Switch the resolution to be an optional tuple.

render.py

@@ -2,7 +2,7 @@
 
 from pathlib import Path
 from subprocess import run
-from typing import List, Optional
+from typing import List, Optional, Tuple
 
 
 def main() -> None:
@@ -14,8 +14,7 @@ def main() -> None:
                 convert_to_image(
                     source=svg,
                     destination=svg.with_name(f"{svg.stem}-{resolution}.png"),
-                    width=resolution,
-                    height=resolution,
+                    resolution=(resolution, resolution),
                 )
         else:
             convert_to_image(source=svg, destination=svg.with_suffix(".png"))
@@ -24,14 +23,13 @@ def main() -> None:
 def convert_to_image(
     source: Path,
     destination: Path,
-    width: Optional[int] = None,
-    height: Optional[int] = None,
+    resolution: Optional[Tuple[int, int]] = None,
 ) -> None:
     """Convert an SVG to an image with `inkscape`."""
     inkscape_args: List[str] = ["inkscape", str(source), "-o", str(destination)]
 
-    if width is not None and height is not None:
-        inkscape_args.extend(["-w", str(width), "-h", str(height)])
+    if resolution is not None:
+        inkscape_args.extend(["-w", str(resolution[0]), "-h", str(resolution[1])])
 
     run(args=inkscape_args)
     mat2_image(destination)