Possible to get Skybox Cubemap ref from within shader?

Is it possible to get the current skybox material's cubemap from within a shader?
Kind of like how you can use "unity_FogDensity" to get the global fog density setting.

So instead of having a public cubemap variable that I drag a cubemap into for my material, it would just pull the skybox's cubemap one into the shader.


EDIT: This might make it easier. Even if I can access " RenderSettings.customReflection" via a shader I can do what I want. I've been digging through cginc files to find any references to properties but haven't had any luck yet.

 

Ok so not the cleanest solution, but currently I have a script that sets my global shader property to the custom reflection probe in the render settings:

Code (CSharp):

1. Shader.SetGlobalTexture("_Sky", RenderSettings.customReflection);

This code is on an empty gameobject, set to run on awake and to run in the editor.

 

From the unity vertex and fragment examples:

Code (CSharp):

1. // sample the default reflection cubemap, using the reflection vector
2. half4 skyData = UNITY_SAMPLE_TEXCUBE(unity_SpecCube0, i.worldRefl);
3. // decode cubemap data into actual color
4. half3 skyColor = DecodeHDR (skyData, unity_SpecCube0_HDR);