====== Shader Keywords ======

Recommended reading:
  * https://docs.unity3d.com/Manual/SL-MultipleProgramVariants.html

===== Shader Variant Fallbacks =====

Keywords will only take effect if a shader variant is present in the build with that exact set of keywords enabled.

If you set the keywords:
<code c#>
cmd.EnableShaderKeyword("_KEYWORD1");
cmd.EnableShaderKeyword("_KEYWORD2");
cmd.EnableShaderKeyword("_KEYWORD3");
</code>

But the only shaders present in the build (after stripping) are:
<code>
_KEYWORD1 _KEYWORD2
_KEYWORD2 _KEYWORD3
</code>

Unity will apply a fallback mechanism((I'm not sure what the fallback mechanism is, exactly)) to select a variant shader with the closest set of keywords.

===== Debugging Shader Variants =====

Sometimes it's useful to debug which shader variants and keywords are actually being included into a build. The "Compiled Code" drop-down in the shader inspector has a button to show the variants included in a build, and more importantly, //why//. Some keywords are always included in a build, globally, and some are only included if a scene uses a material with those keywords.

{{ :unity_4llyy1titq.png?200 }}