textium::texture: implement a rotated patch method for the packer

textium/src/texture.rs

@@ -30,6 +30,22 @@ pub trait Buffer2d: Sized {
             }
         }
     }
+
+    fn patch_rotated<B>(&mut self, x: usize, y: usize, buf: &B)
+        where B: Buffer2d<Pixel=Self::Pixel>
+    {
+        let (w, h) = buf.dimensions();
+
+        // TODO: can this be optimized by performing an unsafe memcpy of some sort?
+        for sy in 0..h {
+            for sx in 0..w {
+                match buf.get(sx, sy) {
+                    Some(v) => self.set(x+h-sy-1, y+sy, v),
+                    _ => (),
+                }
+            }
+        }
+    }
 }
 
 pub trait ResizeableBuffer2d: Buffer2d {