Automatic paper pop-up design

Abstract

We present a computational method capable of designing complex Origamic Architecture (OA) report pop-ups that closely depict the given 3D objects, which are input as digital 3D models. OA is a form of paper craft involving paper cutting and folding to produce pop-up models of objects. Our method targets a common type of OA in which each pop-up must be one single connected sheet of paper, and all the folds must be 90 degrees. These strict geometric requirements make the pop-up design difficult for most people.

Our method fully automates the design process, using raster graphics rendering and 2D image processing to produce pop-up designs for the input models. We render an orthographic view of the model from a view direction 45 degrees above the horizon to obtain a depth map. The rendering automatically removes irrelevant geometry, and the use of the 45-degree view direction offers many critical benefits. The depth map is then transformed to a valid pop-up plan using only one single conversion rule that can be applied indiscriminately regardless of the input surface types. The conversion consists of a depth quantization step and a structure correction step, and together they produce a valid 2D OA plan that can be cut and folded to construct the pop-up. Our image-domain approach avoids direct 3D geometry processing of the input model, and thus averts many potential degeneracy and robustness issues.

Very little input is required from the user. The user can control the degree of intricacy of the pop-up by specifying a minimum gap size between cuts and folds. Even though very limited aesthetic control is provided, in many cases, our system has been successful in producing valid, beautiful and intricate pop-ups for complex objects.