% y" F2 N* O2 J+ ` _( n6 m" c& UAs can be seen from the picture, this is the simulation reflecting the intersection. To be specific, when the green circles of array two are moving, the green circles of array one must stop to avoid collision. My point is that how can I make the forwarding green circle stop based on some conditions? Thank you for your tips. + S& {. n# u" L8 l- w
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