3D Gaussian Splats (3DGS) have proven a versatile rendering primitive, both
for inverse rendering as well as real-time exploration of scenes. In these
applications, coherence across camera frames and multiple views is crucial, be
it for robust convergence of a scene reconstruction or for artifact-free
fly-throughs. Recent work started mitigating artifacts that break multi-view
coherence, including popping artifacts due to inconsistent transparency sorting
and perspective-correct outlines of (2D) splats. At the same time, real-time
requirements forced such implementations to accept compromises in how
transparency of large assemblies of 3D Gaussians is resolved, in turn breaking
coherence in other ways. In our work, we aim at achieving maximum coherence, by
rendering fully perspective-correct 3D Gaussians while using a high-quality
approximation of accurate blending, hybrid transparency, on a per-pixel level,
in order to retain real-time frame rates. Our fast and perspectively accurate
approach for evaluation of 3D Gaussians does not require matrix inversions,
thereby ensuring numerical stability and eliminating the need for special
handling of degenerate splats, and the hybrid transparency formulation for
blending maintains similar quality as fully resolved per-pixel transparencies
at a fraction of the rendering costs. We further show that each of these two
components can be independently integrated into Gaussian splatting systems. In
combination, they achieve up to 2
× higher frame rates, 2
× faster
optimization, and equal or better image quality with fewer rendering artifacts
compared to traditional 3DGS on common benchmarks.