* Add scaling for vfnts and scale multipler to gr_string
* nullptr
* Add scaling to a couple other string operations
* Add scaling features to additional bitmap drawing methods
* Implement framework for rendering hud gauges in config mode
* fix merge error
* address feedback
This will ensure that Lua functions will always be executed in the
correct Lua state. Since we now have multiple threads (which are
different lua_State objects) it is possible that the current code could
execute a Lua function in the main state instead of the thread that is
currently executing. This can lead to weird behavior and probably also
to issues inside Lua.
The new gauge can be accessed by the scripting API with which a function
can be set which will be called when this gauge is rendered. This can be
used for exposing the HUD gauge positioning and RTT options to the
scripting API without a lot of work needed for the script writer.
There is currently only one rendering function implemented since this is
only a proof of concept.