Built in Entities

For convenience, appleseed includes a number of built-in entity models, providing a robust foundation with no external dependencies. This document describes these built-in entity models in details.

Table of Contents

• 1. Built-in BSDF Models
• 2. Built-in Camera Models
• 3. Built-in EDF Models
• 4. Built-in Environment Models
• 5. Built-in Environment EDF Models
• 6. Built-in Environment Shader Models
• 7. Built-in Light Models
• 8. Built-in Material Models
• 9. Built-in Object Models
• 10. Built-in Render Layer Assignment Rule Models
• 11. Built-in Surface Shader Models
• 12. Built-in Texture Models

### 10. Built-in Render Layer Assignment Rule Models

10.1. The regex Model

Description

A regex render layer assignment rule allows to assign one or multiple entities whose path matches a given Perl regular expression (cheat sheet, examples) to a given render layer.

The path of an entity is built by concatenating the names of all its parents, starting from the scene (whose name is always scene) and going down until the entity itself is reached. Entity names are separated by / characters. For instance, a sub-assembly "wheel" inside an assembly "truck" will have the following path: scene/truck/wheel.

Parameters

Parameter	Presence	Description
pattern	Required	The regular expression pattern used to select entities.

Example

The following rule, called "rule1", assigns all object instances from the "truck" assembly to a render layer called "truck_layer":

<render_layer_assignment name="rule1" model="regex">
    <parameter name="render_layer" value="truck_layer" />
    <parameter name="entity_type" value="object_instance" />
    <parameter name="order" value="1" />
    <parameter name="pattern" value="scene/truck/.*" />
</render_layer_assignment>