Spherical Harmonics Architect: Paint View-Dependent Color Into Splats

Most Gaussian Splatting workflows treat spherical harmonics as a training artifact, something the optimization computes and that you accept as-is in the final output. Tijerín Art Studio's new browser-based utility, Spherical Harmonics Architect, gives artists direct control over the view dependent color data encoded in .ply splat files, opening up the ability to paint iridescence, reflective highlights, and directional color effects.

Spherical harmonics, which are often abbreviated SH, are the mathematical basis for how Gaussian Splatting encodes view dependent appearance. Each Gaussian carries a set of SH coefficients that determine how its color shifts as the viewer moves around the scene. This is what makes a shiny surface look different from a matte one, what gives a metallic object its angular highlights, what produces the iridescent color shifts visible in some materials.

During training, the optimizer fits these coefficients to the input images, but the results are only as good as the camera coverage and the quality of the reconstruction. Specular surfaces, thin metallic objects, and anything with sharp directional color response often end up looking flatter than they should, in part because the optimizer converges to something plausible, but not necessarily what the material actually does.

Spherical Harmonics Architect lets artists go back into those coefficients after training, painting iridescence and complex color reflections directly into the .ply file. The tool is framed as a professional grade utility for both artists and researchers, and it runs entirely in the browser. There is no local installation, no GPU driver configuration, no Python environment to manage.

Tijerín Art Studio has been building Gaussian Splatting tools on itch.io for some time. Their lineup includes a Quick Gaussian Splat Editor, a Gaussian Splatting Bridge for format conversion, and a 360 Image Creator.

Spherical Harmonics Architect is available now at their website.