Intersecting 2D silhouettes: The silhouettes on the left were used to automatically generate the 3D model on the right. Note that the line drawings are not projections of the 3D model, but rather the input that generates the model.
We present a new sketch-based modeling approach in which models are interactively designed by drawing their 2D silhouettes from different views. The core idea of our paper is to limit the input to 2D silhouettes, removing the need to explicitly create or position 3D elements. Arbitrarily complex models can be constructed by assembling them out of parts defined by their silhouettes, which can be combined using CSG operations. We introduce a new simplified algorithm to compute CSG solids that leverages special properties of silhouette cylinders to convert the 3D CSG problem into one that can be handled entirely with 2D operations, making implementation simpler and more robust. We evaluate our approach by modeling a random sampling of man-made objects taken from the words in WordNet, and show that all of the tested man-made objects can be modeled quickly and easily using our approach.
Thanks to Danielle Magrogan for providing many of the models in the range evaluation, and the reviewers of the MIT pre-deadline. Ilya Baran provided helpful discussions and suggestions on the structure of the paper. This work was supported by funding from the MathWorks Fellowship, the Singapore-MIT Gambit Game Lab, and Intel.
3D Modeling with
A User Study Comparing 3D Modeling with Silhouettes and Google SketchUp
3D Modeling with
Silhouettes modeler (2mb) (Win32 only; requires
.NET framework. Includes tutorial.)