add LV_FONT_FMT_TXT_LARGE to support very large fonts

lv_conf_template.h

@@ -275,6 +275,11 @@ typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the i
 /*Always set a default font from the built-in fonts*/
 #define LV_FONT_DEFAULT        &lv_font_roboto_16
 
+/* Enable it if you have fonts with a lot of characters.
+ * The limit depends on the font size, font face and bpp
+ * but with > 10,000 characters if you see issues probably you need to enable it.*/
+#define LV_FONT_FMT_TXT_LARGE   0
+
 /*Declare the type of the user data of fonts (can be e.g. `void *`, `int`, `struct`)*/
 typedef void * lv_font_user_data_t;
 

src/lv_conf_checker.h

@@ -385,6 +385,13 @@
 #define LV_FONT_DEFAULT        &lv_font_roboto_16
 #endif
 
+/* Enable it if you have fonts with a lot of characters.
+ * The limit depends on the font size, font face and bpp
+ * but with > 10,000 characters if you see issues probably you need to enable it.*/
+#ifndef LV_FONT_FMT_TXT_LARGE
+#define LV_FONT_FMT_TXT_LARGE   0
+#endif
+
 /*Declare the type of the user data of fonts (can be e.g. `void *`, `int`, `struct`)*/
 
 /*=================

src/lv_font/lv_font_fmt_txt.h

@@ -35,9 +35,13 @@ extern "C" {
 /** This describes a glyph. */
 typedef struct
 {
+#if LV_FONT_FMT_TXT_LARGE == 0
     uint32_t bitmap_index : 20;     /**< Start index of the bitmap. A font can be max 1 MB. */
-    uint32_t adv_w :12;             /**< Draw the next glyph after this width. 12.4 format (real_value * 16 is stored). */
+    uint32_t adv_w :12;             /**< Draw the next glyph after this width. 8.4 format (real_value * 16 is stored). */
-
+#else
+    uint32_t bitmap_index;          /**< Start index of the bitmap. A font can be max 4 GB. */
+    uint32_t adv_w;                 /**< Draw the next glyph after this width. 28.4 format (real_value * 16 is stored). */
+#endif
     uint8_t box_w;                  /**< Width of the glyph's bounding box*/
     uint8_t box_h;                  /**< Height of the glyph's bounding box*/
     int8_t ofs_x;                   /**< x offset of the bounding box*/