SCNHitResult - draw line to hit point

Question

I would like to draw a line (or a very thin SCNCylinder) that traces the ray which was used to determine an SCNHitResult which I got from an SCNView using its hitTest:options method.

 NSArray *hitResults = [self.skView hitTest:point options:nil];

My problem is that I need two points to construct this line: The origin (which is the SCNScene's pointOfView.position) and the point where the ray hit the first object (of which I don't know how to get the position).

Is there a way to get the position of the first hit SCNGeometry from the hit test? I have been trying the unprojectPoint: method of the SCNView to no avail. Thanks for any pointers.

Answer 1

Check this code

    NSArray *hitResults = [self.skView hitTest:point options:nil];
    // check that we clicked on at least one object
    if ([hitResults count] > 0) {
        // retrieved the first clicked object
        SCNHitTestResult * result = [hitResults firstObject];
        result.localCoordinates //position relative to local in V3
        result.worldCoordinates //position relative to world in V3
    }

I hope this helps you