diff --git a/CHANGELOG.md b/CHANGELOG.md
index 81eda76..7feaa88 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,6 +32,7 @@
 - `X11Surface` now has an explicit `submit` function
 - `X11Surface` is now multi-window capable.
 - `Renderer::clear` now expects a second argument to optionally only clear parts of the buffer/surface
+- `Transform::transform_size` now takes a `Size` instead of two `u32`
 
 ### Additions
 
diff --git a/src/backend/renderer/mod.rs b/src/backend/renderer/mod.rs
index f2c8ee6..2711e22 100644
--- a/src/backend/renderer/mod.rs
+++ b/src/backend/renderer/mod.rs
@@ -10,7 +10,7 @@
 use std::collections::HashSet;
 use std::error::Error;
 
-use crate::utils::{Buffer, Physical, Point, Rectangle, Size};
+use crate::utils::{Buffer, Coordinate, Physical, Point, Rectangle, Size};
 
 #[cfg(feature = "wayland_frontend")]
 use crate::wayland::compositor::SurfaceData;
@@ -94,15 +94,15 @@ impl Transform {
     }
 
     /// Transformed size after applying this transformation.
-    pub fn transform_size(&self, width: u32, height: u32) -> (u32, u32) {
+    pub fn transform_size<N: Coordinate, Kind>(&self, size: Size<N, Kind>) -> Size<N, Kind> {
         if *self == Transform::_90
             || *self == Transform::_270
             || *self == Transform::Flipped90
             || *self == Transform::Flipped270
         {
-            (height, width)
+            (size.h, size.w).into()
         } else {
-            (width, height)
+            size
         }
     }
 }