Question about planes

sorry but I afraid you can't draw a plane because it's area is infinite...
maybe you can draw a large rectangle instead.

ok how do i do that?

MS Paint?

Or you could tell us what language/platform you would like to do this in [smile]

c++ opengl

ax + by + cz + d = 0

gives

z = (-ax - by - d) / c

Pick 4 points in the x-y-plane and use the above equation to calculate the four corresponding z-values for the plane on that points, create a quad from those points and render and there you have part of a plane.

To render the normal just pick a point on the plane and draw a line from that point to a point on the line formed by that point and the normal vector.

thank you

Quote:

Original post by Enselic ax + by + cz + d = 0 gives z = (-ax - by - d) / c

Just for completion: Obviously there is a need of case distinction, since the 2nd formula doesn't work for planes where c is 0 or at least near to 0. You may use the maximum of the absolute |a|, |b|, and |c| to determine which case best to use, like so:

max(|a|,|b|,|c|) == |a| => x = (- by - cz - d) / a
max(|a|,|b|,|c|) == |b| => y = (- ax - cz - d) / b
max(|a|,|b|,|c|) == |c| => z = (- ax - by - d) / c