        L: Layout,
+    {
+        self.inner.try_reuse(layout)
+    }
+
     /// Decay into a image with less specific layout.
     ///
     /// See [`CellImage::decay`].