I am working on an object tracking solution that needs to track an object in a scene. I have done research and found that i need to create a 3D map of the keypoints in the scene. So far, i have found a way to collect the keypoints and find the distance from the camera to the point, but how do i use multiple sets of keypoints to map the object in 3D space (like vuforia does). The problem rises when i need to see how much the camera has moved (the angle by which it has moved and its positional movement). How is this solved? Or better yet, can you refer me to a well-documented SLAM code which i can take as a reference in developing my own SLAM based tracking.