Implement as optional feature LCD_DECIMAL_SMALL_XY

And reduce the function size to simplify

Marlin/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/Cartesio/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/Felix/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/Hephestos/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/Hephestos_2/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/K8200/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/K8400/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/RigidBot/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/SCARA/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/TAZ4/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/WITBOX/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/delta/biv2.5/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/delta/generic/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/delta/kossel_mini/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/delta/kossel_pro/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/delta/kossel_xl/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/makibox/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/example_configurations/tvrrug/Round2/Configuration_adv.h

 // Include a page of printer information in the LCD Main Menu
 //#define LCD_INFO_MENU
 
+// On the Info Screen, display XY with one decimal place when possible
+//#define LCD_DECIMAL_SMALL_XY
+
 #if ENABLED(SDSUPPORT)
 
   // Some RAMPS and other boards don't detect when an SD card is inserted. You can work

Marlin/utility.cpp

     return conv;
   }
 
-  // Convert float to rj string with 1234, _123, -123, _-12, 12.3, _1.2, or -1.2 format
-  char *ftostr4sign(const float& fx) { 
-    int x = fx * 10, xx = abs(x);
-    bool ispos = x >= 0,
-         isten = xx >= 100,
-         ishun = xx >= 1000;
-    if (!isten || (ispos && !ishun)) {
-      // 12.3, _1.2, -1.2
-      conv[0] = ispos ? (isten ? DIGIMOD(xx, 100) : ' ') : '-';
+  #if ENABLED(LCD_DECIMAL_SMALL_XY)
+
+    // Convert float to rj string with 1234, _123, -123, _-12, 12.3, _1.2, or -1.2 format
+    char *ftostr4sign(const float& fx) {
+      int x = fx * 10;
+      if (x <= -100 || x >= 1000) return itostr4sign((int)fx);
+      int xx = abs(x);
+      conv[0] = x < 0 ? '-' : (xx >= 100 ? DIGIMOD(xx, 100) : ' ');
       conv[1] = DIGIMOD(xx, 10);
       conv[2] = '.';
       conv[3] = DIGIMOD(xx, 1);
+      conv[4] = '\0';
+      return conv;
     }
-    else {
-      // 1234, _123, -123, _-12
-      conv[0] = ispos ? (xx >= 10000 ? DIGIMOD(xx, 10000) : ' ') : (ishun ? '-' : ' ');
-      conv[1] = ishun ? DIGIMOD(xx, 1000) : '-';
-      conv[2] = DIGIMOD(xx, 100);
-      conv[3] = DIGIMOD(xx, 10);
-    }
-    conv[4] = '\0';
-    return conv;
-  }
+
+  #endif // LCD_DECIMAL_SMALL_XY
 
   // Convert float to fixed-length string with +123.4 / -123.4 format
   char* ftostr41sign(const float& x) {

Marlin/utility.h

   // Convert float to rj string with 123 or -12 format
   FORCE_INLINE char *ftostr3(const float& x) { return itostr3((int)x); }
 
-  // Convert float to rj string with 1234, _123, 12.3, _1.2, -123, _-12, or -1.2 format
-  char *ftostr4sign(const float& fx);
+  #if ENABLED(LCD_DECIMAL_SMALL_XY)
+    // Convert float to rj string with 1234, _123, 12.3, _1.2, -123, _-12, or -1.2 format
+    char *ftostr4sign(const float& fx);
+  #else
+    // Convert float to rj string with 1234, _123, -123, __12, _-12, ___1, or __-1 format
+    FORCE_INLINE char *ftostr4sign(const float& x) { return itostr4sign((int)x); }
+  #endif
 
 #endif // ULTRA_LCD