Stars don't display over post-processing sky

[shotamatsuda]

Related to e31e2d2

Enabling the depth write for stars partially makes them visible, but it’s unreliable as they are rendered at the camera’s far distance.

[shotamatsuda]

No, this is because irradiance is applied, so the star’s color is treated as albedo. I don’t know what normals the points have.

[shotamatsuda]

It seems that length(viewNormal) > 1.5 reliably distinguishes stars, but don’t understand the source of these normals or　if it’s device dependent.

[shotamatsuda]

But if it’s defined behavior, we’ll need another way to distinguish stars when reconstructNormals is enabled anyways.