Be careful about using non Integers with Rectangles, too. As with Intervals, I think I remember that some of the API will break.
A new version of Graphics was added to project The Inbox:
http://source.squeak.org/inbox/Graphics-ct.419.mcz
==================== Summary ====================
Name: Graphics-ct.419
Author: ct
Time: 20 September 2019, 7:45:53.388726 pm
UUID: 5deebfce-0321-9645-aebd-0b4bfb428259
Ancestors: Graphics-nice.417
Add Rectangle>>#pointAtFraction:
Example: [(5@5 rect: 10@20) pointAtFraction: 0.5@1] will give you 7.5 @ 20.
dep:feat-ol
=============== Diff against Graphics-nice.417 ===============
Item was added:
+ ----- Method: Rectangle>>pointAtFraction: (in category 'rectangle functions') -----
+ pointAtFraction: relativePoint
+
+ ^ self origin + (self extent * relativePoint)!