Custom Actor Shader
When rendering most characters and background actors (generic excluded), a special shader is used to handle semi-transparency overdraw and support various transition effects.
You can override the default shader by assigning a material to the Custom Texture Material property available in the actor configuration menu.
Be aware that the shader used by the assigned material is expected to have specific properties; check the default shader at Naninovel/Resources/Naninovel/Shaders/TransitionalTexture for reference.
When an actor is represented as a sprite in the scene, the Custom Sprite Material property is available (this is the case for non-generic implementations when they're not rendered to texture). By default, a simple unlit transparent shader is used; if you want to implement lighting or surface effects, assign a material with a custom shader to the property.
EXAMPLE
Check the actor shader sample for an example of how to create and use a texture shader for adding custom transition effects and a sprite shader with lighting and self-illumination support to simulate time of day for a background actor.