The aim of this thesis is to implement an application that is able to build stylized contours to any 3D model using screen-space analysis. To achieve the wished results, the accurate selection of lines that are considered important from a given angle and distance is of key importance. Furthermore, it’s necessary to guarantee the coherence of style and line positions in time, because their incoherence creates an unpleasant, vibrating effect during animation. Finally, the solution is designed to run real-time; therefore the used algorithms have to be implemented in a time-efficient way.
The implemented program should create an image that resembles a hand-drawn picture for every frame of an animation. When analyzing an image, actually the three dimensional model is inspected from a given angle of view. Defining consistent lines is not an easy task. Lines have to be consistent in two aspects. First of all, it is not acceptable if the pixels are not exactly on the right position for every subsequent frame, because that results in the mentioned vibrating effect. Secondly, we have to create continuous lines that appear and disappear gradually when the distance between the object and camera changes. Finally, care has to be taken when implementing the noise used for the stylized silhouettes; noise should not be attached to the screen, but the lines.