Mist

Mist is a volumetric fog package for Unity's Universal Render Pipeline, implemented from HDRP's fog system and optimized for URP's architecture. It provides height fog and atmospheric scattering with configurable attenuation, height, start distance, and range, where fog color can be a constant HDR color, the skybox, or a custom cubemap. The package features froxel-based volumetric fog with contribution from directional, point, and spot lights, including shadows, anisotropic scattering, emission, and global illumination from adaptive or ambient probe volumes. Per-light volumetric overrides allow independent control of intensity, shadow strength, fade distance, source radius, and temporal evaluation, with rapidly changing lights evaluated per frame. Local fog volumes use oriented boxes or ellipsoids with interior and radial fades, camera-distance fading, priority, and multiple blending modes, supported by 3D texture masks with independent tiling and scrolling. A Fog Volume Shader Graph target enables procedural or texture-driven density and scattering color, while transparent Shader Graph integration supports URP Lit and Unlit materials via a manual node and HLSL helper. Screen-space multiple scattering approximates secondary scattering behind dense fog, and configurable denoising offers temporal reprojection, Gaussian filtering, both, or none, with history rejection and automatic invalidation after camera cuts or configuration changes. Quality and performance are adjustable through Mobile, VR, Balanced, Quality, and Cinematic presets, or Manual mode for direct control over volumetric buffer resolution and depth-slice count, with independent adjustments for volumetric distance, light evaluation, denoising, and local-volume resolution. The package includes a Rendering Debugger panel with views for raw integration, filtered lighting, final fog, extinction, light contribution, froxel layout, and effective light radius, plus scene-view gizmos displaying volume bounds, blend regions, mask flow, and volumetric light radii. Runtime diagnostics expose active buffer dimensions, memory estimates, light and volume counts, and quality settings. Included samples demonstrate ground smoke, procedural fumes, local cloud-like fog, animated texture-masked fog, point-lit fog volumes, blending modes, procedural volume shapes, and screen-space multiple scattering.