How to check the order of mesh hit by a ray

[ParvGuptaSpCT]

Hello Devs,

I'm working with a mesh with high-convexity faces. as shown

in my application i have cut the mesh using the geodesic path
result:

I'm using a ray rayMeshIntersect from mesh bounding box center towards a point 50 units above the center, the aim was to identify which component is above the other, the problem in this case the starting point of the ray lies outside the mesh hence no intersection with the ray, I can not just check the z-value to identify because of other edge cases.

I have also tried reversing the direction of the ray but now it is giving intersection with both the mesh

is it possible if i can cast a ray outside the meh towards the mesh center and check the order in which the mesh intersected with the ray?

thanks

[Grantim]

Hello!

You can just compare rayIntersectoinResult.distanceAlongLine from both intersections to determine which one is closer to origin of the ray

[ParvGuptaSpCT]

got it
Thanks!!

[Grantim]

Another way to find which part is upper is to compare hole normal with PlusZ direction:

looksUp =  mm.dot( -mesh.holeDirArea( mesh.topology.findHoleRepresentiveEdges()[0] ), mm.Vector3d(0,0,1) ) > 0.0