Allow using shader processing tools for custom shaders

* This is primarily useful for HLSL on Vulkan, but could be used with any other
  combination. If multiple tools can perform the conversion, the highest
  priority one is used.

docs/how/how_custom_visualisation.rst

@@ -6,7 +6,9 @@ This page details how to set up a custom shader for visualisation. This can be u
 Introduction
 ------------
 
-The basic process of setting up the custom shader involves writing a ``.hlsl`` or ``.glsl`` file that will be compiled and used by RenderDoc. Note that the type used matches the API used, and RenderDoc will automatically list only the hlsl shaders you have if you load a log with D3D11 or D3D12, and glsl for OpenGL or Vulkan.
+The basic process of setting up the custom shader involves writing a shader file that will be compiled and used by RenderDoc. Note that you can use any language that is either natively accepted by the graphics API used, or any language that can be compiled to an accepted shader.
+
+For example on D3D11 or D3D12, hlsl is the only language usable by default, but on Vulkan you can use hlsl or glsl as long as a compiler is available.
 
 There are several special global variables that can be specified and will be filled in with values by RenderDoc.
 

docs/how/how_edit_shader.rst

@@ -11,7 +11,7 @@ How to edit a custom shader
 
 :doc:`Custom visualisation shaders <how_custom_visualisation>` allow you to define your own transformation on any texture you're viewing before it is displayed. Mostly this is useful for decoding packed or custom-format data, or displaying some data in a more visually intuitive fashion.
 
-These shaders live as ``.hlsl`` or ``.glsl`` files in the application storage directory ( ``%APPDATA%/qrenderdoc/`` on windows or ``~/.local/share/qrenderdoc`` elsewhere), and can be edited in your editor of choice, any changes saved will be reloaded. Note however that there is currently no way to see the compile warnings or errors produced when editing externally.
+These shaders live as files in the application storage directory ( ``%APPDATA%/qrenderdoc/`` on windows or ``~/.local/share/qrenderdoc`` elsewhere), and can be edited in your editor of choice, any changes saved will be reloaded. Note however that there is currently no way to see the compile warnings or errors produced when editing externally.
 
 To edit a shader inside RenderDoc simply click the edit button |page_white_edit| when you have selected your custom shader for use. This will launch a new window with the custom shader and any changes you make to this shader will be saved to the file and compiled and reflected in the texture viewer as long as you have that custom shader selected.