I am a beginner in computer graphics but i have solid understanding of linear algebra. I am trying to implement my own forward kinematics for a skeleton. I defined global and local translation vector in child-parent relationships but i am struggling with propagation of rotations from the node n to n+1, n+2 ...
I figured that motion builder uses XYZ rotation order. I created a matrix to transform child vector and "rotate it".
But if i have 3 joints where 1st is parent to 2nd and 2nd is parent to 3rd, if i rotate 1st joint say (10,20,0) locally, i get accurate global position for 2nd and 3rd joint but if i have a local rotation of 2nd joint say (20,0, 0) on top of (10, 20, 0) for the 1st, my 3rd joint's position is wrong. I notice there should be some stacking so that i should probably do (10+20, 20+0, 0+0) for the second rotation but i am not sure why is that the case.
If i could get some links or a book that will address this topic, i would appreciate it. Thanks!
