Long awaited PF2 font zooming ("scaling"), fixes:

Frontend will connect to printer only right before printing
Frontend option layout organized & optimized
Backend supress useless warnings

README.md

@@ -48,7 +48,7 @@ Currently:
   - and also Android!
 
 - Free, as in [freedom](https://www.gnu.org/philosophy/free-sw.html)!
-  - Unlike the "original" proprietary app,  
+  - Unlike those proprietary "apps" around,  
     this project is for everyone that concerns *open-mind and freedom*!
 
 - and Fun!
@@ -120,7 +120,7 @@ Copyright © 2021-2022 NaitLee Soft. Some rights reserved.
 See file `COPYING`, `LICENSE`, and detail of used JavaScript in file `www/jslicense.html`
 
 Particularly, `printer.py`, `server.py` and `main.js` are released under GNU GPL 3.  
-Excluding contributions of other people (which probably have their own copyright) and possible third-party dependencies, all other parts are in Public Domain (CC0).
+All other parts, except which have special statements, are in Public Domain (CC0).
 
 --------
 
@@ -134,9 +134,12 @@ Also interested in code development? See [development.md](development.md)!
 ### Credits
 
 - Of course, Python & the Web!
-- [Bleak](https://bleak.readthedocs.io/en/latest/) BLE lib! The overall Hero!
+- [Bleak](https://bleak.readthedocs.io/en/latest/) Bluetooth-Low-Energy library! The overall Hero!
 - [roddeh-i18n](https://github.com/roddeh/i18njs), the current built-in i18n is inspired by this
+- [PF2 font](http://grub.gibibit.com/New_font_format), great minimal raster font idea
+- ImageMagick & Ghostscript, never mention other if something useful is already in one's system
 - [python-for-android](https://python-for-android.readthedocs.io/en/latest/), though there are some painful troubles
 - [AdvancedWebView](https://github.com/delight-im/Android-AdvancedWebView) for saving my life from Java
 - Stack Overflow & the whole Internet, you let me know Android `Activity` all from beginning
+  ... and many other helpful ideas as well
 - ... Everyone is Awesome!

TODO

@@ -11,6 +11,8 @@ Note: not ordered. do whatever I/you want
 + Try to implement enough without more dependencies
 + ...
 
+? Optimize PF2 text printing? It seems a bit slow (in algorithm).
+? Built-in PostScript? (Even if very basic)
 ? Data compression for GB03. Optional
 ? Put Android APP on F-Droid? But it needs automatic build system...
   Android guys can help this!

printer.py

@@ -275,6 +275,7 @@ class PrinterDriver(Commander):
     flip_v: bool = False
     wrap: bool = False
     rtl: bool = False
+    font_scale: int = 1
 
     energy: int = None
     quality: int = 24
@@ -468,7 +469,8 @@ def _print_text(self, file: io.BufferedIOBase):
         text_io = io.TextIOWrapper(file, encoding='utf-8')
         if self.text_canvas is None:
             self.text_canvas = TextCanvas(paper_width, wrap=self.wrap,
-                rtl=self.rtl, font_path=self.font_family + '.pf2')
+                    rtl=self.rtl, font_path=self.font_family + '.pf2',
+                    scale=self.font_scale)
         # with stdin you maybe trying out a typewriter
         # so print a "ruler", indicating max characters in one line
         if file is sys.stdin.buffer:
@@ -480,16 +482,16 @@ def _print_text(self, file: io.BufferedIOBase):
                 width_stats[char] = pf2[char].width
             average = pf2.point_size // 2
             if (width_stats[' '] == width_stats['i'] ==
-                width_stats['m'] == width_stats['M']):
+                    width_stats['m'] == width_stats['M']):
                 # monospace
                 average = width_stats['A']
             else:
                 # variable width, use a rough average
                 average = (width_stats['a'] + width_stats['A'] +
-                           width_stats['0'] + width_stats['+']) // 4
+                        width_stats['0'] + width_stats['+']) // 4
             # ruler
             info('-------+' * (paper_width // average // 8) +
-                 '-' * (paper_width // average % 8))
+                    '-' * (paper_width // average % 8))
         self._prepare()
         printer_data = PrinterData(paper_width)
         buffer = io.BytesIO()
@@ -502,7 +504,7 @@ def _print_text(self, file: io.BufferedIOBase):
                     buffer.write(data)
                     line_count += 1
                 flip(buffer, self.text_canvas.width, self.text_canvas.height * line_count,
-                     self.flip_h, self.flip_v, overwrite=True)
+                        self.flip_h, self.flip_v, overwrite=True)
                 while chunk := buffer.read(paper_width // 8):
                     printer_data.write(chunk)
                     if self.dry_run:
@@ -550,17 +552,17 @@ def magick_text(stdin, image_width, font_size, font_family):
     'Pipe an io to ImageMagick for processing text to image, return output io'
     read_fd, write_fd = os.pipe()
     subprocess.Popen([_MagickExe, '-background', 'white', '-fill', 'black',
-        '-size', f'{image_width}x', '-font', font_family, '-pointsize', str(font_size),
-        'caption:@-', 'pbm:-'],
-        stdin=stdin, stdout=io.FileIO(write_fd, 'w'))
+            '-size', f'{image_width}x', '-font', font_family, '-pointsize',
+            str(font_size), 'caption:@-', 'pbm:-'],
+            stdin=stdin, stdout=io.FileIO(write_fd, 'w'))
     return io.FileIO(read_fd, 'r')
 
