Archived

This topic is now archived and is closed to further replies.

SimDemon

Filling in the plane equation (Ax+By+Cz+D=0)

Recommended Posts

How would I go about filling in the plane equation (Ax+By+Cz+D=0)? I am going to use it for collision detection, but I haven''t figured out how to fill in the equation as you can probably tell. Anyhow, please help me! If thispost = 0 Then GoBack() Else Read() End If

Share this post


Link to post
Share on other sites
Hi

the vector (A,B,C) is the ''normalized normal'' of the plane. D is the distance from the plane to the origin.
So the usual practice is to just hold the normal and D in a plane struct/class. Filling it in goes then like this:


  
void Plane::FromPoints ( Vector v1, Vector v2, Vector v3 )
{
Vector d1, d2;
d1 = v2 - v1;
d2 = v3 - v1;
normal = CrossProduct ( d2, d1 );
normal.Normalize ();
D = -(normal.x*v1.x + normal.y*v1.y + normal.z*v1.z);
}


where v1, v2 and v3 are three arbitrary points on the plane





Runicsoft -- home of my open source Function Parser and more

Share this post


Link to post
Share on other sites
http://astronomy.swin.edu.au/~pbourke/geometry/planeeq/

google, first hit..

google("Plane Equation Ax+By+Cz+D=0");

"take a look around" - limp bizkit
www.google.com

Share this post


Link to post
Share on other sites