GPU Rain VFX — Roof & Indoor Occlusion · URP & HDRP

Tired of rain pouring straight through your roofs, ceilings, tunnels and building interiors? The inability to tell indoor from outdoor is a Unity headache that's existed for almost a decade — and this system finally solves it. Rain VFX — Roof & Indoor Occlusion is a complete, GPU-driven rain solution built entirely on Visual Effect Graph for both URP & HDRP. A full rain simulation — raindrops, splashes, ripples and mist — that accurately respects your architecture and stops at roofs, no more rain leaking into rooms, buildings or under meshes, without a single CPU collider or physics raycast. ━━━━━━━━━━━━━━━━━━━ 🎭 ROOF & INDOOR OCCLUSION 🌧️ REAL-TIME ROOF & INDOOR OCCLUSION · An orthographic camera renders a GPU depth/height map of your covers every frame. The VFX Graph reads it in real time and stops any raindrop, splash, or mist particle the instant it falls below a roof — no CPU colliders, no raycasts. 🎯 THREE MASKING MODES FOR ANY PROJECT · Baked (zero runtime cost, static levels), Realtime Fixed Area (dynamic covers like moving cars or rotating roofs), and Realtime Around Player (the mask follows your target, optimized for open worlds). 🏠 ONE-CLICK OCCLUDER PROXY WORKFLOW · Turn any mesh — a cube, a building, a rigged and animated NPC — into a rain shelter with a single right-click. Batch-create proxies for multiple objects at once as a single Undo step, or build them directly inside Prefab Mode so every instance of a modular house or vehicle inherits the proxy automatically. 🦴 ANIMATED CHARACTERS FULLY SUPPORTED · Proxies track bones, root motion, and rig movement in real time — a walking NPC with an umbrella deforms correctly and blocks the rain dynamically, with automatic hierarchy validation when the proxy is created. ⚙️ MINIMAL-OVERHEAD PROXY RENDERING · Proxy objects are automatically stripped of scripts, colliders, and physics, and optimized for a mask-only render pass — no shadows, no light probes, no wasted GPU cost, no material setup required, ever. Even animated proxies add only a negligible per-frame cost. ━━━━━━━━━━━━━━━━━━━ 🌧️ FULL GPU RAIN ENGINE 🌊 FULL GPU RAIN SIMULATION · Raindrop impacts trigger splashes, expanding water ripples, and localized impact mist in a single connected VFX Graph system — with an optional heavy rolling global mist layer for dense storms. 🌐 AREA-BASED DENSITY SPAWNING · Automatically recalculates raindrop density per square meter as you resize the spawn area, so your rain stays consistent whether you're covering a small courtyard or an entire open world. 📐 SURFACE-AWARE RIPPLE SPAWNING · Ripples check the collision surface angle and only appear on flat, horizontal ground — automatically ignoring vertical walls, so splashes never look glued to a cliff face. 🏔️ SLOPE-REACTIVE SPLASH PHYSICS · Splash particles bounce based on the surface's collision normal, with separate upward and radial force multipliers — rain hitting a rooftop or a slope kicks up water at a physically correct angle. 🧊 DEPTH BUFFER COLLISIONS · Raindrops collide with your scene geometry using the camera's depth buffer to detect surface hits, trigger splash/ripple/mist events, and cut particle lifetime on impact. 🎬 NEAR CAMERA ENHANCEMENT (NCE) · A dedicated sphere around your camera adds cinematic, blurred drops in front of the lens, or a clean "protective dome" that keeps particles off the camera entirely. ━━━━━━━━━━━━━━━━━━━ 🧩 PRODUCTION-READY SETUP 🧠 70+ EXPOSED PARAMETERS · Full Inspector control over the entire rain and occlusion system — particle lifetime, velocity-based stretching, color gradients, spawn rates, masking modes and occlusion offsets — available in both physically Lit and Unlit variants, no VFX Graph editing required for day-to-day tuning. 🧩 SETUP ASSISTANT · A built-in mentor tool scans your Project-Wide and Scene settings (render pipeline, textures, layers, camera culling mask) and flags every missing piece before you press Play — dramatically cutting down on trial-and-error set