Fixing buildings that turned pitch black when facing the moon at night

At night, building faces turned away from the moonlight looked almost black when I faced the moon. After comparing three options, I added 1.25× ambient light and a 0.12 fill moonlight from the opposite side (W3) to the night preset, leaving the day and character brightness alone.

After adding the bright moonlit night (V1) in 144, I was walking around the village and the buildings on the side the moonlight didn't reach came out way too dark. I was on the northeast hill looking southwest, and the moon was in the southwest sky too. So facing the moon, every building face in view was backlit.

I wanted the roof and wall colors to show even on faces turned away from the moonlight. But I decided not to touch the daytime look or the character brightness (C3).

What I built

Now the backlit buildings show their roof colors, timber patterns and walls. On the side that catches moonlight, like the plaza, only the shaded walls got slightly brighter.

I raised the night ambient light by 1.25× (the middle value went from (0.10, 0.13, 0.22) → (0.125, 0.1625, 0.275)). Then I added a fill moonlight shining from the northeast sky, opposite the moon. It's a pale blue (0.55, 0.65, 0.95), intensity 0.12, no shadows. The fill light is also a preset entry, so it transitions along with the time of day. Its day value is 0, so it's off during the day and comes on at 0.12 at night.

I captured the three options with temporary values from the same viewpoint. I even matched the camera and player positions, so the house occlusion handling was under the same conditions too.

Things I thought about

W1: ambient light 1.5×. The backlit faces were still dark, and the moonlit side got evenly brighter all over, which looked flat.
W2: opposite fill moonlight at 0.2. This brought out the wall and roof colors on the backlit faces the best.
W3: ambient light 1.25× + fill 0.12. Halfway between the two. I went with W3. W2 wasn't bad either.
The fill light doesn't reach the character. Its rendering layer is set to Default only. URP reads the value from the additional light data, so I set it in both places. Night character brightness is unchanged.
The fill light is always weaker than the moonlight (0.5). The scene has no main light assigned, so URP picks the brightest directional light as the main light.

Rabbit hole: backlit faces were nearly black

Backlit faces only get ambient light. But night ambient light is about 1/4 of daytime, and moonlight is roughly 0.3–0.45× of sunlight, so the shaded faces sank much deeper than during the day. I fixed it by putting the W3 values above into the night preset.

Next up

If I want it brighter, raise the fill light intensity in the night preset (W2 was 0.2) or the ambient light

Fixing buildings that turned pitch black when facing the moon at night

What I built

Now the backlit buildings show their roof colors, timber patterns and walls. On the side that catches moonlight, like the plaza, only the shaded walls got slightly brighter.

I captured the three options with temporary values from the same viewpoint. I even matched the camera and player positions, so the house occlusion handling was under the same conditions too.

Things I thought about

W1: ambient light 1.5×. The backlit faces were still dark, and the moonlit side got evenly brighter all over, which looked flat.

W2: opposite fill moonlight at 0.2. This brought out the wall and roof colors on the backlit faces the best.

W3: ambient light 1.25× + fill 0.12. Halfway between the two. I went with W3. W2 wasn't bad either.

The fill light doesn't reach the character. Its rendering layer is set to Default only. URP reads the value from the additional light data, so I set it in both places. Night character brightness is unchanged.

The fill light is always weaker than the moonlight (0.5). The scene has no main light assigned, so URP picks the brightest directional light as the main light.