bool BasicPrimitiveTests::IntersectingSegmentAgainstPlane(const LineSegment & segment, const Plane & plane, float & rtn_t)
{
/*
Main Idea:
-> Subsitutes line equation into plane to find intersection
-> Tests if intersection is within segment endpoints
Let:
-> Line Segment S:
-> S(t) = A + t * (B-A)
-> for 0 <= t <= 1
-> Plane P:
-> dot(n, X) = d
Solve for "t" of intersection:
-> t = ( d - dot(n, A) / dot(n, B-A) )
-> Return intersection only if:
-> 0 <= t <= 1
*/
rtn_t = ( plane.GetD() - plane.GetNormal().dot(segment.GetPointA()) ) / plane.GetNormal().dot(segment.GetPointB() - segment.GetPointA());
return (rtn_t <= 1.0f && rtn_t >= 0.0f);
}
bool Ray::GetIntersection(const Plane &plane, float &t) const
{
real denom = glm::dot(plane.GetNormal(), mDirection);
if(!denom) {
return false;
}
real numer = -(glm::dot(plane.GetNormal(), mOrigin) + plane.GetD());
t = numer / denom;
if(t >= 0) {
return true;
}
return false;
}