diff --git a/draw.go b/draw.go
index 3b29a85..af9706b 100644
--- a/draw.go
+++ b/draw.go
@@ -6,6 +6,7 @@ import "image/draw"
 import "image/color"
 import "golang.org/x/image/font"
 import "golang.org/x/image/math/fixed"
+import "git.tebibyte.media/tomo/typeset/internal"
 
 // Draw draws the contents of a TypeSetter to an image at the given offset. It
 // returns a rectangle containing all pixels in the image that were updated.
@@ -63,11 +64,11 @@ func DrawBounds (destination draw.Image, setter *TypeSetter, offset fixed.Point2
 	layoutBounds      := setter.LayoutBounds()
 	
 	minimum     := setter.MinimumSize()
-	minimumRect := roundRect(fixed.Rectangle26_6 { Max: minimum }.Add(offset).Add(layoutBounds.Min))
-	drawRectangleOutline(destination, minimumRect, green)
+	minimumRect := internal.RoundRect(fixed.Rectangle26_6 { Max: minimum }.Add(offset).Add(layoutBounds.Min))
+	internal.DrawRectangleOutline(destination, minimumRect, green)
 	
-	drawRectangleOutline(destination, roundRect(layoutBoundsSpace.Add(offset)), blue)
-	drawRectangleOutline(destination, roundRect(layoutBounds.Add(offset)), red)
+	internal.DrawRectangleOutline(destination, internal.RoundRect(layoutBoundsSpace.Add(offset)), blue)
+	internal.DrawRectangleOutline(destination, internal.RoundRect(layoutBounds.Add(offset)), red)
 }
 
 func drawTofu (
@@ -78,29 +79,8 @@ func drawTofu (
 	col         color.Color,
 ) {
 	bounds, _ := tofuBounds(face)
-	rectBounds := roundRect(bounds).Add(image.Pt (
+	rectBounds := internal.RoundRect(bounds).Add(image.Pt (
 		position.X.Round(),
 		position.Y.Round()))
-	drawRectangleOutline(destination, rectBounds, col)
-}
-
-func drawRectangleOutline (destination draw.Image, bounds image.Rectangle, col color.Color) {
-	for x := bounds.Min.X; x < bounds.Max.X; x ++ {
-		destination.Set(x, bounds.Min.Y, col)
-	}
-	for y := bounds.Min.Y; y < bounds.Max.Y; y ++ {
-		destination.Set(bounds.Min.X, y, col)
-		destination.Set(bounds.Max.X - 1, y, col)
-	}
-	for x := bounds.Min.X; x < bounds.Max.X; x ++ {
-		destination.Set(x, bounds.Max.Y - 1, col)
-	}
-}
-
-func roundRect (rectangle fixed.Rectangle26_6) image.Rectangle {
-	return image.Rect (
-		rectangle.Min.X.Round(),
-		rectangle.Min.Y.Round(),
-		rectangle.Max.X.Round(),
-		rectangle.Max.Y.Round())
+	internal.DrawRectangleOutline(destination, rectBounds, col)
 }
diff --git a/internal/draw.go b/internal/draw.go
new file mode 100644
index 0000000..9bf9502
--- /dev/null
+++ b/internal/draw.go
@@ -0,0 +1,27 @@
+package internal
+
+import "image"
+import "image/draw"
+import "image/color"
+import "golang.org/x/image/math/fixed"
+
+func DrawRectangleOutline (destination draw.Image, bounds image.Rectangle, col color.Color) {
+	for x := bounds.Min.X; x < bounds.Max.X; x ++ {
+		destination.Set(x, bounds.Min.Y, col)
+	}
+	for y := bounds.Min.Y; y < bounds.Max.Y; y ++ {
+		destination.Set(bounds.Min.X, y, col)
+		destination.Set(bounds.Max.X - 1, y, col)
+	}
+	for x := bounds.Min.X; x < bounds.Max.X; x ++ {
+		destination.Set(x, bounds.Max.Y - 1, col)
+	}
+}
+
+func RoundRect (rectangle fixed.Rectangle26_6) image.Rectangle {
+	return image.Rect (
+		rectangle.Min.X.Round(),
+		rectangle.Min.Y.Round(),
+		rectangle.Max.X.Round(),
+		rectangle.Max.Y.Round())
+}