 def magick_image(stdin, image_width, dither):
     'Pipe an io to ImageMagick for processing "usual" image to pbm, return output io'
     read_fd, write_fd = os.pipe()
     subprocess.Popen([_MagickExe, '-', '-fill', 'white', '-opaque', 'transparent',
-        '-resize', f'{image_width}x', '-dither', dither, '-monochrome', 'pbm:-'],
-        stdin=stdin, stdout=io.FileIO(write_fd, 'w'))
+            '-resize', f'{image_width}x', '-dither', dither, '-monochrome', 'pbm:-'],
+            stdin=stdin, stdout=io.FileIO(write_fd, 'w'))
     return io.FileIO(read_fd, 'r')
 
 class HelpFormatterI18n(argparse.HelpFormatter):
@@ -607,29 +609,29 @@ def _main():
     )
     # TODO: group some switches to dedicated help
     parser.add_argument('-h', '--help', action='store_true',
-                        help=i18n('show-this-help-message'))
+            help=i18n('show-this-help-message'))
     parser.add_argument('file', default='-', metavar='File', type=str,
-                        help=i18n('path-to-input-file-dash-for-stdin'))
+            help=i18n('path-to-input-file-dash-for-stdin'))
     parser.add_argument('-s', '--scan', metavar='Time[,XY01[,MacAddress]]', default='4', type=str,
-                        help=i18n('scan-for-a-printer'))
+            help=i18n('scan-for-a-printer'))
     parser.add_argument('-c', '--convert', metavar='text|image', type=str, default='',
-                        help=i18n('convert-input-image-with-imagemagick'))
+            help=i18n('convert-input-image-with-imagemagick'))
     parser.add_argument('-p', '--image', metavar='flip|fliph|flipv', type=str, default='',
-                        help=i18n('image-printing-options'))
+            help=i18n('image-printing-options'))
     parser.add_argument('-t', '--text', metavar='Size[,FontFamily][,pf2][,nowrap][,rtl]', type=str,
-                        default='', help=i18n('text-printing-mode-with-options'))
+            default='', help=i18n('text-printing-mode-with-options'))
     parser.add_argument('-e', '--energy', metavar='0.0-1.0', type=float, default=None,
-                        help=i18n('control-printer-thermal-strength'))
+            help=i18n('control-printer-thermal-strength'))
     parser.add_argument('-q', '--quality', metavar='1-4', type=int, default=3,
-                        help=i18n('print-quality'))
+            help=i18n('print-quality'))
     parser.add_argument('-d', '--dry', action='store_true',
-                        help=i18n('dry-run-test-print-process-only'))
+            help=i18n('dry-run-test-print-process-only'))
     parser.add_argument('-f', '--fake', metavar='XY01', type=str, default='',
-                        help=i18n('virtual-run-on-specified-model'))
+            help=i18n('virtual-run-on-specified-model'))
     parser.add_argument('-m', '--dump', action='store_true',
-                        help=i18n('dump-the-traffic'))
+            help=i18n('dump-the-traffic'))
     parser.add_argument('-n', '--nothing', action='store_true',
-                        help=i18n('do-nothing'))
+            help=i18n('do-nothing'))
 
     if len(sys.argv) < 2 or '-h' in sys.argv or '--help' in sys.argv:
         parser.print_help()
@@ -644,6 +646,10 @@ def _main():
     identifier = ','.join(scan_param[1:])
     if args.energy is not None:
         printer.energy = int(args.energy * 0xff)
+    elif args.convert == 'text' or args.text:
+        printer.energy = 96
+    else:
+        printer.energy = 64
     if args.quality is not None:
         printer.quality = 4 * (args.quality + 5)
 
