From b089612d92be2c96d9a6eb73322dc53b86baafca Mon Sep 17 00:00:00 2001
From: Adam Mayer <phooky@gmail.com>
Date: Tue, 2 Jan 2018 14:00:22 -0500
Subject: [PATCH] adding quick script for ripping fonts in raw format for use
 in cairo generators

---
 roms/font_to_pickled_dict.py | 48 ++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100755 roms/font_to_pickled_dict.py

diff --git a/roms/font_to_pickled_dict.py b/roms/font_to_pickled_dict.py
new file mode 100755
index 0000000..c71399a
--- /dev/null
+++ b/roms/font_to_pickled_dict.py
@@ -0,0 +1,48 @@
+#!/usr/bin/python3
+"""
+Extract the fonts and create pickled dictionaries mapping characters to the raw binary
+strings representing each entry. Parsing these strings is done in the client code.
+"""
+
+import struct
+import pickle
+
+alpha_ft_start = 0x2569
+point_ft_start = 0x3153
+
+f = open("ROM.bin","rb")
+data = f.read()
+
+def eot(ft, off):
+    "Returns true if the offset is at the end of the table."
+    # Presumes that every table terminates in 0xff
+    return data[ft + off*2] == 0xff
+
+def get_char(ft,off):
+    "Returns the character data (sans terminating 0xff)"
+    achar = chr(off+0x20)
+    o1 = ft + (off*2)
+    o2 = (data[o1+1]*256) + data[o1]
+    o3 = o2
+    while data[o3] != 0xff:
+        o3 += 1
+    return data[o2:o3]    
+
+
+def build_char_dict(ft, first_char=0):
+    offset = 0
+    d = {}
+    while not eot(ft,offset):
+        cur_char = chr(offset+first_char)
+        d[cur_char] = get_char(ft,offset)
+        offset += 1
+    return d
+
+def pickle_font(path, ft, first_char=0):
+    f = open(path,"wb")
+    d = build_char_dict(ft,first_char)
+    pickle.dump(d,f)
+
+pickle_font("a410_chars.pickle",alpha_ft_start,ord(' '))
+pickle_font("a410_points.pickle",point_ft_start)
+