how do i determine if two four sided 2D polygon is overlapping?

look at and say to yourself "is this overlapping?"

Intersect their edges, and check if a vertex of A is inside B, and if a vertex of B is inside A.

Cédric

You could follow Cédric''s approach, and use the point-in-polygon link in the forum FAQ to do the inside test.

Forum FAQ


Graham Rhodes
Senior Scientist
Applied Research Associates, Inc.

to check if A vertex is inside a polygon

take a V1 from polygon A and V2 from polygon B

x= V1 +a*(V2-V1)

the line x needs to intersect an edge if it does check the parameter a if it greater zero if so it is inside the polygon
you need to do this for every edge of polygon A