Schärfig, RandolfHormann, KaiReinhard Koch and Andreas Kolb and Christof Rezk-Salama2014-02-012014-02-012010978-3-905673-79-1https://doi.org/10.2312/PE/VMV/VMV10/211-218In this paper we present a new algorithm for interactively painting onto 3D meshes that exploits recent advances of GPU technology. As the user moves a brush over the 3D mesh, its paint pattern is projected onto the 3D geometry at the current viewing angle and copied to the corresponding region in the object's texture atlas. Both operations are realized on the GPU, with the advantage that all data resides in the fast GPU memory, which in turn leads to high frame rates. A main feature of our approach is the handling of seams. Whenever the brush overlaps two or more patches, this situation is detected and the paint pattern is copied correctly to the corresponding texture charts. In this way the operation of the projection into the texture atlas is completely reduced to a single texture lookup. The performance is independent of the resolution of both the brush and the texture atlas as well as the number of mesh triangles.Categories and Subject Descriptors (according to ACM CCS): I.3.3 [Computer Graphics]: Bitmap and framebuffer operations I.3.7 [Computer Graphics]: Color, shading, shadowing, and texture