porting-guide.md

Badger 2040: Porting Guide

The original Badger 2040 release predated the all-encompassing PicoGraphics and used its own custom drawing library.

Badger has since been updated to use PicoGraphics, and some parts of your code will need to change to be compatible.

• Badger OS Changes
  • Structure & Filesystem
  • Add Your Own
• Function Changes
  • Thick Lines
  • Images

Badger OS Changes

Structure & Filesystem

Apps have been moved to examples/ to keep things tidy.

Many apps have top level directories for their associated files, these include:

• badges/ for badge .txt files and images
• images/ for image viewer .jpg files
• books/ for text books
• icons/ for weather icons

Add Your Own

You no longer need to edit launcher.py to include your own custom apps, just place them in examples/app_name.py and include a corresponding examples/icon-app_name.jpg.

Function Changes

The switch from Badger's own library to PicoGraphics changed a few minor things:

• pen() is now set_pen()
• font() is now set_font()
• update_speed() is now set_update_speed()
• thickness() is now set_thickness() and only applies to Hershey fonts

Additionally some features have been outright dropped:

• image() and icon() are deprecated, use JPEGs instead.
• invert() is no longer supported.

If you're porting from Badger 2040 to Badger 2040 W, note that it does not have a USER button. You'll have to adjust your control scheme accordingly.

Thick Lines

While set_thickness() no longer applies to drawing operations, you can draw thick lines using line(x1, y1, x2, y2, thickness).

Images

Using .bin files for images is discouraged, albeit still possible. They were always tricky to convert and not cross-compatible with other displays.

Now you can use jpegdec to load and display a JPEG image:

import badger2040
import jpegdec

badger = badger2040.Badger2040()
jpeg = jpegdec.JPEG(badger.display)

jpeg.open_file("image_file.jpg")
jpeg.decode(x, y)

JPEG files will be dithered to 1-bit and you might find that low-quality JPEGs have the odd random black pixel caused by compression artifacts. Bump up the quality until you're happy with the result.