cmake: convert bmp images to c headers using python script

A pure CMake script was too slow

cmake/xxd.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python
+
+import argparse
+import os
+import pathlib
+import re
+
+def main():
+    parser = argparse.ArgumentParser(allow_abbrev=False, description="Convert file into includable C header")
+    parser.add_argument("--in", "-i", type=pathlib.Path, metavar="INPUT", dest="input", required=True, help="Input file")
+    parser.add_argument("--out", "-o", type=pathlib.Path, metavar="OUTPUT", dest="output", required=True, help="Output header")
+    parser.add_argument("--columns", type=int, default=12, help="Column count")
+    args = parser.parse_args()
+
+    t = pathlib.Path()
+    varname, _ = re.subn("[^a-zA-Z0-9]", "_", str(args.input.name))
+
+    binary_data = args.input.open("rb").read()
+
+    with open(args.output, "w") as fout:
+        fout.write("unsigned char {}[] = {{\n".format(varname))
+        bytes_written = 0
+        while bytes_written < len(binary_data):
+            col = bytes_written % args.columns
+            if col == 0:
+                fout.write("  ")
+            column_data = binary_data[bytes_written:bytes_written+args.columns]
+            fout.write(", ".join("0x{:02x}".format(d) for d in column_data))
+            bytes_written += len(column_data)
+            if bytes_written < len(binary_data):
+                fout.write(",\n")
+            else:
+                fout.write("\n")
+        fout.write("}};\nunsigned int {}_len = {:d};\n".format(varname, len(binary_data)))
+
+if __name__ == "__main__":
+    raise SystemExit(main())