Find intersection between two Line3

[Mike_Lee]

Thanks for the link! I did not see this before.

[SOLVED] How to find intersection between two Rays?

Thanks @prisoner849 and @hofk !! The missing piece was to use the dot product (which I still have to get my head around) to get the result I was looking for. the method name could use a better name if anyone uses it. function isPositive( start, end, intersection ){ // all parameters are THREE.Vector3() let v1 = new THREE.Vector3().copy( end ).sub( start ); let v2 = new THREE.Vector3().copy( intersection ).sub( start ); return v1.dot( v2 ) >= 0; } // checks if two line segments will inte…

However, this seems to ignore the Z value. How can I retrieve the Z value for the intersection point as well?