I was thinking of writing a custom GLSL shader to produce a unique texture blending effect. After doing some digging, I came across these pages which seem to suggest that there’s something that you can tweak the Material properties while using Game Engine renderer that lets you load your vertex and fragment shaders directly into it (instead of having to load at runtime using Python):
Trouble is, I can’t find this ‘custom shaders’ panel. These changes were in the Harmony 1 branch which supposedly was merged into Blender after 2.63. Has this feature since been depreciated? Or am I just not looking in the right place?