@@ -665,32 +671,22 @@ def _main():
 
     info(i18n('cat-printer'))
 
-    if args.dry:
-        info(i18n('dry-run-test-print-process-only'))
-        printer.dry_run = True
-    if args.fake:
-        printer.fake = True
-        printer.model = Models[args.fake]
-    else:
-        info(i18n('connecting'))
-        printer.scan(identifier, use_result=True)
-    printer.dump = args.dump
-
-    mode = 'pbm'
-
     if args.file == '-':
         file = sys.stdin.buffer
     else:
         file = open(args.file, 'rb')
 
+    mode = 'pbm'
+
     if args.text:
         info(i18n('text-printing-mode'))
         printer.font_family = font_family or 'font'
         if 'pf2' not in text_param:
             # TODO: remove hardcoded width
             file = magick_text(file, 384,
-                font_size, font_family)
+                    font_size, font_family)
         else:
+            printer.font_scale = font_size
             mode = 'text'
     elif args.convert:
         file = magick_image(file, 384, (
@@ -699,6 +695,17 @@ def _main():
             else 'FloydSteinberg')
         )
 
+    if args.dry:
+        info(i18n('dry-run-test-print-process-only'))
+        printer.dry_run = True
+    if args.fake:
+        printer.fake = True
+        printer.model = Models[args.fake]
+    else:
+        info(i18n('connecting'))
+        printer.scan(identifier, use_result=True)
+    printer.dump = args.dump
+
     if args.nothing:
         global Printer
         Printer = printer

printer_lib/pf2.py

@@ -29,6 +29,7 @@ def int16be(b: bytes):
     u = uint16be(b)
     return u - ((u >> 15 & 0b1) << 16)
 
+
 class Character():
     'A PF2 character'
 
@@ -39,6 +40,11 @@ class Character():
     device_width: int
     bitmap_data: bytes
 
+    def get_bit(self, x, y):
+        'Get the bit at (x, y) of this character\'s raster glyph'
+        char_byte = (self.width * y + x) // 8
+        char_bit = 7 - (self.width * y + x) % 8
+        return self.bitmap_data[char_byte] & (0b1 << char_bit)
 
 class PF2():
     'The PF2 class, for serializing a PF2 font file'
@@ -133,3 +139,49 @@ def get_char(self, char: str):
 
     def __del__(self):
         self.data_io.close()
+
+
+class CharacterS(Character):
+    'A "scaled" character'
+
+    scale: int = 1
+
+    def get_bit(self, x, y):
+        'Get the bit at (x, y) of this character\'s raster glyph'
+        scale = self.scale
+        width = self.width // scale
+        x //= scale
+        y //= scale
+        char_byte = (width * y + x) // 8
+        char_bit = 7 - (width * y + x) % 8
+        return (self.bitmap_data[char_byte] &
+                (0b1 << char_bit)) >> char_bit
+
+class PF2S(PF2):
+    'PF2 class with glyph scaling support'
+
+    scale: int = 1
+
+    def __init__(self, *args, scale: int=1, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.scale = scale
+        self.point_size *= scale
+        self.max_width *= scale
+        self.max_height *= scale
+        self.ascent *= scale
+        self.descent *= scale
+
+    def get_char(self, char):
+        scale = self.scale
+        char = super().get_char(char)
+        chars = CharacterS()
+        chars.scale = scale
+        chars.width = char.width * scale
+        chars.height = char.height * scale
+        chars.device_width = char.device_width * scale
+        chars.x_offset = char.x_offset * scale
+        chars.y_offset = char.y_offset * scale
+        chars.bitmap_data = char.bitmap_data
+        return chars
+
+    __getitem__ = get_char

printer_lib/text_print.py

@@ -1,6 +1,6 @@
 'Things used by Text Printing feature'
 
