Implement as_mut_rows for Buffer

This is to match the existing immutable as_rows method.

1 files changed, 5 insertions, 2 deletions

diff --git a/src/lib.rs b/src/lib.rs
index abcd80f..99c9529 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,7 +2,7 @@ pub use colour::Colour;
 pub use geometry::HasDimensions;
 
 use std::ops::{Deref, DerefMut, Index, IndexMut};
-use std::slice::SliceIndex;
+use std::slice::{ChunksExact, ChunksExactMut, SliceIndex};
 
 pub type Point = geometry::Point<i32>;
 pub type Dimensions = geometry::Dimensions<u32>;
@@ -61,10 +61,13 @@ impl Buffer {
         self.dimensions = dimensions;
     }
 
-    pub fn as_rows(&self) -> std::slice::ChunksExact<Colour> {
+    pub fn as_rows(&self) -> ChunksExact<Colour> {
         self.pixels.chunks_exact(self.dimensions.width as usize)
     }
 
+    pub fn as_mut_rows(&mut self) -> ChunksExactMut<Colour> {
+        self.pixels.chunks_exact_mut(self.dimensions.width as usize)
+    }
 
     pub fn as_u32_slice(&self) -> &[u32] {
         unsafe { std::mem::transmute::<&[Colour], &[u32]>(&self.pixels) }