Y value of a point on a quad
I am having trouble figuring the height of a point on any given quad. Is there some way of calculating this using the coordinates of the 4 corners?
I have the 4 coordinates of the corners, and the x and z values of the point on the quad..I want to find the y value of that point.
The quad is in 3d space, and is planar.
I think I'm having trouble posting, not sure but my replies arent showing up.
I have the 4 coordinates of the corners, and the x and z values of the point on the quad..I want to find the y value of that point.
The quad is in 3d space, and is planar.
I think I'm having trouble posting, not sure but my replies arent showing up.
Yes.
How many dimensions are we working in? (It's a bit easier in 2D than 3D). If in 3D, are we guaranteed that the quad is actually planar, and that the point is in the same plane?
How many dimensions are we working in? (It's a bit easier in 2D than 3D). If in 3D, are we guaranteed that the quad is actually planar, and that the point is in the same plane?
what information are you starting with and what do you want to end up with?
Sir, e^iÏ€ + 1 = 0, hence God exists; reply!
The quad is in 3 dimensions.
It is planar.
I have the 4 corners of the quad, and the x and z values of some point on that quad..what I want is the y value of that point on the quad.
It is planar.
I have the 4 corners of the quad, and the x and z values of some point on that quad..what I want is the y value of that point on the quad.
if the vertices of the quad are A, B, C, D then (AB) x (DB) gives you the quad's plane's normal, and a vertical line through the point is (X,0,Z) + k(0,1,0). Then you can do a standard lineplane intersection.
More simply than the plane/line thing, just plug x & z straight into the plane equation, and solve for y (which is the only remaining unknown).
Possibly Related Threads...
Thread:  Author  Replies:  Views:  Last Post  
quick opengl 2d quad question  dave05  2  4,078 
Jun 9, 2005 06:09 PM Last Post: arekkusu 

Quad Vertex Array Woes  WakingJohn  1  2,756 
Apr 9, 2005 07:55 PM Last Post: WakingJohn 

Turn a Quad into particles  MACnus  10  7,792 
Feb 6, 2005 09:10 AM Last Post: Duane 

Quad CollisionDetection  Duane  5  6,144 
Jan 18, 2005 01:42 PM Last Post: Duane 

Alpha value on textured quad  monteboyd  5  4,968 
Jun 29, 2002 04:36 AM Last Post: inio 