-from .pf2 import PF2
+from .pf2 import PF2S
 
 class TextCanvas():
     'Canvas for text printing, requires PF2 lib'
@@ -9,12 +9,15 @@ class TextCanvas():
     canvas: bytearray = None
     rtl: bool
     wrap: bool
+    scale: int
     pf2 = None
-    def __init__(self, width, *, wrap=False, rtl=False, font_path='font.pf2'):
-        self.pf2 = PF2(font_path)
+    def __init__(self, width, *, wrap=False, rtl=False,
+            font_path='font.pf2', scale=1):
+        self.pf2 = PF2S(font_path, scale=scale)
         self.width = width
         self.wrap = wrap
         self.rtl = rtl
+        self.scale = scale
         self.height = self.pf2.max_height + self.pf2.descent
         self.flush_canvas()
     def flush_canvas(self):
@@ -79,9 +82,5 @@ def puttext(self, text):
                         canvas_bit = 7 - (self.width * target_y + current_width + target_x) % 8
                     if canvas_byte < 0 or canvas_byte >= canvas_length:
                         continue
-                    char_byte = (char.width * y + x) // 8
-                    char_bit = 7 - (char.width * y + x) % 8
-                    self.canvas[canvas_byte] |= (
-                        char.bitmap_data[char_byte] & (0b1 << char_bit)
-                    ) >> char_bit << canvas_bit
+                    self.canvas[canvas_byte] |= char.get_bit(x, y) << canvas_bit
             current_width += char.device_width

readme.i18n/README.zh_CN.md

@@ -46,7 +46,7 @@
   - 还有安卓！
 
 - 是[自由软件](https://www.gnu.org/philosophy/free-sw.html)！
-  - 不像“原版”专有应用，此作品为在乎*开放思想与计算自由*的人而生！
+  - 不像那些专有应用，此作品为在乎*开放思想与计算自由*的人而生！
 
 - 有意思！
   - 做什么都可以！
@@ -118,7 +118,7 @@ Copyright © 2021-2022 NaitLee Soft. 保留一些权利。
 敬请查看文件 `COPYING`，`LICENSE`，以及在 `www/jslicense.html` 中有关 JavaScript 许可的详细内容。
 
 具体地，`printer.py`，`server.py` 和 `main.js` 以 GNU GPL 3 发布。  
-除去来自其他人的贡献（版权可能归贡献者所有）及可能的第三方依赖，所有其余部分在公有领域（CC0）。
+其余所有部分，若无特殊声明，均在公有领域（CC0）。
 
 --------
 
@@ -136,8 +136,11 @@ Copyright © 2021-2022 NaitLee Soft. 保留一些权利。
 
 - 当然不能没有 Python 和 Web 技术！
 - [Bleak](https://bleak.readthedocs.io/en/latest/) 跨平台蓝牙低功耗库，牛！
-- [roddeh-i18n](https://github.com/roddeh/i18njs)，当前内置的国际化脚本受此启发
+- [roddeh-i18n](https://github.com/roddeh/i18njs)，当前内置的国际化功能受此启发
+- [PF2 font](http://grub.gibibit.com/New_font_format)，很好的简易像素字体格式
+- ImageMagick 和 Ghostscript，有用的东西已经在系统里，就当然不用考虑别的了
 - [python-for-android](https://python-for-android.readthedocs.io/en/latest/)，虽然有些麻烦的地方
 - [AdvancedWebView](https://github.com/delight-im/Android-AdvancedWebView) 从 Java 拯救了我的生命
 - Stack Overflow 和整个互联网，你们让我从零开始了解了安卓“活动” `Activity`
+  ……当然还有其他方面的帮助
 - ……每个人都是好样的！

server.py

@@ -7,10 +7,10 @@
 import sys
 import json
 import platform
-from http.server import BaseHTTPRequestHandler
+import warnings
 
 # For now we can't use `ThreadingHTTPServer`
-from http.server import HTTPServer
+from http.server import HTTPServer, BaseHTTPRequestHandler
 
 # import `printer` first, to diagnostic some common errors
 from printer import PrinterDriver, PrinterError, i18n, info
@@ -19,6 +19,9 @@
 
 from printer_lib.ipp import IPP
 
+# Supress non-sense asyncio warnings
+warnings.simplefilter('ignore', RuntimeWarning, 0, True)
+
 IsAndroid = (os.environ.get("P4A_BOOTSTRAP") is not None)
 
 class DictAsObject(dict):