I've been trying to follow the nehe tutorial on this
http://nehe.gamedev.net/data/lessons/le ... ?lesson=30. I don't understand the formula they are using
Xn dot X = d
Xn, X are vectors and d is a floating point value.
Xn is its normal.
X is a point on its surface.
d is a float representing the distance of the plane along the normal, from the center of the coordinate system.
What I don't understand here is dot, I've done some googling and am assuming he's talking about a dot product.
Essentially a plane represents a half space. So all that we need to define a plane is a 3D point and a normal from that point which is perpendicular to that plane. These two vectors form a plane, ie. if we take for the 3D point the vector (0,0,0) and for the normal (0,1,0) we essentially define a plane across x,z axes. Therefore defining a point and a normal is enough to compute the Vector representation of a plane.
What I think is happening is the plane is spread across the x and y axis with the y always 0, so to make it perpendicular they add 1 to the y axis, would that be correct?
