Store character mappings in PROGMEM

library.properties

@@ -2,8 +2,8 @@ name=LiquidCrystal I2C Multilingual
 version=2.0.2
 author=Loc P. Le
 maintainer=Loc P. Le <phuocloc@gmail.com>
-sentence=For printing multilingual UTF8 strings (French, Russian, Vietnamese, Katakana, etc.) to LCD1602, LCD2004, etc. via I2C.
-paragraph=Automatically move down and pause when printing long text. This is subclass of LiquidCrystal_I2C.
+sentence=Display multilingual text on LCD text displays via I2C.
+paragraph=Displays multilingual strings (French, Russian, Vietnamese, Katakana, etc.) encoded in UTF-8 on LCD text displays, e.g. LCD1602 and LCD2004, via I2C.
 category=Display
 url=https://github.com/locple/LCDI2C_Multilingual
 architectures=avr,esp8266,esp32

src/Custom/Symbols.cpp

@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: MIT */
+
+#include "Symbols.h"
+
+PROGMEM const CustomCharacterType SymbolCustomLetters[SymbolCustomLetterNum] = {
+    {0x00B0,
+     {0b00000000, 0b01100000, 0b10010000, 0b10010000,
+      0b01100000}}, // ° (degreeF symbol)
+    {0x20AC,
+     {0b00101000, 0b01111100, 0b10101010, 0b10101010,
+      0b10000010}} // € (Euro sign)
+};
+
+uint8_t getAlternativeLetter(uint16_t c) {
+  switch (c) {
+  case 0x00B0: // degree symbol
+    return 0xDF;
+  case 0x20AC: // Euro sign
+    return 0x45;
+  default: // Input code point is not symbols!
+    return '*';
+  }
+}

src/Custom/Symbols.h

@@ -13,34 +13,24 @@
 #ifndef Custom_Symbols_h
 #define Custom_Symbols_h
 
-#include "../base/LCDI2C_Types.h"
 #include "../base/LCDI2C_Custom.h"
+#include "../base/LCDI2C_Types.h"
+#include <Arduino.h>
 
 const uint8_t SymbolCustomLetterNum = 2;
 // List of custom Unicode characters
-CustomCharacterType SymbolCustomLetters [SymbolCustomLetterNum] = {
-  {0x00B0, {0b00000000,0b01100000,0b10010000,0b10010000,0b01100000}},	// ° (degree symbol)
-  {0x20AC, {0b00101000,0b01111100,0b10101010,0b10101010,0b10000010}}	// € (Euro sign)
-};
+extern PROGMEM const CustomCharacterType
+    SymbolCustomLetters[SymbolCustomLetterNum];
 
 class CustomizedSymbols : public CustomizedLanguage {
 public:
-  CustomizedSymbols(LCDI2C_UTF8* lcd) : CustomizedLanguage(lcd) {
+  CustomizedSymbols(LCDI2C_UTF8 *lcd) : CustomizedLanguage(lcd) {
     CustomLetterNum = SymbolCustomLetterNum;
     CustomLetters = SymbolCustomLetters;
   }
 
 protected:
-  uint8_t getAlternativeLetter(uint16_t c) override {
-    switch (c) {
-      case 0x00B0:  // degree symbol
-        return 0xDF;
-      case 0x20AC:  // Euro sign
-        return 0x45;
-      default:  // Input code point is not symbols!
-        return '*';
-    }
-  }
+  uint8_t getAlternativeLetter(uint16_t c) override;
 };
 
-#endif  // Custom_Symbols_h
+#endif // Custom_Symbols_h