A square tile collides with another square tile. The bartender says...
I have:
you have to model your square to capture the orientation too , just with (x,y,height) of the square , orientation i mean whether its in first ,second ,third of fourth quadrant , may be by modeling all four corner vertices of square .
then you need to determine , all the four vectors that make this square
find cosine between the 2D Vector you have with each side of square for example if cosine of given side and 2D Vector is 1 , then both are orthogonal or 0 they are perpendicular , any other value would fall in between
or any other vector algebra tricks on how you want to determine/define your collision !