Skybox Setup

VROcean includes two custom skybox shaders designed to complement the ocean rendering. This guide covers configuration of both the day and night skybox options.

Included Skybox Shaders

Shader	Description
Custom/S_CloudySky_Day	Daytime sky with procedural 3D clouds, sun glow, and stars
Custom/S_StarNightSky_Night	Night sky with stars, moon, and 2D cloud layer

Both shaders support VR single-pass stereo instanced rendering.

Creating a Skybox Material

1. In the Project window, right-click and select Create > Material
2. Name it appropriately (e.g., M_DaySky or M_NightSky)
3. In the Inspector, change the Shader dropdown to Custom/S_CloudySky_Day or Custom/S_StarNightSky_Night
4. Configure the properties as desired
5. Assign the material to your biome profile's Skybox Material field

Day Sky Configuration

The S_CloudySky_Day shader provides a full daytime sky with procedural elements.

Day sky material with key properties highlighted

Sky Colors

Controls the gradient from horizon to zenith.

Parameter	Description
Horizon Color	Color at the horizon line
Mid Horizon Color	Transitional color above horizon
Base Color	Primary sky color
High Color	Color at the zenith (straight up)
Ground Color	Color below the horizon

The shader blends between these colors based on vertical angle.

Sky Gradient

Parameter	Range	Description
Horizon Height	-1 to 1	Vertical offset of the horizon line
Gradient Offset	-1 to 1	Shifts the color gradient up or down
Gradient Scale	0.1 - 5	Compresses or expands the gradient
Vertical Scale	0.1 - 3	Stretches the sky dome vertically

Stars

Stars are sampled from a cubemap texture for seamless coverage.

Parameter	Description
Star Noise Cubemap	Cubemap texture containing star pattern
Star Density	Tiling multiplier for star pattern
Star Opacity	Overall star visibility (0 = invisible)
Star Threshold	Cutoff for which noise values become stars

Stars are masked by vertical position, fading out near the horizon.

Sun

The sun is rendered procedurally based on the scene's directional light.

Parameter	Range	Description
Sun Enabled	Toggle	Show or hide the sun disc
Sun Horizon Angle	-180 to 180	Horizontal position in degrees
Sun Size	0.01 - 0.2	Angular size of the sun disc
Sun Color	Color	Tint of the sun
Sun Intensity	0 - 3	Brightness multiplier
Sun Glow Size	0.01 - 0.5	Size of the glow halo
Sun Glow Intensity	0 - 2	Brightness of the glow
Sun Height	-0.1 to 0.2	Vertical position offset

Moon

Optional moon rendering with texture support.

Parameter	Description
Moon Enabled	Toggle moon visibility
Moon Texture	2D texture for moon surface
Moon Direction	Normalized direction vector
Moon Size	Angular size
Moon Color	Tint color
Moon Intensity	Brightness multiplier

Clouds

Clouds are generated from a 3D noise texture for volumetric appearance.

Parameter	Description
Cloud Noise Texture	3D texture for cloud generation
Cloud Tiling	UV scale for cloud pattern
Wind Speed	Animation speed of cloud movement
Cloud Light Color	Color of cloud highlights
Cloud Mid Color	Color of cloud midtones
Cloud Dark Color	Color of cloud shadows
Cloud Opacity	Overall cloud visibility
Cloud Height	Vertical position of cloud layer
Cloud Edge	Softness of cloud boundaries
Cloud Contrast	Sharpness of cloud definition

Fog

Parameter	Range	Description
Fog Height	0.1 - 10	Vertical falloff of fog
Fog Opacity	0 - 1	Maximum fog density at horizon

The fog color is taken from Unity's RenderSettings.fogColor.

Night Sky Configuration

The S_StarNightSky_Night shader provides a nighttime atmosphere with stars and clouds.

Night sky material properties

Sky Colors

Parameter	Description
Sky Zenith Color	Color at the top of the sky
Sky Horizon Color	Color at the horizon
Ground Color	Color below the horizon
Sky Blend Offset	Shifts the horizon blend point
Sky Blend Power	Controls blend curve sharpness

Sun

The night shader includes an optional sun for twilight scenes.

Parameter	Description
Sun Enabled	Toggle sun visibility
Sun Direction	Direction vector for sun position
Sun Color	Sun tint
Sun Size	Angular size of disc
Sun Glow Size	Size of surrounding glow
Sun Glow Intensity	Glow brightness

Clouds

Night clouds use a 2D texture projected onto the sky dome.

