Started working on fonts

1 files changed, 178 insertions, 0 deletions

diff --git a/src/font.c b/src/font.c
new file mode 100644
index 0000000..999c3da
--- /dev/null
+++ b/src/font.c
@@ -0,0 +1,178 @@
+#include "font.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#define FILE_NAME_SIZE 300
+
+void free_sprite_font(sprite_font* font) {
+  free(font->characters);
+  SDL_DestroyTexture(font->spritesheet);
+
+  memset(font, 0, sizeof(sprite_font));
+}
+
+int get_string_parameter(const char* line, const char* parameter, const char** start) {
+  *start = strstr(line, parameter);
+  if ((*start) == NULL)
+    return -1;
+
+  *start += strlen(parameter);
+  if ((*start)[0] != '\"') {
+    return -1;
+  }
+
+  int length = 0;
+  while ((*start)[length+1] != '\0' && (*start)[length+1] != '\"') length++;
+
+  (*start)++;
+  return length;
+}
+
+char parse_character_tag(const char* character_tag) {
+  if (strncmp(character_tag, "space", 5) == 0)
+    return ' ';
+
+  return character_tag[0];
+}
+
+bool get_int_parameter(const char* line, const char* parameter, int* value) {
+  const char* start = strstr(line, parameter);
+  if (start == NULL) {
+    return false;
+  }
+  start += strlen(parameter);
+
+  int c = 0;
+  bool negative = false;
+
+  if (start[0] == '-') {
+    negative = true;
+    start++;
+  }
+
+  for(int i = 0; start[i] >= '0' && start[i] <= '9'; i++) {
+    c *= 10; c += start[i] - '0';
+  }
+
+  *value = negative ? -c : c;
+  return true;
+}
+
+bool load_sprite_font(const char* filename, sprite_font* font) {
+  if (font->characters || font->spritesheet) {
+    SDL_Log("Trying to reallocate font causing memory leak, exitting!");
+    exit(EXIT_FAILURE);
+  }
+
+  FILE* f = fopen(filename, "r");
+  if (f == NULL) {
+    SDL_Log("Failed to open sprite font file %s, error: %s, exitting!",
+            filename,
+            strerror(errno)
+            );
+    exit(EXIT_FAILURE);
+  }
+
+  char line[PARSER_LINE_SIZE];
+  if (fgets(line, sizeof(line), f) == NULL ||
+      strncmp(line, "info", 4) != 0) {
+    SDL_Log("File %s is not a valid font file, exitting!",
+            filename);
+    fclose(f);
+    exit(EXIT_FAILURE);
+  }
+
+  char font_name[FONT_NAME_SIZE];
+  const char* font_name_start;
+  int font_name_length =
+    SDL_min(get_string_parameter(line, "face=", &font_name_start),
+            FONT_NAME_SIZE-1
+            );
+
+  strncpy(font_name, font_name_start, font_name_length);
+  font_name[font_name_length] = '\0';
+
+  int char_size = 0, char_count = 0;
+  font_char* characters_unarranged = NULL;
+
+  while (fgets(line, PARSER_LINE_SIZE, f) != NULL) {
+
+    if (strncmp(line, "chars", 5) == 0) {
+      int total_char_count;
+
+      if(!get_int_parameter(line, "count=", &total_char_count))
+        continue;
+
+      char_size = total_char_count;
+      characters_unarranged =
+        realloc(characters_unarranged, char_size * sizeof(font_char));
+
+      if (characters_unarranged == NULL) {
+        SDL_Log("Failed to allocate space while loading font %s, error %s, exitting!",
+                filename,
+                strerror(errno));
+        exit(EXIT_FAILURE);
+      }
+    }
+
+    else if (strncmp(line, "char", 4) == 0) {
+      font_char new_font_char;
+
+      int val;
+
+      if (!get_int_parameter(line, "x=", &val))
+        continue;
+      new_font_char.x = val;
+
+      if (!get_int_parameter(line, "y=", &val))
+        continue;
+      new_font_char.y = val;
+
+      if (!get_int_parameter(line, "width=", &val))
+        continue;
+      new_font_char.width = val;
+
+      if (!get_int_parameter(line, "height=", &val))
+        continue;
+      new_font_char.height = val;
+
+      if (!get_int_parameter(line, "xoffset=", &val))
+        continue;
+      new_font_char.x_offset = val;
+
+      if (!get_int_parameter(line, "yoffset=", &val))
+        continue;
+      new_font_char.y_offset = val;
+
+      if (!get_int_parameter(line, "xadvance=", &val))
+        continue;
+      new_font_char.x_advance = val;
+
+      const char* character_tag;
+      if (get_string_parameter(line, "letter=", &character_tag) <= 0)
+        continue;
+      new_font_char.character = parse_character_tag(character_tag);
+
+      if (char_count >= char_size) {
+        char_size = char_count+1;
+        characters_unarranged =
+          realloc(characters_unarranged, char_size * sizeof(font_char));
+      }
+
+      if (characters_unarranged == NULL) {
+        SDL_Log("Failed to allocate space while loading font %s, error %s, exitting!",
+                filename,
+                strerror(errno));
+        exit(EXIT_FAILURE);
+      }
+
+      characters_unarranged[char_count] = new_font_char;
+      char_count++;
+    }
+  }
+
+  fclose(f);
+  return true;
+}