1 files changed, 24 insertions, 0 deletions
diff --git a/fmdsp/font_rom.c b/fmdsp/font_rom.c
new file mode 100644
index 0000000..de6bc19
--- /dev/null
+++ b/fmdsp/font_rom.c
@@ -0,0 +1,24 @@
+#include "font.h"
+
+static const void *font_rom_get(const struct fmdsp_font *font,
+                                uint16_t jis, enum fmdsp_font_type type) {
+  const uint8_t *fontdata = font->data;
+  const uint8_t *fontptr;
+  if (type == FMDSP_FONT_ANK) {
+    fontptr =  fontdata + 0x800 + (jis<<4);
+  } else {
+    uint8_t row = jis >> 8;
+    uint8_t cell = jis;
+    fontptr = fontdata + (0x800 + (0x60*16*2*(row-0x20)) + (cell<<5));
+    if (type == FMDSP_FONT_JIS_RIGHT) fontptr += 16;
+  }
+  if ((fontptr + (16*16/8)) > (fontdata + FONT_ROM_FILESIZE)) fontptr = 0;
+  return fontptr;
+}
+
+void fmdsp_font_from_font_rom(struct fmdsp_font *font, const void *data) {
+  font->data = data;
+  font->width_half = 8;
+  font->height = 16;
+  font->get = font_rom_get;
+}