Re^2: Checking if squares intersect

Actually i came up with the following:

I done this by negation and using the values for the upper left lower right respectively for both sqares.

square #1: upper left= x1,y1 ; lower right= x2,y2
square #2: upper left= x3,y3 ; lower right= x4,y4

return !(x2 < x3 || x1 > x2 || y2 > y3 || y1 < y4)
[download]

Hope my logic is right...can someone confirm?

Thanks,
Total Newbie

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Re^3: Checking if squares intersect by ikegami (Patriarch) on Oct 14, 2009 at 20:36 UTC
x4 is absent, so there's surely an error Adjacent squares don't intersect, so `<` should be `<=` `>` should be `>=` You didn't indicate whether lower "y" values are located higher (that's what you used) or lower (cartesian), so I can't verify the if you are comparing the "y"s properly.	[reply] [d/l] [select]
Re^4: Checking if squares intersect by Anonymous Monk on Oct 14, 2009 at 20:51 UTC
But wouldn't the squares intersect if I changed to < to <= ? Example, if x2 <= x3 then the statement is true if x2 intersects with x3 since x2 is the lower right corner and x3 is the upper left corner. And yes, the x4 is missing, it was a typo.	[reply]
Re^5: Checking if squares intersect by ikegami (Patriarch) on Oct 14, 2009 at 21:13 UTC
No. Adjacent squares don't intersect. `x1 x2=x3 x4 +---------+ y1 \| +---------+ y3 \| \| \| \| \| \| \| \| \| +---------+ \| y2 +---------+ y4` [download]	[reply] [d/l]
Re^6: Checking if squares intersect by QM (Parson) on Oct 15, 2009 at 02:49 UTC
Re^6: Checking if squares intersect by Anonymous Monk on Oct 15, 2009 at 14:43 UTC
Re^7: Checking if squares intersect by ikegami (Patriarch) on Oct 20, 2009 at 01:17 UTC
Re^3: Checking if squares intersect by JavaFan (Canon) on Oct 20, 2009 at 09:38 UTC
Your logic only holds with the additional property that the squares have their edges parallel to the x and y axis. If that isn't the case, your logic fails.	[reply]