describe how to add keyboard layouts

README.keyboard-layout-handling

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+
+DOSBox-X is not compatible with keyboard layouts it's not prepared for.
+
+The SDL1 library used in this source tree, unlike the official library,
+does not attempt to hack around the issue by forcing Windows to load
+the US keyboard layout for itself.
+
+This document serves as a guide to begin modifying the source code in
+this project to add support for your keyboard layout.
+
+VK_* mapping in SDL1 (Windows):
+- vs2015/sdl/src/video/windib/SDL_dibevents.c: DIB_InitOSKeymapPriv()
+
+DOSBox-X keyboard layout enum:
+- include/keymap.h (DKM_*) constants
+- src/gui/sdlmain.cpp KeyboardLayoutDetect(), DKM_to_string(), DKM_to_descriptive_string()
+- src/gui/sdlmain_linux.cpp (if working on Linux)
+
+You may want to familiarize yourself with the Windows LCID for the locale
+you'd like to add, as well as the VK_* scan codes generated by the keyboard
+for that locale, so that SDL1 mapping can be updated properly.
+
+In Linux, you may want to examine the X11 server keymap table and mod map
+table and look at the X11 codes visible in the mapper to determine how
+to add support.
+