sideOf: logic
Posted by
Stéphane Ducasse on
Sep 09, 2020; 1:43pm
URL: https://forum.world.st/sideOf-logic-tp5121532.html
Hi all
we have the following method on point and I do not get
why
(0@0) sideOf: (100@100)
>>> #center
sideOf: otherPoint
"Returns #left, #right or #center if the otherPoint lies to the left, right or on the line given by the vector from 0@0 to self"
| side |
side := (self crossProduct: otherPoint) sign.
^ { #right . #center . #left } at: side + 2
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