   [DX10] Rotation matrix construction issues.
  I rendering a sphere with the usual rotation, scaling and translation.It is not that I don't understand rotation but apparently not enough.I want to place a flat object, say a disk on any given vertex and want it to be aligned such that the vertex normal is perpendicular to it's surface.I have managed to position the disk regardless of the spheres position/scale and/or rotation. but I can't get the rotation of the disk right.So what I'm looking for is how to construct a rotation matrix for my disk.I have looked into billboarding and I understand that this is a similar situation but somehow I am still unable to apply it.Any hints are appreciated.   
Quote:Original post by AnnoyedI rendering a sphere with the usual rotation, scaling and translation.It is not that I don't understand rotation but apparently not enough.I want to place a flat object, say a disk on any given vertex and want it to be aligned such that the vertex normal is perpendicular to it's surface.I have managed to position the disk regardless of the spheres position/scale and/or rotation. but I can't get the rotation of the disk right.So what I'm looking for is how to construct a rotation matrix for my disk.I have looked into billboarding and I understand that this is a similar situation but somehow I am still unable to apply it.Any hints are appreciated.This gets discussed a lot here - try searching the forum archives for 'align to normal' or 'align to vector', and you should be able to find some good explanations and code examples.If that doesn't clear things up, perhaps you could describe what you've tried so far and where you're getting hung up.   ;  Thank you, this was a issue of asking the right question.Your search hints did the job.   