How to do ray plane intersection?
c++, raycasting, raytracing
Solution
As wonce commented, you want to also allow the denominator to be negative, otherwise you will miss intersections with the front face of your plane. However, you still want a test to avoid a division by zero, which would indicate the ray being parallel to the plane. You also have a superfluous negation in your computation of `t`. Overall, it should look like this:
float denom = normal.dot(ray.direction);
if (abs(denom) > 0.0001f) // your favorite epsilon
{
float t = (center - ray.origin).dot(normal) / denom;
if (t >= 0) return true; // you might want to allow an epsilon here too
}
return false;
Problem
How do I calculate the intersection between a ray and a plane? Code This produces the wrong results. ``` float denom = normal.dot(ray.direction); if (denom > 0) { float t = -((center - ray.origin).dot(normal)) / denom; if (t >= 0) { rec.tHit = t; rec.anyHit = true; computeSurfaceHitFields(ray, rec); return true; } } ``` Parameters `ray` represents the ray object. `ray.direction` is the direction vector. `ray.origin` is the origin vector. `rec` represents the result object. `rec.tHit` is the value of the hit. `rec.anyHit` is a boolean. My function has access to the plane: `center` and `normal` defines the plane