Parameter	Description
Cloud Texture	2D cloud texture (use alpha for opacity)
Cloud Scale	UV tiling scale
Cloud Offset	UV offset
Cloud Speed	Animation speed
Cloud Direction	Movement direction (0 - 1, maps to 360 degrees)
Cloud Opacity Scale	Multiplier for texture alpha
Cloud Opacity Offset	Additive offset for opacity
Cloud Sun Color	Color when lit by sun/moon
Cloud Back Color	Color on shadowed side
Cloud Ambient	Ambient light contribution
Cloud Blend Offset	Lighting blend adjustment
Cloud Blend Power	Lighting blend curve
Front Scatter Power	Forward scattering intensity
Back Scatter Power	Back scattering intensity
Scatter Blend	Balance between scatter modes

Cloud Horizon Fade

Parameter	Description
Cloud Horizon Fade	Rate at which clouds fade near horizon
Cloud Zenith Fade	Rate at which clouds fade near zenith

Fog

Parameter	Description
Fog Power	Falloff curve for horizon fog
Fog Offset	Vertical offset for fog start

Matching Skybox to Ocean

For visual coherence, coordinate your skybox and ocean settings:

Color Harmony

Time of Day	Sky Horizon	Ocean Shallow	Ocean Albedo
Sunrise	Warm orange	Warm teal	Desaturated blue
Midday	Light blue	Bright cyan	Saturated blue
Sunset	Pink/purple	Warm aqua	Deep blue-purple
Night	Dark blue	Dark teal	Very dark blue

Sun Position

The biome profile's Solar Config > Rotation should match the skybox sun position:

// Example: Sun at 30 degrees elevation, 45 degrees from north
solarConfig.Rotation = new Vector3(30f, 45f, 0f);

// For the day skybox, set matching values
// Sun Horizon Angle: 45
// Sun Height: ~0.05 (corresponds to 30 degree elevation)

Fog Consistency

Ensure the fog color in Atmosphere Config complements the skybox horizon color:

// Fog should blend smoothly into the skybox horizon
atmosphereConfig.FogColor = skyboxHorizonColor;

Generating Cloud Textures

3D Noise Texture (Day Sky)

The day sky shader requires a 3D texture for volumetric clouds. You can generate one using the included tool:

1. Open Window > VROcean > Skybox Noise Generator
2. Configure resolution (64x64x64 is sufficient for most cases)
3. Adjust noise parameters
4. Click Generate and save the asset

2D Cloud Texture (Night Sky)

The night sky shader uses a standard 2D texture with alpha channel:

• RGB channels: Cloud color (usually white or light gray)
• Alpha channel: Cloud density

Tileable panoramic cloud textures work best.

Skybox Presets

Clear Day

Horizon Color: (0.75, 0.85, 1.0)
Base Color: (0.4, 0.6, 0.9)
High Color: (0.2, 0.35, 0.8)
Cloud Opacity: 0.3
Sun Intensity: 1.5
Fog Opacity: 0.2

Overcast Day

Horizon Color: (0.6, 0.62, 0.65)
Base Color: (0.5, 0.52, 0.55)
High Color: (0.45, 0.47, 0.5)
Cloud Opacity: 0.9
Cloud Contrast: 0.3
Sun Intensity: 0.5
Fog Opacity: 0.4

Sunset

Horizon Color: (1.0, 0.5, 0.2)
Mid Horizon Color: (0.9, 0.4, 0.3)
Base Color: (0.5, 0.3, 0.5)
High Color: (0.2, 0.15, 0.4)
Sun Horizon Angle: 270
Sun Height: -0.02
Sun Color: (1.0, 0.6, 0.2)
Sun Glow Intensity: 1.5
Cloud Sun Color: (1.0, 0.7, 0.4)

Clear Night

Sky Zenith Color: (0.02, 0.03, 0.08)
Sky Horizon Color: (0.05, 0.08, 0.15)
Star Opacity: 0.8
Star Threshold: 0.97
Moon Enabled: true
Moon Intensity: 1.0
Cloud Opacity Scale: 0.2

Stormy

Horizon Color: (0.25, 0.27, 0.3)
Base Color: (0.2, 0.22, 0.25)
High Color: (0.15, 0.16, 0.18)
Cloud Opacity: 1.0
Cloud Contrast: 0.7
Cloud Dark Color: (0.1, 0.1, 0.12)
Sun Enabled: false
Fog Opacity: 0.6
Fog Height: 3.0

Performance Considerations

Both skybox shaders are lightweight and suitable for VR:

Feature	Performance Impact
Star rendering	Minimal (single texture sample)
Procedural sun	Minimal (math only)
3D cloud sampling	Low-moderate (two texture samples)
2D cloud sampling	Minimal (single texture sample)

For maximum performance on Quest standalone:

• Reduce cloud texture resolution
• Lower Cloud Opacity to skip cloud calculations on more pixels
• Disable moon texture sampling if not needed

Troubleshooting

Skybox Not Visible

• Verify the material is assigned in the biome profile
• Check that RenderSettings.skybox is being set (SceneSystem handles this)
• Ensure the camera's Clear Flags is set to "Skybox"

Clouds Look Flat

• For day sky: Ensure a 3D texture is assigned, not a 2D texture
• Increase Cloud Contrast for more definition
• Adjust Cloud Tiling for better scale

Sun Position Wrong

• The skybox sun is separate from the directional light
• Manually align Sun Horizon Angle and Sun Height to match your directional light rotation
• Or disable the skybox sun and rely on the directional light for sun representation

Stars Visible During Day

• Reduce Star Opacity to 0 for daytime profiles
• Stars are always calculated but can be made invisible

Seam Visible at Horizon

• Adjust Horizon Height to hide the seam
• Increase Fog Opacity to blend the transition
• Ensure Ground Color matches the horizon

Next Steps

• Biome Profiles - Assign skybox to profiles
• Visual Tuning - Match ocean colors to skybox
• Wave Settings - Configure wave behavior