P-152: Virtual World Concept Update 165: Planet-sized Terrain: Part 44

I believe I have discovered the cause of this problem.

I am trying to move the terrain (and the player) by 10,000 meters to ensure that both are fixed at the origin.

However, what I failed to realise was that I am trying to move nodes on a sphere. Moving a point by 10,000 meters on a *flat* surface is very simple, however moving the same point on a sphere is very complex. A straight vector subtraction will move the node along the correct axis, but it won’t be aligned with the sphere anymore, it will be either above or below it.

This, I believe, is the issue here. The rendered nodes are rotated at some distance along a sphere, and I need to move them by some distance along that same sphere. I can’t just subtract them, I need to find some solution that moves them along the surface of the sphere itself.

This problem is complex, and in fact, may be impossible to solve in it’s current form.

I have some across some circle and sphere rotation formulas and algorithms, such as Rodrigues’ rotation formula which do what I want, but they require firstly converting to spherical coordinates (from cartesian), performing the rotation, and then converting back to cartesian. Secondly, it rotates by an angle, not a distance, and I would need to calculate this angle.

I will need to do more research before I can solve this.