> ## Documentation Index > Fetch the complete documentation index at: https://mintlify.com/AcChosen/VR-Stage-Lighting/llms.txt > Use this file to discover all available pages before exploring further. # Volumetric Rendering > Volumetric light cone rendering techniques and properties ## Overview Volumetric shaders create visible light beams and cones by rendering transparent meshes with sophisticated noise and gradient effects. These shaders are the most computationally intensive part of the VR Stage Lighting system and include multiple quality modes for performance optimization. ## Shader Paths ### DMX Control * `VRSL/Standard Mover/Volumetric` * `VRSL/Wash Mover/Volumetric` ### AudioLink Control * `VRSL/AudioLink/Standard Mover/Volumetric` * `VRSL/AudioLink/Wash Mover/Volumetric` ## Core Volumetric Properties ### Quality Modes Enable high quality volumetric mode (experimental). Uses `_NoiseTexHigh` instead of `_NoiseTex` for better visual quality. Performance mode that disables noise sampling and extra texture reads. Significant performance boost at the cost of visual quality. Requires depth light to function. When disabled, volumetric will render without depth fade. ### Textures Main light texture for the volumetric cone. Typically a radial gradient. Standard quality noise texture for volumetric distortion. High quality noise texture used when `_HQMode` is enabled. ### Noise Configuration Enable high quality magic noise effect. Enable medium quality magic noise effect. Enable 2D noise texture sampling. Base noise strength/intensity. Random seed value for noise variation. ### Magic Noise Settings Magic noise creates dynamic, animated 3D noise patterns. Three quality presets are available: #### High Quality Mode Outside magic noise scale (high quality). Inside magic noise scale (high quality). Magic noise X axis scroll speed (high quality). Magic noise Y axis scroll speed (high quality). Magic noise Z axis scroll speed (high quality). Magic noise strength (high quality). #### Default Mode Outside magic noise scale (default quality). Inside magic noise scale (default quality). Magic noise X scroll (default quality). Magic noise Y scroll (default quality). Magic noise Z scroll (default quality). Magic noise strength (default quality). #### Potato Mode Outside magic noise scale (potato quality - typically unused). Inside magic noise scale (potato quality - typically unused). Magic noise X scroll (potato quality). Magic noise Y scroll (potato quality). Magic noise Z scroll (potato quality). Magic noise strength (potato quality). ### Intensity and Fade Maximum cone intensity. Higher values create brighter, more visible volumetric beams. Edge fade strength. Controls how sharply the cone edges fade out. Inner fade strength. Creates a hollow cone effect when increased. Curve for inner intensity falloff. Distance-based fade. Cone fades at distance. Depth blending amount. Controls soft particle intersection with geometry. ### Blinding Effect Strength of the blinding/bloom effect when looking into the light. Angle modifier for blinding effect. Adjusts viewing angle sensitivity. ### Gradient Controls Gradient modifier for solid beams (no GOBO). Gradient modifier when GOBO is active. ### GOBO Beam Splitting Creates stripe effects in the volumetric cone for different GOBO patterns: Enable beam splitting for GOBOs 2-8. Stripe split frequency for GOBO 2. Stripe split intensity for GOBO 2. Stripe split frequency for GOBO 3. Stripe split intensity for GOBO 3. Stripe split frequency for GOBO 4. Stripe split intensity for GOBO 4. Stripe split frequency for GOBO 5. Stripe split intensity for GOBO 5. Stripe split frequency for GOBO 6. Stripe split intensity for GOBO 6. Stripe split frequency for GOBO 7. Stripe split intensity for GOBO 7. Stripe split frequency for GOBO 8. Stripe split intensity for GOBO 