Hey @NickHardeman. cool! I made it work like you said; using the 009 branch and looking to the rotationExample:
boxVector = pointTo - pointFrom;
posBox = (pointTo + pointFrom) * 0.5;
boxLength = boxVector.length();
boxVector.normalize();
boxSizeY = boxLength - boxesMargin;
boxes.push_back( new ofxBulletBox() );
ofVec3f localBoxAxis( 0, 1, 0 );
// ofVec3f localBoxAxis( 1, 0, 0 );
// ofVec3f localBoxAxis( 0, 0, 1 );
ofQuaternion rotation;
rotation.makeRotate( localBoxAxis, boxVector );
((ofxBulletBox*)boxes[boxes.size()-1])->create( world.world, posBox, rotation, 0.5, boxSizeX, boxSizeY, boxSizeZ);
boxes[boxes.size()-1]->add();
PS: Now, on this tree structure, I am trying to learn how to articulate it (with forces like wind) around nodes between boxes, like a tree / arm elbow / bones. I am using joints to try to limit the movements with the join constraints. I am using ofxBullet just for this, and I am not sure if there is another easier way... Anyway I'll open soon a new thread on the forum and I'll post the link here too! Thanks a lot for your help.