Устанавливает ключевое слово шейдера, которое активируется данным материалом.
Shaders can be internally compiled into multiple variants, and then the matching one is picked based on material keywords (EnableKeyword and DisableKeyword), or globally set shader keywords (Shader.EnableKeyword and Shader.DisableKeyword).
See Also: DisableKeyword, shaderKeywords, Accessing Materials via Script, multiple shader program variants.