Direction of a Triangle (Where is the triangle pointing)

Given 3 2d points that form a triangle, is there a property of a triangle which does not change after any sort of rotation which would help in giving me the direction vector for that triangle. For eg if a triangle is isosceles i can get the direction vector by joining the midpoint of the base to the opposite vertex and I kno开发者_Python百科w which 2 points make the base by looking at the distances. Similar thing can be done for right angle triangles.

Can this be generalized to all triangles?

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It seems that only an isosceles (or near-isosceles) triangle can be pointing in a certain direction.

Calculate the 3 angles of the triangle, the side surrounded by the two identical (or perhapse similar) angles is your base. Then go from there.