I'm working on a 3D simulation, and I need to find two vectors: 1. from the viewer to a point on a water plane, and 2. from the point on the water plane to the sun. What I know is that I can use reflection math to reflect a given vector, but I do not have a vector to reflect, which is my problem.
- I have the X,Y,Z viewer point (lets say on a hill, Y = 40), and the X,Y,Z sun point.
- I have the water line (at a given height [like Y=20]). Up (plane normal) is 0,1,0.
Given two points and a plane how do I find the point on the plane where the reflection occurs? Once I find that point I can get the other vectors (that's the easy part). I imagine that if I can deduce the angle on one side I can easily use geometry to reflect it, but I'm struggling with finding that angle, or even if that is the right approach to getting a point on the plane, thanks.