LVGL Font Compatibility (gfx_font_lvgl)

This module provides compatibility functions for loading and using LVGL fonts in the ESP Emote GFX framework.

Functions

gfx_font_lv_load_from_binary()

Load an LVGL font from binary data.

lv_font_t *gfx_font_lv_load_from_binary(uint8_t *bin_addr);

Parameters:

• bin_addr - Pointer to binary data containing lv_font_t structure

Returns:

• Pointer to loaded lv_font_t on success, NULL on failure

Note:

This function is useful when loading LVGL fonts from binary files or memory-mapped regions.

gfx_font_lv_delete()

Delete an LVGL font created from binary data.

void gfx_font_lv_delete(lv_font_t *font);

Parameters:

• font - Pointer to lv_font_t to delete

Note:

Use this function to free resources when you’re done with a font loaded via gfx_font_lv_load_from_binary().

Usage with Label Widget

LVGL fonts can be used directly with the label widget:

// Using a compiled LVGL font
extern const lv_font_t font_puhui_16_4;
gfx_obj_t *label = gfx_label_create(handle);
gfx_label_set_font(label, (gfx_font_t)&font_puhui_16_4);

// Using a font loaded from binary
uint8_t *font_binary = ...;  // Font binary data
lv_font_t *font = gfx_font_lv_load_from_binary(font_binary);
if (font) {
    gfx_label_set_font(label, (gfx_font_t)font);
    // ... use font ...
    gfx_font_lv_delete(font);
}

Font Format

LVGL fonts are typically compiled into C arrays using the LVGL font converter tools. The fonts contain:

• Glyph bitmap data

• Character mapping information

• Font metrics (line height, baseline, etc.)

The ESP Emote GFX framework is compatible with standard LVGL font structures, allowing you to use fonts created with LVGL tools directly.