Locally restricted blending of Blobtrees

Blobtrees are volume representations particularly useful for models which require smooth blending. When blending is applied to two or more Blobtree models, extra volume will be created in between the two surfaces to form a smooth connection. Although it is easy to apply blending, it is hard to accurately control the resulting shape. More complications arise when the blended objects have large size differences. In this case the influence of the larger objects can overwhelm the influence of the smaller objects. As a result, the shape of the smaller objects can change drastically and the connection between surfaces can appear sharp instead of smooth. This paper presents a locally restricted blend method that solves the blending problem described above. The locally restricted blend locally changes the blending influence of each of the surfaces in order to control blending with the other surfaces. Unlike previous methods, this blend method works with multiple Blobtree surfaces and offers intuitive control over the resulting shape.