Example-Based Fractured Appearance

Figure 1: Application of our example-based fracturing method on different scenes. Photographs of input fracture patterns are shown in the insets. Left to right: (1) a bathroom tile has been broken, and each fragment can be manipulated separately. (2) Fracture pattern obtained from a ground tile photograph applied on a basin. (3) Sidewalk and curb from a urban scene fractured using the same pattern. (4) A similar but not identical cracked tile created from a photographic exemplar. A common weathering effect is the appearance of cracks due to material fractures. Previous exemplar-based aging and weathering methods have either reused images or sought to replicate observed patterns exactly. We introduce a new approach to exemplar-based modeling that creates weathered patterns on synthetic objects by matching the statistics of fracture patterns in a photograph. We present a user study to determine which statistics are correlated to visual similarity and how they are perceived by the user. We then describe a revised physically-based fracture model capable of producing a wide range of crack patterns at interactive rates. We demonstrate how a Bayesian optimization method can determine the parameters of this model so it can produce a pattern with the same key statistics as an exemplar. Finally, we present results using our approach and various exemplars to produce a variety of fracture effects in synthetic renderings of complex environments. The speed of the fracture simulation allows interactive previews of the fractured results and its application on large scale environments