📖 Documentation • 🎬 Video • ✉️ Support • 🌐 havoila.com
A living sky for URP: physically based light, volumetric clouds and real weather, from sunrise to the Milky Way.
Drop-In Sky & Weather computes the sky from the air itself: the blue of the day, white horizons, orange and red sunsets, the blue hour, then a night with the real stars in their real places. Volumetric clouds drift and change shape with the wind, sweep their shadows over your world and let shafts of light through. Rain and snow fall from those clouds, lightning strikes, and the ground gets wet or white.
Add it to a URP scene and it becomes your skybox and lights your scene. No renderer feature to add and nothing to bake.
✅ Physically based: sky, fog and scene lighting from one model of the air
✅ Volumetric clouds: from fair-weather cumulus to anvil-topped storms, with shadows and light shafts
✅ Real weather: rain, snow, lightning, rainbows, wet and snowy ground
✅ Day and night: the real sun, moon, stars and Milky Way for any place and date
🌅 A PHYSICALLY BASED SKY
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- The real sky's colours. They come from the air, the haze and the ozone (after Hillaire, 2020): a blue day, orange and red sunsets and the blue hour all follow the sun's height. Change the air to make other worlds.
- Atmospheric fog. The same air fogs your scene: distant hills fade into the sky's colours, with mist near the ground and shafts of light behind trees and walls. It works with transparent objects, MSAA and Unity's own shaders.
- Live scene lighting. It follows the sky as it is now, clouds included: ambient light, reflections and the sun's colour, every frame, with nothing to bake.
- Night exposure. URP has no auto-exposure, so the sky adds one. Evenings and nights stay readable, with a blue shift deep in the night.
- Soft shadows (optional). The sun's and the moon's shadows as soft as real ones: sharp where an object meets the ground, wider the farther they fall.
☁️ VOLUMETRIC CLOUDS
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- Every kind of cloud. Fair-weather cumulus, flat layers and towering storm clouds that spread into anvils, with silver linings and light scattered inside them.
- Alive in the wind. They drift and change shape as they go, and their shadows sweep over the scene while shafts of sunlight fall between them.
- Shadows from far away. At sunrise and sunset, mountains kilometres away cast their shadows into the air and onto your scene.
- High cirrus. They catch the last light of sunset, and a veil of them rings the sun and the moon with a 22° halo and sun dogs.
- Cloud Areas. Place clouds, or clear the sky, over the regions you choose.
⛈️ WEATHER
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- Presets and cycles. Nine presets, from clear to stormy, applied at once or blended over time, and a weather cycle that changes the weather by itself, the same way every time for the same clock.
- Rain and snow. Rain curtains hang under distant clouds, with a rainbow where a low sun lights them. Rain and snow fall around the camera, only under the clouds, stop under roofs and splash where they land, on moving objects too.
- Lightning. It flashes inside the clouds, lights the scene and strikes the ground, with thunder from your own sound clips.
- Wet and snowy ground. The ground gets wet and white, and your materials can show it: Shader Graph sub graphs and an HLSL include are included.
🌌 DAY AND NIGHT
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- The real sky, anywhere. Set the time, the date and the place, or follow the computer's clock: the sun, the moon with its phases, the stars and the Milky Way are where they really are.
- Night wonders. Eclipses come on their real dates. Cities glow on the horizon and under the clouds, auroras fold and ripple towards the pole, and shooting stars, satellites and airliners cross the night.
🎬 MADE FOR GAMES AND FILMS
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- A shared clock. Drive it from your network time or from Timeline (tracks included): the same sky for every player and for every scrub.
- Events and saves. Events for sunrise, sunset and each hour, and save and load of the whole sky.
- Recording and HDRI. A recording mode for clean frames with Unity Recorder, and HDRI export (an EXR panorama) for other renderers or baked lighting.
- Open data. Published values (the environment, the fog, the cloud shadows, the weather) that your other assets can read.
🛠️ DROP-IN WORKFLOW
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- One component. From Tools > Havoila Studio > Drop-In Sky > Create Sky: it becomes your skybox and lights the scene.
- One Inspector. For everything, with a Scene view overlay for the time, the preset and the weather.
- Full source. C# and HLSL.
⚡ PERFORMANCE
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- Measured cost. About 1.2 ms (Low), 1.8 ms (Medium) or 3.4 ms (High) of GPU time at 1920 × 1080 on an RTX 5080 in the demo, with the clouds, the fog, the scene lighting and the far shadows included, and about 0.2 ms of the main thread.
📦 INCLUDED
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- A 12 × 8 km park. Forests, lakes, a desert, a highway and its gas station, a lake house and seaplanes, deer and birds, with a panel to change the time and the weather in Play mode.
- Ready to use. Nine presets, Timeline tracks, and sub graphs for wet and snowy materials.
- Documentation. As a PDF and online.
✔️ COMPATIBILITY
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- Unity 6.3 LTS or newer. URP 17 or newer (Render Graph). Tested with the Forward and Forward+ renderers.
- Desktop and consoles. Windows, macOS, Linux and consoles: compute shaders are required. Tested on Windows (DirectX 12).
- PC VR. Single-pass instanced and multi-pass.
- One setting. Turn on Light Cookies in the URP asset for the cloud shadows; there is nothing else to set.
- Pairs with Drop-In Water. Sold separately, not required: the water reflects the live sky and clouds, takes the fog, and ripples under the rain.
🚧 GOOD TO KNOW
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- Below the clouds. Cameras stay below them: flying through or above them is not supported.
- Platforms. No mobile or WebGL in this version, and no standalone (Android) VR headsets.
- One sky per scene. Rain stops under colliders only.
- Thunder sounds. Bring your own clips: none are included.
💬 SUPPORT
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Questions or issues? Write to support@havoila.com. Tools > Havoila Studio > Drop-In Sky > Contact Support opens an email with your versions filled in.
