Some changes to support binary fonts without the kernel table.

lvgl.h

@@ -31,6 +31,7 @@ extern "C" {
 #include "src/lv_themes/lv_theme.h"
 
 #include "src/lv_font/lv_font.h"
+#include "src/lv_font/lv_font_loader.h"
 #include "src/lv_font/lv_font_fmt_txt.h"
 #include "src/lv_misc/lv_printf.h"
 

src/lv_font/lv_font_loader.c

@@ -6,7 +6,6 @@
 /*********************
  *      INCLUDES
  *********************/
-#if LV_USE_FILESYSTEM
 
 #include <stdint.h>
 #include <stdbool.h>
@@ -15,6 +14,8 @@
 #include "../lv_misc/lv_fs.h"
 #include "lv_font_loader.h"
 
+#if LV_USE_FILESYSTEM
+
 
 /**********************
  *      TYPEDEFS
@@ -101,7 +102,7 @@ lv_font_t * lv_font_load(const char * font_name)
 
     if (!success)
     {
-        LV_LOG_WARN("Error opening font file: %s\n", font_name);
+        LV_LOG_WARN("Error loading font file: %s\n", font_name);
         lv_font_free(font);
         font = NULL;
     }
@@ -220,7 +221,7 @@ static int read_label(lv_fs_file_t *fp, int start, const char *label)
     if(lv_fs_read(fp, &length, 4, NULL) != LV_FS_RES_OK
             || lv_fs_read(fp, buf, 4, NULL) != LV_FS_RES_OK
             || memcmp(label, buf, 4) != 0) {
-        LV_LOG_WARN("Error reading '%s'.", label);
+        LV_LOG_WARN("Error reading '%s' label.", label);
         return -1;
     }
 
@@ -408,20 +409,31 @@ static bool lvgl_load_font(lv_fs_file_t * fp, lv_font_t * font)
 
         bit_iterator_t bit_it = init_bit_iterator(fp);
 
-        if(font_header.advance_width_bits == 0) {
+        /*
+         * TODO: understand how to interpret advance_width_format
+         * When it is set to zero, in my understanding should be used the default value,
+         * and no data should be written on the advance_width, but it is not occurring.
+         *
+         * The following code is not working for most monospaced fonts.
+         */
+
+        /*if(font_header.advance_width_bits == 0) {
             gdsc->adv_w = font_header.default_advance_width;
         }
-        else {
+        else */ {
-            gdsc->adv_w = read_bits(&bit_it, font_header.advance_width_bits, &res);
-            if(res != LV_FS_RES_OK) {
-                failed = true;
-                break;
-            }
-
-            /* TODO: understand how to interpret advance_width_format */
             if(font_header.advance_width_format == 0) { /* uint */
+                gdsc->adv_w = 16 * read_bits(&bit_it, 4, &res); // TODO: review the number of bits that should be read
+                if(res != LV_FS_RES_OK) {
+                    failed = true;
+                    break;
+                }
             }
             else if(font_header.advance_width_format == 1) { /* unsigned with 4 bits fractional part */
+                gdsc->adv_w = read_bits(&bit_it, font_header.advance_width_bits, &res);
+                if(res != LV_FS_RES_OK) {
+                    failed = true;
+                    break;
+                }
             }
             else {
                 LV_LOG_WARN("error unknown advance_width_format");
@@ -525,8 +537,11 @@ static bool lvgl_load_font(lv_fs_file_t * fp, lv_font_t * font)
         return false;
     }
 
-    if(lv_fs_seek(fp, glyph_start + glyph_length) != LV_FS_RES_OK) {
+    if (font_header.tables_count < 4) {
-        return false;
+        font_dsc->kern_dsc = NULL;
+        font_dsc->kern_classes = 0;
+        font_dsc->kern_scale = 0;
+        return true;
     }
 
     uint32_t kern_start = glyph_start + glyph_length;

tests/lv_test_core/lv_test_font_loader.c

@@ -44,8 +44,8 @@ static int compare_fonts(lv_font_t * f1, lv_font_t * f2);
 
 void lv_test_font_loader(void)
 {
-    lv_font_t * font = lv_font_load("f:lv_font_montserrat_12.bin");
+    lv_font_t * montserrat_12_bin = lv_font_load("f:lv_font_montserrat_12.bin");
-    compare_fonts(&lv_font_montserrat_12, font);
+    compare_fonts(&lv_font_montserrat_12, montserrat_12_bin);
 }
 
 static int compare_fonts(lv_font_t * f1, lv_font_t * f2)
@@ -109,22 +109,26 @@ static int compare_fonts(lv_font_t * f1, lv_font_t * f2)
     // kern_dsc
     lv_font_fmt_txt_kern_classes_t * kern1 = (lv_font_fmt_txt_kern_classes_t *) dsc1->kern_dsc;
     lv_font_fmt_txt_kern_classes_t * kern2 = (lv_font_fmt_txt_kern_classes_t *) dsc2->kern_dsc;
+    if (kern1 != NULL && kern2 != NULL) {
+        lv_test_assert_int_eq(kern1->right_class_cnt, kern2->right_class_cnt, "right_class_cnt");
+        lv_test_assert_int_eq(kern1->left_class_cnt, kern2->left_class_cnt, "left_class_cnt");
 
-    lv_test_assert_int_eq(kern1->right_class_cnt, kern2->right_class_cnt, "right_class_cnt");
+        for(int i = 0; i < kern1->left_class_cnt; ++i) {
-    lv_test_assert_int_eq(kern1->left_class_cnt, kern2->left_class_cnt, "left_class_cnt");
+            lv_test_assert_int_eq(kern1->left_class_mapping[i],
+                    kern2->left_class_mapping[i], "left_class_mapping");
+        }
+        for(int i = 0; i < kern1->right_class_cnt; ++i) {
+            lv_test_assert_int_eq(kern1->right_class_mapping[i],
+                    kern2->right_class_mapping[i], "right_class_mapping");
+        }
 
-    for(int i = 0; i < kern1->left_class_cnt; ++i) {
+        for(int i = 0; i < kern1->right_class_cnt * kern1->left_class_cnt; ++i) {
-        lv_test_assert_int_eq(kern1->left_class_mapping[i],
+            lv_test_assert_int_eq(kern1->class_pair_values[i],
-                      kern2->left_class_mapping[i], "left_class_mapping");
+                    kern2->class_pair_values[i], "class_pair_values");
+        }
     }
-    for(int i = 0; i < kern1->right_class_cnt; ++i) {
+    else {
-        lv_test_assert_int_eq(kern1->right_class_mapping[i],
+        lv_test_assert_ptr_eq(kern1, kern2, "kern");
-                      kern2->right_class_mapping[i], "right_class_mapping");
-    }
-
-    for(int i = 0; i < kern1->right_class_cnt * kern1->left_class_cnt; ++i) {
-        lv_test_assert_int_eq(kern1->class_pair_values[i],
-                      kern2->class_pair_values[i], "class_pair_values");
     }
 
     // TODO: glyph_bitmap