25x25 image at 1x

25x25 image at 2x

25x25 image at 1x, 30x30 image at 2x

25x25 image at 1.5x, 30x30 image at 5x

Invalid tiny scale with fallback to pointer

Over-large image with fallback to pointer

200x200 image at 4x (not over-large in UI pixels)

Non-existent image in image-set with fallback to 25x25 image

Explicit hotspot at (5,3) logical in 1x and 2x

Explicit hotspot at (7,3) logical in 0.7x and 1.4x - should round to nearest integer

Implicit hot-spot at (5,4) physical for 1x and (28,3) physical for 2x