Set PBR Alpha Adv

Node Introduction

This node is used to set the transparency and Alpha mode of PBR materials. Through this node, we can adjust the transparency value and select the corresponding Alpha mode for the material.

Inputs

• MenuItem - Menu item.

Outputs

• None

Node Properties

• PrimTag -

  The unique identifier for this object is PrimTag. When a model is composed of multiple linked prims, each prim's description must include a PrimTag formatted as ez:xxxxx; (starting with ez: and ending with ;), enabling scripts to accurately locate target prims for operations. This field may be left empty for single-prim models.

• Face - specified face. Select a face from the dropdown list.

• Alpha - Transparency. This parameter is used to set the transparency of the material. The transparency range is 0-1, where 0 indicates fully transparent and 1 indicates fully opaque.

• AlphaMode - Alpha Mode: This parameter is used to set the Alpha mode of the material. The following options are available:

  • PRIM_GLTF_ALPHA_MODE_OPAQUE - Opaque.
  • PRIM_GLTF_ALPHA_MODE_MASK - Mask.
  • PRIM_GLTF_ALPHA_MODE_BLEND - Blend.

Side Note

These three Alpha mode options have different use cases, such as:

• PRIM_GLTF_ALPHA_MODE_OPAQUE - Opaque, ignores the transparency value and renders the material as fully opaque. Suitable for opaque materials. Use this when you need fully opaque materials, such as metal, wood, or other solid surfaces.
• PRIM_GLTF_ALPHA_MODE_MASK - Mask, renders the material as fully opaque when the alpha value is greater than the specified alpha cutoff value; otherwise, renders it as fully transparent. This mode is typically used for materials with distinct transparent areas (e.g., holes or irregular transparent regions in textures). By setting the alpha cutoff value, you can decide which areas are fully opaque and which are fully transparent. It is often used for simple transparency effects, such as leaf shapes or wire mesh.
• PRIM_GLTF_ALPHA_MODE_BLEND - Blend, determines the transparency of the material based on the alpha value. The rendering blends in linear color space. Similar to Blinn-Phong mode, this mode may encounter depth sorting and performance issues. If possible, it is recommended to use PRIM_GLTF_ALPHA_MODE_MASK mode.

To learn more, refer to here

Corresponding Relationship