Bai, YaoyiHasan, MilošYan, Ling-QiHaines, EricGarces, Elena2024-06-252024-06-252024978-3-03868-262-21727-3463https://doi.org/10.2312/sr.20241157https://diglib.eg.org/handle/10.2312/sr20241157Interpolation between objects of varying dimensionality is a common task in computer graphics; however, high-quality dynamic natural interpolation for appearance remains scarce. In this paper, we propose a blending framework for general appearances that can be integrated into renderers without modifying the rendering pipeline. For natural interpolation calculations, we use the mathematical tool optimal transport (OT), known for its promising blending quality. Although recent advancements in OT theory have improved computational performance, integrating runtime OT calculations into the path tracing rendering pipeline compromises algorithm efficiency and increases storage requirements. To address this, we propose a novel solution that precomputes appearances into a proxy distribution and introduces a hierarchical query structure. This enables efficient online point or range data querying, allowing for the generation or retrieval of large data sets as needed. Additionally, the proxy and hierarchical query structure facilitate multi-way barycenter computation. With this efficient query structure and barycentric calculation, we demonstrate several applications of our method, including 2D and 3D interpolation, as well as isotropic BRDF interpolation.Attribution 4.0 International LicenseKeywords: appearance synthesis, proxy, query CCS Concepts: Computing methodologies -> RenderingKeywordsappearance synthesisproxyquery CCS ConceptsComputing methodologies> Rendering10.2312/sr.2024115711 pages