Improved silhouette rendering and detection of splat-based models

• Published in: Computers & graphics 2020-12, Vol.93, p.39-50
• Main Authors: Ivo, Rafael Fernandes, Vidal, Creto Augusto, Cavalcante-Neto, Joaquim Bento
• Format: Article
• Language: English
• Subjects: Frequency variation; Image filters; Point-based rendering; Rendering; Sampling; Silhouette; Surface splatting
• ISSN: 0097-8493; 1873-7684
• DOI: 10.1016/j.cag.2020.09.010

•Removal of artifacts on silhouettes in splat-based models.•Efficient silhouette detection of splat-based models on object space.•Silhouette detection can be used for non-photorealistic renderings.•Good trade-off between quality and efficiency of splat-based rendering. [Display omitted] Surface splatting has proven to be a good approach to render point-based models. The technique keeps the simplicity of point based models with a high quality rendering due to local filtering between the samples. However, silhouettes and sharp features are noticed as high frequency variations on image-space. Thus, filtering cannot hide artifacts to appear next to these areas without an explicit approach, mainly on bad sampling conditions as low density of samples. In this paper, we present a new curved splat approach, called here quadric splat, which improves rendering of a model near silhouette and sharp features. These quadric splats may be placed on a surface using any sampling process applying our proposed error metric. We also propose a simple method to detect splats near silhouettes on object-space. This approach allows an efficient silhouette detection on GPUs. Our silhouette detection was applied on a surface splatting pipeline aiming to render quadric splats only where their effect is more noticed, but the technique is independent and can be applied even for non-realistic rendering of splat-based models.