How to calculate (y) for the player?

Question

Mathematics

I have in 3D space given:
4 points, each of which is known ( x , y , z ) they create a relief, well, or a small square that has a slope
. There is also a player; it is in the range of these points, and the player knows x , z .

It is necessary to calculate the y coordinate for the player using 4 points, naturally for each x , z pair of the player there will be completely different values ​​of y

Answer 1

The plane is defined by just three points. From the given 4, you can take any 3.
Next, see the three-point plane equation .
In general, the plane equation has the form ax + by + cz + d = 0
Get this equation (find a, b, c, d), substitute x, zthe desired point - get ity