How to determine which aspect ratios are closest

Question

Given a rectangular shape S, with aspect ratio sx/sy, and two other rectangular shapes A (with aspect ratio ax/ay) and B (with aspect ratio bx/by) how can I find out which of sh

Answer 1

Looking at the suggestion above, I'm not convinced:

Think on the following example: A = 1:2 B = 2:1 and

targetRatio = 1:1

Clearly both A & B should be equally suitable, but with the comparison of

( 1 - GoalAR/CandiateAR) as suggested,

aspectRatioCandidateA = 0.5 [ 1 : 2 ]

aspectRatioCandidateB = 2 [ 2 : 1 ]

you'd get

closenessScoreA = 1

closenessScoreB = 0.5

The best way to compare aspect ratios is thinking of them as defining an angle:

tan(o) = h/w

o = atan( h/w )

You can then simply compare the difference of the angles now.