Handle codepoints outside the BMP

Author: Wires77

engine/system/win/sys_console.cpp

@@ -298,7 +298,16 @@ void sys_console_c::Print(std::u32string_view string_view_text)
 			b+= escLen - 1;
 		} else {
 			// Add character
-			*(p++) = (char16_t)text[b];
+			if (text[b] > INT16_MAX) { // Outside the BMP
+				char16_t high_surrogate = ((text[b] - 0x10000) >> 10) + 0xD800;
+				char16_t low_surrogate = ((text[b] - 0x10000) << 10) + 0xDC00;
+				*(p++) = high_surrogate;
+				*(p++) = low_surrogate;
+			}
+			else {
+				*(p++) = (char16_t)text[b];
+			}
+			
 		}
 	}
 	winText[len] = 0;