Add mentions of glkitty to the docs

Fixes #3111

docs/graphics-protocol.rst

@@ -38,6 +38,7 @@ Some programs that use the kitty graphics protocol:
  * `neofetch <https://github.com/dylanaraps/neofetch>`_ - A command line system
    information tool
  * `viu <https://github.com/atanunq/viu>`_ - a terminal image viewer
+ * `glkitty <https://github.com/michaeljclark/glkitty>`_ - C library to draw OpenGL shaders in the terminal with a glgears demo
 
 
 .. contents::

docs/integrations.rst

@@ -123,3 +123,6 @@ Miscellaneous
 `weechat-hints <https://github.com/GermainZ/kitty-weechat-hints>`_
     URL hints kitten for WeeChat that works without having to use WeeChat's
     raw-mode.
+
+`glkitty <https://github.com/michaeljclark/glkitty>`_
+    C library to draw OpenGL shaders in the terminal with a glgears demo