// Returns the point of intersection of a line and a plane
Vector3d LinePlaneIntersectionPoint(Vector3d normal, Vector3d lineStart, Vector3d lineEnd, float distance) {
Vector3d intersectionPoint;
Vector3d lineDirection;
double Numerator = 0.0, Denominator = 0.0, dist = 0.0;
lineDirection = lineEnd - lineStart; // Get the Vector of the line
lineDirection = lineDirection.GetUnit(); // Normalize the line vector
// Use the plane equation with the normal and the line
Numerator = -(normal.x * lineStart.x +
normal.y * lineStart.y +
normal.z * lineStart.z + distance);
Denominator = Vector3d::DotProduct(normal, lineDirection);
if( Denominator == 0.0) // Dont divide by zero
return lineStart;
dist = Numerator / Denominator;
// Travel along the lineDirection by dist and add this to the line start
intersectionPoint.x = (float)(lineStart.x + (lineDirection.x * dist));
intersectionPoint.y = (float)(lineStart.y + (lineDirection.y * dist));
intersectionPoint.z = (float)(lineStart.z + (lineDirection.z * dist));
return intersectionPoint;
}
