📖 Documentation • 🎬 Video • ✉️ Support • 🌐 havoila.com
Realistic oceans, lakes and rivers for URP, and water your gameplay can actually use.
Drop-In Water simulates water the way it behaves: waves raised by the wind and the swell, rising and breaking over reefs, running up the beach and draining back down. It lights that water from how sunlight travels through it, from turquoise shallows to the deep blue open sea, above and below the surface. And because a game needs more than a pretty surface, the very same waves lift your boats, answer your code instantly and stay identical on every client of a multiplayer game.
Add an Ocean to a URP scene and press Play. No renderer feature, no URP settings, nothing to bake to get started.
✅ Gameplay-ready: instant CPU water queries, buoyancy, multiplayer-safe waves
✅ Living coastlines: surf, breaking bores, swash, spray and wet sand
✅ Physically based light: absorption, refraction, reflections, caustics, light shafts
✅ True drop-in: one component, no setup, every effect switchable
🎮 MADE FOR GAMEPLAY
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- Instant water queries. Height, normal and velocity anywhere, from a CPU copy of the exact waves the GPU draws. No GPU readback, no frame of delay: call it in FixedUpdate, batch thousands per frame in Burst jobs, or run it on a headless server with no GPU at all.
- Buoyancy that feels right. Add a Floating Body to any Rigidbody: Archimedes' force and water drag, every floating body in one Burst job per physics step. Automated tests check the floating height against Archimedes' exact draft.
- The same sea for every player. The waves depend only on the settings, the seed and the time. Share the clock and every client sees, and floats on, the same sea. A network clock sample is included.
- Wakes and ripples. Boats, swimmers and splashes push the water: rings, bow waves and true Kelvin wakes, every wavelength travelling at its real speed, with foam where the water churns.
- Ready to drive. The demo's rowboat controller and autopilot are a starting point for your own boats.
🌊 WAVES FROM THE WEATHER
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- Wind and swell. FFT ocean from wind speed, direction and fetch (JONSWAP spectrum) plus a separate swell: from a glassy calm to a gale, with the wave heights and periods oceanography predicts.
- Every scale. Four cascades, from kilometre-long swells to centimetre ripples, with sharp crests and whitecaps that gather in the gusts.
- To the horizon. An infinite ocean: a camera-centred level-of-detail mesh with no seams and no popping.
- Loops on demand. Waves that repeat exactly after a period you choose, for networking, replays and cutscenes.
🏝️ LIVING SHORELINES
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Bake your terrain once and the coast comes alive:
- Surf. Waves feel the bottom: they shrink, steepen and break over reefs and sandbars.
- Swash. Each wave rolls in as a breaking bore, runs up the beach, slows at the top, then drains back, pulling its foam into streaks.
- Wet sand. The sand darkens where the water reached and shines as it drains, and a line of foam marks each wave's highest reach.
- Spray. Droplets burst from the breaking bores, lit by the sun and by your lights.
- Real foam. A lace of bubbles around holes of clear water: thick and bright on breaking crests, thinning into old lace. It is computed, never a tiling texture, and it even shades the seabed below.
- Stays in sync. The bake follows your terrain edits in the Editor.
🏞️ LAKES & RIVERS
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- Lakes. At any height, filling their basin, with waves the size a real lake of that length would raise.
- Rivers. Drawn as a spline: they carve their bed into the terrain, run faster down slopes and slower at the banks, turn white in rapids, carry floating logs, and blend into the lake or sea they flow into.
☀️ LIGHT, ABOVE AND BELOW
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- True colour. Absorption and scattering with depth, and light glowing through the wave crests.
- Reflections. Refraction, screen-space and probe reflections, and sun glints on every ripple.
- Caustics. A simulated ripple net focused by the waves, down to rainbow fringes, with ready-made looks from a lagoon to a swimming pool.
- Your lights. Point and spot lights on and in the water, with shadows and cookies: lanterns glittering on the waves, a flashlight beam cutting through the water.
- Soft sun shadows. They soften with distance, as the sun's disk blurs them.
🤿 UNDER THE SURFACE
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- Underwater light. Fog and colour loss with depth, light shafts shaped by the waves and the foam above, caustics dancing on the seabed.
- Seamless waterline. A waterline across the lens and a smooth crossing through the surface.
🛠️ DROP-IN WORKFLOW
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- One menu. Create an ocean, a lake or a river, bake shorelines, make the selection float.
- A clean Inspector. Every effect in its own section with an on/off switch (what is off costs nothing), the material edited in place, and ready-made Looks for the foam and the caustics.
- Helpful tools. River handles in the Scene view, debug views to tune the look, and help boxes that say what is missing and where to fix it.
- Full source. C# and HLSL, and a documented gameplay API.
📦 INCLUDED
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- A pirate island demo. Shaped like a skull and crossbones: the swell breaking on its coral reef around calm lagoons, a hill lake and its river running down to the sea, a cove with a jetty and rowboats, a ship at anchor, barrels and logs afloat, and schools of reef fish. Fly around, jump between 8 viewpoints, or take the oars.
- Materials. Ocean, Lake, River and Spray.
- 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+ renderer.
- Desktop and consoles. Windows, macOS, Linux and consoles: compute shaders are required. Tested on Windows (DirectX 12).
- Pairs with Drop-In Sky & Weather. Sold separately, not required: the water reflects its live sky and clouds, takes its fog, and ripples under its rain.
🚧 GOOD TO KNOW
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- URP only. No mobile, WebGL or XR in this version.
- One ocean per scene. Lakes are boxes, turned around Y only.
- Visual wakes. Queries and buoyancy don't see the interaction waves.
- No hull masking. Water is not removed inside boats.
- Baked shorelines. They are baked from terrains.
- Screen-space limits. Refraction and screen-space reflections only show what is on screen.
💬 SUPPORT
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Questions or issues? Write to support@havoila.com. Tools > Havoila Studio > Drop-In Water > Contact Support opens an email with your Unity and URP versions filled in.
