This asset tests that linear texture interpolation is performed on linear values, i.e. after sRGB decoding. The test passes when two spheres are rendered with nearly the same color.
-
The first (leftmost) sphere uses only JSON-stored emissive factor of
0.5green. -
The second sphere samples its color as an interpolated value from a
2x1texture. When interpolation happens after sRGB decoding, the final emissive value should also be about0.5green. An example of incorrect interpolation is shown below.
⚠️ WARNING: For technical and historical reasons, some engines — particularly those using WebGL 1.0 — apply sRGB decoding in the fragment shader. Such engines will "fail" this test, which is designed specifically to highlight a difference that is generally quite subtle. Modern APIs like WebGL 2.0 and WebGPU provide effective ways to avoid this issue.
Public domain (CC0)