8. ### Animation Speed of intensity pulse animation. ## Rendering Properties Volumetric rendering mode: * `0`: HQTransparent - Best quality, most expensive * `1`: Transparent - Standard transparency * `2`: AlphaToCoverage - MSAA-based transparency Destination blend mode. Typically set to One for additive blending. Blend operation. Depth buffer writing. Always false for volumetrics. Enable alpha to coverage mode. ## Performance Optimization ### Quality Levels **High Quality** - Best visuals, lowest performance: ``` _HQMode = true _PotatoMode = false _MAGIC_NOISE_ON_HIGH = true _MAGIC_NOISE_ON_MED = true _2D_NOISE_ON = true ``` **Standard Quality** - Balanced: ``` _HQMode = false _PotatoMode = false _MAGIC_NOISE_ON_HIGH = false _MAGIC_NOISE_ON_MED = true _2D_NOISE_ON = true ``` **Performance Mode** - Best performance: ``` _HQMode = false _PotatoMode = true _MAGIC_NOISE_ON_HIGH = false _MAGIC_NOISE_ON_MED = false _2D_NOISE_ON = false ``` ### Shader Variants The volumetric shader compiles multiple variants: * `_MAGIC_NOISE_ON_HIGH` - High quality noise * `_MAGIC_NOISE_ON_MED` - Medium quality noise * `_USE_DEPTH_LIGHT` - Depth-based effects * `_POTATO_MODE_ON` - Performance mode * `_HQ_MODE` - High quality mode * `_2D_NOISE_ON` - 2D noise sampling * `_ALPHATEST_ON` - Alpha testing Total possible combinations: 128 variants ### Optimization Tips 1. **Reduce Cone Length**: Shorter cones have less overdraw * Use `_ConeLength` and `_MaxConeLength` conservatively 2. **Simplify Noise**: Disable unused noise features * Turn off `_MAGIC_NOISE_ON_HIGH` if not needed * Use `_PotatoMode` on low-end hardware 3. **Limit Fixture Count**: Volumetrics are expensive * Consider using fewer fixtures with higher intensity * Disable volumetrics for background/ambient lights 4. **Adjust Fade Settings**: Reduce visibility distance * Lower `_DistFade` for shorter render distance * Increase `_FadeStrength` for sharper edges (less translucency layers) 5. **Use Lower Resolution**: If using render textures * Render volumetrics to lower resolution RT * Upscale for final composite ## Technical Details ### Vertex Shader Calculations The vertex shader pre-calculates: * Blinding effect based on view angle * Camera angle and fade * Stripe/split information * Cone width * World direction for depth correction * Intensity, strobe, GOBO selection, and spin speed * RGB color values ### Fragment Shader Operations The fragment shader performs: * Multi-layer noise sampling (2D + 3D magic noise) * Depth texture reading for soft particles * UV-based gradient calculations * GOBO stripe splitting * Edge fade calculations * Color blending and saturation * Mirror depth correction ### Performance Characteristics **Vertex Shader**: Lightweight * Simple position transforms * Minimal branching * Instanced property access **Fragment Shader**: Heavy * Up to 3 texture samples per pixel (in HQ mode): * `_LightMainTex` * `_NoiseTex` or `_NoiseTexHigh` * `_CameraDepthTexture` * Complex noise calculations * Distance-based fade calculations * High overdraw on large cones ### Depth Fade Implementation Soft particle intersection uses depth comparison: ```hlsl theme={null} float sceneZ = LinearEyeDepth(SAMPLE_DEPTH_TEXTURE_PROJ( _CameraDepthTexture, UNITY_PROJ_COORD(i.screenPos))); float partZ = i.screenPos.z; float fade = saturate((sceneZ - partZ) / _FadeAmt); ``` This creates smooth transitions where volumetric cones intersect geometry. ## AudioLink Specific Multiplier for render texture intensity when using AudioLink. Use traditional texture sampling instead of AudioLink-specific sampling. Intersection modification for AudioLink mode. ## See Also * [Moving Light Shaders](/api/shaders/moving-lights) - Parent shader properties * [Shader Overview](/api/shaders/overview) - System architecture * [Static Lights](/api/shaders/static-lights) - Static light alternatives