SDL: Use scancodes for keybindings

irr/include/IrrlichtDevice.h

@@ -16,6 +16,7 @@
 #include "IrrCompileConfig.h"
 #include "position2d.h"
 #include "SColor.h" // video::ECOLOR_FORMAT
+#include <variant>
 
 namespace irr
 {
@@ -345,6 +346,27 @@ class IrrlichtDevice : public virtual IReferenceCounted
 	{
 		return video::isDriverSupported(driver);
 	}
+
+	//! Get the scancode of the corresponding keycode.
+	/**
+	\param key The keycode to convert.
+	\return The implementation-dependent scancode for the key (represented by the u32 component) or, if a scancode is not
+	available, the corresponding Irrlicht keycode (represented by the EKEY_CODE component).
+	*/
+	virtual std::variant<u32, EKEY_CODE> getScancodeFromKey(const Keycode &key) const {
+		if (auto pv = std::get_if<EKEY_CODE>(&key))
+			return *pv;
+		return (u32)std::get<wchar_t>(key);
+	}
+
+	//! Get the keycode of the corresponding scancode.
+	/**
+	\param scancode The implementation-dependent scancode for the key.
+	\return The corresponding keycode.
+	*/
+	virtual Keycode getKeyFromScancode(const u32 scancode) const {
+		return Keycode(KEY_UNKNOWN, (wchar_t)scancode);
+	}
 };
 
 } // end namespace irr

irr/include/Keycodes.h

@@ -3,6 +3,7 @@
 // For conditions of distribution and use, see copyright notice in irrlicht.h
 
 #pragma once
+#include <variant>
 
 namespace irr
 {
@@ -182,4 +183,30 @@ enum EKEY_CODE
 	KEY_KEY_CODES_COUNT = 0x100 // this is not a key, but the amount of keycodes there are.
 };
 
+// A Keycode is either a character produced by the key or one of Irrlicht's codes (EKEY_CODE)
+class Keycode : public std::variant<EKEY_CODE, wchar_t> {
+	using super = std::variant<EKEY_CODE, wchar_t>;
+public:
+	Keycode() : Keycode(KEY_KEY_CODES_COUNT, L'\0') {}
+
+	Keycode(EKEY_CODE code, wchar_t ch)
+	{
+		emplace(code, ch);
+	}
+
+	using super::emplace;
+	void emplace(EKEY_CODE code, wchar_t ch)
+	{
+		if (isValid(code))
+			emplace<EKEY_CODE>(code);
+		else
+			emplace<wchar_t>(ch);
+	}
+
+	static bool isValid(EKEY_CODE code)
+	{
+		return code > 0 && code < KEY_KEY_CODES_COUNT;
+	}
+};
+
 } // end namespace irr