Surface Modeling of a Medical Object Using Triangulation and Marching Cube Algorithm. Medicinisko objektu virsmu modelesana, izmantojot triangulacijas un marsejoso kubu algoritmu

This paper describes two methods that can be used to create three-dimensional surface of a medical object. The first method uses control points and a triangulation algorithm to create three-dimensional surface, the second method is based on the marching cubes algorithm. Then both methods are compared to one another, describing advantages and disadvantages of both methods. The proposed method combines two algorithms: evenly placed control point selection algorithm and a triangulation algorithm. Because the proposed method consists of two algorithms it works in two stages. Firstly control point selection algorithm selects control points on segmented tomograms and then, using the triangulation algorithm the three-dimensional model is built based on these control points. The main advantage of proposed algorithm is that it creates a considerably smoother three- dimensional surface than the marching cube algorithm. Another advantage of the proposed method is that, in similar circumstances it uses almost three times less polygons to describe an object, than the marching cubes algorithm. Marching cube algorithm is one of the algorithms, which is used to create three-dimensional models in medicine. The marching cube algorithm works by dividing the three-dimensional space into cubes of the same size, then the surface that goes through each cube is described, using one of fourteen polygon combinations. The main advantage of the marching cube algorithm is that it doesn't use control points to create a three-dimensional model, because of that, this method can be used to create model of an object of any form. The main disadvantage of the marching cube algorithm is that when creating three-dimensional models based on tomograms there will always be an aliasing effect present on the model.