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Although intuitive, sketching a closed 3D shape directly in an immersive environment results in an unordered set of arbitrary
strokes, which can be difficult to assemble into a closed surface. We tackle this challenge by introducing VRSurf, a surfacing
method inspired by a balloon inflation metaphor: Seeded in the sparse scaffold formed by the strokes, a smooth, closed surface
is inflated to progressively interpolate the input strokes, sampled into lists of points. These are treated in a divide-and-conquer
manner, which allows for automatically triggering some additional balloon inflation followed by fusion if the current inflation
stops due to a detected concavity. While the input strokes are intended to belong to the same smooth 3D shape, our method
is robust to coarse VR input and does not require strokes to be aligned. We simply avoid intersecting strokes that might give
an inconsistent surface position due to the roughness of the VR drawing. Moreover, no additional topological information is
required, and all the user needs to do is specify the initial seeding location for the first balloon. The results show that VRsurf
can efficiently generate smooth surfaces that interpolate sparse sets of unoriented strokes. Validation includes a side-by-side
comparison with other reconstruction methods on the same input VR sketch. We also check that our solution matches the user’s
intent by applying it to strokes that were sketched on an existing 3D shape and comparing what we get to the original one.
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