PolySpatial Material support

Several important standard shaders for each pipeline have been mapped to their closest available RealityKit analog. Current support includes:

• Standard URP shaders: Lit, Simple Lit, Unlit, (+TBD - more coming)
• Standard Builtin shaders: Standard, (+TBD – more coming)

Custom shaders

Shaders and materials can be authored for visionOS via the Unity Shader Graph. Behind the scenes, these shader graphs are converted into MaterialX. While MaterialX is very expressive, some Shader Graph nodes have no analog in MaterialX. Within the ShaderGraph editor, unsupported nodes will be indicated by the presence of a # symbol, but please also refer to Shader Graph Support. Both Lit and Unlit root nodes are supported.

ShaderLab, Metal, and other code-based shaders are not available, as RealityKit for visionOS does not currently expose a low level shading language.

Custom UGUI Materials

The default shaders for UGUI components (UI/Default for Image and RawImage; TextMeshPro/Mobile/Distance Field for TextMeshProUGUI; TextMeshPro/Sprite for TMP_SubMeshUI) are mapped to shader graphs that are included with PolySpatial (Shader Graphs/Masking Shader for images and Shader Graphs/Text SDF Smoothstep for text). If you wish to customize UGUI component rendering, you may copy these shader graphs from Packages/PolySpatial/Resources/Shaders into your project's Assets folder, change their names, and modify them to suit your needs. You may then use them in custom materials, for example, by assigning a material using the shader graph to the Material property in an Image or RawImage component, or by assigning the custom shader graph to the Shader property of the material contained within a font asset.

Custom Sprite Materials

Similar to UGUI images, the default sprite shader (Sprites/Default) maps to Shader Graphs/Masking Shader. To customize sprite rendering, you may copy that shader and use it directly in a material referenced by a SpriteRenderer.

Unlit Materials

Universal Render Pipeline/Unlit

For the URP unlit material, PolySpatial supports the Base Map color and texture properties as well as the Opaque and Transparent (with blending mode Alpha) surface types. Alpha Clipping may be enabled; if the Threshold is greater than zero, no blending will be performed (only alpha testing). If Threshold is equal to zero, the material will use alpha-to-coverage mode on visionOS.

Unlit/Color

For the built-in renderer pipeline unlit color material, the Main Color property is supported.

Unlit/Texture

For the built-in renderer pipeline unlit texture material, the Base (RGB) texture is supported.

Unlit/Transparent

For the built-in renderer pipeline unlit transparent material, the Base (RGBA) texture is supported.

Lit Materials

By default, using a lit material will only apply the host system's illumination to your materials. For example, on visionOS, this only applies the system IBL that encodes real world illumination. If you also want to apply Unity's internal illumination to your materials (e.g., light maps, light probes, and/or dynamic lights), you need to opt in to add these more expensive lighting calculations on a per-material basis by wiring up a PolySpatial Lighting Node.

Universal Render Pipeline/Lit

For the URP lit material, the Base Map color and texture are respected, as is the Render Face option and the Surface Inputs Tiling and Offset properties.

When in the Specular workflow and Specular Highlights are enabled, PolySpatial supports the Specular Map texture or the (grayscale) intensity of the associated color. When in the Metallic workflow, PolySpatial supports the Metallic Map texture or intensity and respects the Specular Highlights toggle.

For both workflows, the Smoothness intensity is respected, but smoothness from texture channel (e.g., from Metallic Alpha) is not supported. Normal Map[^1] is supported, but the normal scale is not. Likewise, Occlusion Map is supported, but occlusion intensity is not. Emission color or texture may be specified; if they are both given, the color is reduced to grayscale and acts as a multiplier.

The Opaque and Transparent (with Alpha blend mode) surface types are supported. In Transparent mode, the Preserve Specular flag is respected. Alpha Clipping may be enabled; if the Threshold is greater than zero, no blending will be performed (only alpha testing). If Threshold is equal to zero, the material will use alpha-to-coverage mode on visionOS.

Universal Render Pipeline/Simple Lit

For the URP simple lit material, the options supported are the same as for the lit material, except that there are no Metallic properties and no Occlusion Map.

Universal Render Pipeline/Complex Lit

For the URP complex lit material, the options supported are the same as for the lit material, with the addition of the Clear Coat option and its Mask and Smoothness properties.

Standard

The built-in standard lit material is supported in much the same way as the URP lit material in Metallic workflow. The Albedo texture and color are similarly respected, as is the Metallic map or intensity and the Smoothness intensity (but not the smoothness Source). Normal Map[^1] and Occlusion are supported (but not their corresponding intensities), as is Emission color or texture, Main Maps Tiling and Offset, and the Specular Highlights flag. All rendering modes are supported: Opaque, Transparent, Fade, and Cutout.

Standard (Specular setup)

The built-in lit specular material is supported in the same way as the URP lit material in Specular workflow. The Albedo texture and color are similarly respected, as is the Specular map or (grayscale) intensity and the Smoothness intensity (but not the smoothness Source). Normal Map[^1] and Occlusion are supported (but not their corresponding intensities), as is Emission color or texture, Main Maps Tiling and Offset, and the Specular Highlights flag. All rendering modes are supported: Opaque, Transparent, Fade, and Cutout.

[^1]: Currently, normal maps used in non-shader-graph materials must be imported as the Default texture type--that is, not the Normal map type--with the sRGB (Color Texture) option unchecked.

Special Purpose Materials

TextMeshPro/Distance Field

TextMeshPro/Mobile/Distance Field

The TMP distance field materials are converted to shader graph materials that respect the Face Color and Face Texture properties only.

UI/Default

The UI default material is converted to an unlit material that respects the tint and texture properties.

Universal Render Pipeline/Particles/Unlit

The URP unlit particles material is converted to an unlit material that respects the Base Map texture and color, the Surface Type and the Blending Mode (except the Multiply Blending Mode).

Universal Render Pipeline/Particles/Lit

The URP lit particles material is converted to a lit material that respects the Base Map texture and color, the Metallic Map and intensity, the Normal Map, the Smoothness intensity, the Normal intensity, Emission Map texture and color, the Surface Type and the Blending Mode (except the Multiply Blending Mode).

Particles/Standard Surface

The Built-in Render Pipeline lit particles material is converted to a lit material that respects the Albedo texture and color, the Metallic Map and intensity, the Normal Map, the Smoothness intensity, the Normal intensity, Emission Map texture and color, and the Surface Type.

AR/Basic Occlusion

AR/Occlusion

The occlusion materials are converted to basic equivalents.

Shader Graph materials

Shader Graphs may use the Builtin or URP targets and the Unlit or Lit materials. All output blocks are supported. For more information about shader graph support, see the shader graph conversion notes.

Fallback Materials

If an unsupported shader is used PolySpatial will attempt to fallback to a basic Lit or Unlit shader. This behaviour can be toggled with the "Enable Fallback Shader Conversion" in the PolySpatial settings. If this is disabled unsupported shaders will be rendered as magenta on device.