# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1496095649 -7200
# Node ID 5b587a1f95630deaedb36dc86cece3229dcfef16
# Parent  d7298bd864252ecdae537bd434a983600e270dfc
Added a tool to generate font definitions from GNU Unifont definitions.
Added assembly language directives to the image tool output.

diff -r d7298bd86425 -r 5b587a1f9563 tools/makefont.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tools/makefont.py	Tue May 30 00:07:29 2017 +0200
@@ -0,0 +1,154 @@
+#!/usr/bin/env python
+
+"""
+Convert GNU Unifont format definitions into data statements for GNU as.
+
+Copyright (C) 2017 Paul Boddie <paul@boddie.org.uk>
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+from os.path import split
+import sys
+
+def convert_font(fin, fout, points, missing=32):
+
+    """
+    Convert the font obtained via 'fin' to an assembly language representation,
+    writing to 'fout' the characters for the chosen sequence of 'points'.
+
+    A table of offsets is written to permit each character to be found in the
+    generated data.
+
+    If 'missing' is specified, the character of the given value will be used
+    for missing character data.
+    """
+
+    points.sort()
+    base = points[0]
+    limit = points[-1]
+
+    # Store the offset of each chosen character.
+
+    table = []
+    offset = 0
+
+    # Search for each character until no more remain to be found.
+
+    index = 0
+    end = len(points)
+
+    print >>fout, """\
+.globl fontchars
+.globl fonttable
+.globl fontbase
+.globl fontlimit
+
+.section .flash, "a"
+
+fontchars:"""
+
+    line = fin.readline()
+
+    while line and index < end:
+
+        # Obtain the code point and data.
+
+        point, data = line.rstrip().split(":")
+        point = int(point, 16)
+
+        # Add null offsets for missing characters.
+
+        i = len(table) + base
+        while i < point:
+            table.append(None)
+            i += 1
+
+        # Add a null offset for unselected characters.
+
+        if point < points[index]:
+            if point >= base:
+                table.append(None)
+            line = fin.readline()
+            continue
+
+        # Obtain the byte values from the data.
+
+        bytes = []
+        i = 0
+        while i < len(data):
+            bytes.append("0x%s" % data[i:i+2])
+            i += 2
+
+        # Add an offset for the character.
+
+        table.append(offset)
+        offset += len(bytes)
+
+        # Write the character details.
+
+        print >>fout, "/* %s */" % point
+        print >>fout, ".byte", ", ".join(bytes)
+
+        index += 1
+        line = fin.readline()
+
+    # Add a final offset to mark the end of the data.
+
+    table.append(offset)
+
+    # Write the offset table.
+
+    print >>fout, """
+fonttable:"""
+
+    for offset in table:
+        if offset is None:
+            offset = table[missing - base]
+        print >>fout, ".word %d" % offset
+
+    print >>fout, """
+fontbase:
+.byte %d
+
+fontlimit:
+.byte %d""" % (base, limit)
+
+# Main program.
+
+if __name__ == "__main__":
+
+    # Test options.
+
+    if "--help" in sys.argv or len(sys.argv) < 3:
+        basename = split(sys.argv[0])[1]
+        print >>sys.stderr, """\
+Usage:
+
+%s <input filename> <output filename>
+""" % basename
+        sys.exit(1)
+
+    base = 32
+    points = range(32, 127)
+
+    input_filename, output_filename = sys.argv[1:3]
+    fin = open(input_filename)
+    fout = open(output_filename, "w")
+    try:
+        convert_font(fin, fout, points, base)
+    finally:
+        fin.close()
+        fout.close()
+
+# vim: tabstop=4 expandtab shiftwidth=4
diff -r d7298bd86425 -r 5b587a1f9563 tools/makeimage.py
--- a/tools/makeimage.py	Sun May 28 23:11:05 2017 +0200
+++ b/tools/makeimage.py	Tue May 30 00:07:29 2017 +0200
@@ -39,6 +39,12 @@
 
     f = open(output_filename, "w")
     try:
+        print >>f, """\
+.globl screendata
+
+.section .flash, "a"
+"""
+
         word = []
         y = 0