alexs's profile - activity

there are two vector products, the one is the dot product, the other is the cross product. as you are talking about signed area values you probably think about the cross product. when inserting two 2D points into the 3D formula (the normals vector and direction is the measure for the area) then a formula like this is the result:

f([x1,y1],[x2,y2]) = x1 y2 - x2 y1

please watch the _minus_ sign!