Clouds¶
The Clouds module draws a cloud shadow mask every frame and hands it to the sun as a light cookie. Every lit surface in URP picks it up: no geometry, no extra shadow pass and no cascade seam.
The clouds are anchored in the world, over a Shadow Area square centred on the
Clouds object:
- Shadows fade out over the square's outer tenth. Beyond it there are none.
- The mask projects down onto a ground plane at the
Cloudsobject's height, so keep that object at ground level. - A day cycle that moves the sun does not drag the clouds; only the wind moves them.
The sky draws the same cloud field Sky Height metres above the Clouds object. Sky
Height only changes how large and fast the clouds look overhead. Their shadows fall
straight beneath them either way.
Which light gets the cookie: Sun Light Override if set, else RenderSettings.sun,
else the first active directional light in the scene. If that light already had a cookie,
Fable restores it when cloud shadows are switched off.
SHADOWS¶
| Setting | What it does | Default | Shipped preset |
|---|---|---|---|
| Cast Shadows | Cast cloud shadows through the sun's light cookie. The sky still draws the clouds with this off. | On | On |
| Tile Size (m) | Distance over which the cloud pattern repeats. Feature size is roughly Tile Size / Cells. | 250 | 300 |
| Shadow Area (m) | Side of the square that receives shadows, centred on the Clouds object. The mask's resolution is spread over it, so keep it no bigger than the level needs. |
600 | 600 |
| Strength | How dark the shadows get. 0 is none, 1 blocks the direct sun. | 0.55 | 0.52 |
| Coverage | Fraction of the ground under cloud. | 0.45 | 0.605 |
| Softness | Edge falloff. Low values give hard toon edges. | 0.06 | 0.015 |
| Resolution (MORE) | Texels across the Shadow Area: 256, 512, 1024 or 2048. Over 600 m, 512 is about 1.2 m a texel. Memory is 4 bytes a texel, 16 MB at 2048. | 512 | 1024 |
| Sun Light Override (MORE) | An explicit sun. Stored on the module, because a settings asset cannot hold a scene object. | None |
SHAPE¶
Two noise layers scroll at different scales and directions. The beat between them is what reads as drifting cloud rather than sliding wallpaper.
| Setting | What it does | Default | Shipped preset |
|---|---|---|---|
| Layer 1 Cells | Cells across one tile for the large, slow layer. Lower gives bigger masses. | 4 | 15 |
| Layer 2 Cells | Cells across one tile for the faster layer. | 6 | 7 |
| Shape Blend | 0 gives billowy Perlin masses, 1 chunky Voronoi clumps. | 1 | 0.303 |
| Sky Height (m) | Height of the cloud layer the sky draws, above the Clouds object. |
250 | 250 |
| Voronoi Jitter (MORE) | How far Voronoi cell centres wander. Higher gives more irregular clumps. | 0.14 | 1 |
| Seed (MORE) | Changes the pattern. | 0 | 0 |
WIND¶
| Setting | What it does | Default | Shipped preset |
|---|---|---|---|
| Follow Global Wind | Drift along the Wind module's direction. | On | On |
| Wind Direction | Drift direction as an (X, Z) vector, shown when Follow Global Wind is off. | (1, 0.5) | (-1, -0.5) |
| Speed Multiplier | |||
| Scales the drift. At 1 the clouds travel 1.5 m/s downwind; the second layer crosses at half that speed. | 1 | 0.25 |