A Non-Photorealistic Rendering Technique for Art-directed Hatching of 3D Point Clouds

Point clouds or point-based geometry of varying density can nowadays be easily acquired using LiDAR cameras or modern smartphones with LiDAR sensors. We demonstrate how this data can be used directly to create novel artistic digital content using Non-Photorealistic Rendering techniques. We introduce a GPU-based technique for art-directable NPR rendering of 3D point clouds at interactive frame-rates. The technique uses either a subset or all of the points to generate oriented, sketchy strokes by taking local curvature and normal information into account. It uses X-Toon textures as part of its parameterization, supports hatching and cross hatching, and is inherently temporal coherent with respect to virtual camera movements. This introduces significant artistic freedom that is underlined by our results, which show that a variety of different sketchy styles such as colored crayons, pencil, pointillism, wax crayons, blue print, and chalk-drawings can be achieved on a wide spectrum of point clouds, i.e., covering 3D polygonal meshes as well as iPad-based LiDAR scans.