The environment simulation is widely used nowadays. Training in many fields such as medicine and architecture heavily depends on virtual reality techniques. Since objects in real life do not have a deterministic shape it is not possible to have a geometric equation that might model them. Convex Hulls (or Convex Envelopes) are a must in such simulations. The need for convex envelopes rises with the intention of having realistic scenes with exact collision detection between objects in the virtual world. In this paper, four algorithms for generating the convex hull are discussed, implemented and compared. The first three algorithms are the Brute Force, the Gift Wrap and the QuickHull algorithm. The fourth one is a hybrid approach that combines the QuickHull and the Gift Wrap algorithms. Simulations were done in the medical environment, and algorithms are tested with the model of 3D wrist and knee bones.