Shader Apply Flags

The apply statement allows specification of possible uses for the shader. The shader_type_list consists of a comma-separated list of one or more of the following keywords:

keyword	shader application
`lens`	lens shader in a camera
`material`	material shader in a material
`light`	light shader
`shadow`	shadow shader in a material
`environment`	environment shader in a material or camera
`volume`	volume shader in a material or camera
`texture`	texture shader
`photon`	photon shader in a material
`geometry`	geometry shader
`displace`	displacement shader in a material
`lightmap`	lightmap shader in a material
`emitter`	photon emitter shader in a light
`output`	output shader in a camera
`state`	state shader in options

If the apply statement is missing, the application purpose of a shader is unknown. This may be the case for general base shaders, for example, which can be used in any context (like a noise shader). Apply lists help user interfaces to categorize shaders. mental ray performs no checks to make sure that shaders are used only in legal contexts, and in fact ignores the apply list completely.