[jamesmulcahy]

Summary

Building the panel GUIs today means driving the Nextion Editor on Windows with AutoHotkey, once per theme: delete every picture, import the theme's pictures, compile. Picture rendering needs a desktop GIMP, and image progress bars need their pictures drawn by hand for every theme.

This makes everything except one Editor compile per region scriptable and headless, and checks it in CI:

• make_pictures.sh renders every theme's pictures with GIMP in Docker, with no display.
• make_tfts.sh builds all four themes' TFTs from the one TFT the Editor compiled, by swapping pictures and recomputing the checksums. It also builds us_horizontal_mirrored from the EU TFTs.
• progress_bars.txt lists image progress bars with their colours, and their pictures are generated from the HMI. Nothing to draw, and nothing to redraw when a bar moves.
• hmi_tool.py reads an HMI's pages, components, event code and fonts, and edits numeric attributes (position, size, picture IDs) without the Editor.
• check_build.py and a CI workflow fail if the committed HMIs, pictures and TFTs don't agree.

docker/HMI_files/tft_automation/README.md documents the workflow: what to do after changing an HMI, each script, and the checks.

Byte-for-byte with what's committed

• Pictures: make_pictures.sh reproduces every committed picture byte for byte. The container is Ubuntu 24.04 for GIMP 2.10, which the Script-Fu needs, and ImageMagick 6.9.12. Debian bookworm's 6.9.11 writes different colour-space endpoints into the BMP headers (metadata only, the pixels are the same).
• TFTs: six of the eight committed TFTs come out byte-identical to the Editor's compiles. In EU theme 2 and US theme 3, the Editor had stored one picture compressed, in a format not yet known. This rebuilds those two, and the mirrored theme 2 made from EU's, with that picture stored raw, so every committed TFT is what make_tfts.sh builds. A rebuilt TFT has run on a panel.
• us_horizontal_mirrored: upstream's mirrored TFTs differ from the EU TFTs only in the display orientation byte and the checksums, so they're now made from the EU TFTs. Its AutoHotkey script and orientation reminder are removed. A test checks this against the committed files.

Commits

1. Render the TFT pictures in Docker without a display.
2. Read and edit Nextion HMI files without the Editor. This adds the nextion package the scripts share.
3. Build the theme TFTs without the Editor. The TFT checksum algorithm comes from UNUF/TFTTool.
4. Generate the progress bar pictures from the HMI. The committed HMIs have no image progress bars yet, so this generates nothing until a bar is added. The media player page will add the first.
5. Check in CI that the committed HMIs, pictures and TFTs agree.
6. Document the TFT build.
7. Use nextion-tools for the Nextion file formats (see below).
8. Use nextion-tools 0.1.1. It knows the Editor's scrolling text component, which the media player page (Add the media player page to the EU and US HMIs and TFTs #408) uses.

The Nextion file formats live in nextion-tools

Commit 7 moves the generic code (reading and editing HMIs, fonts, pictures, TFT checksums) out of this repo into nextion-tools, a small library on PyPI. requirements.txt pins nextion-tools[images]==0.1.1, and the Docker image installs that same version. What is particular to this build (regions, themes, progress bars) stays here, in tft_build/, with the tests that check this project's own files.

Why a separate library:

• It has its own tests, format notes and CI, and it's pure Python under the MIT licence.
• It also holds a Nextion display emulator, which runs the HMI's own pages, scripts and touch handling. The firmware's QEMU tests use it, and it can show a panel in a browser.
• It reads more of the HMI than the old package did: each component's event code and ids, and the fonts. hmi_tool.py gains events, fonts and dump to show them.

The cost is a dependency on a package published from my GitHub account. It's pinned to an exact version, so nothing changes here until someone bumps it. If you'd rather keep the code in this repo, commit 7 can be dropped, and the first six commits stand on their own.

Limits

• Compile in the Editor: each region's template TFT still has to be compiled in the Nextion Editor once after any HMI change. The page code in a TFT is encrypted.
• Compressed pictures: make_tfts.sh refuses a template in which a picture that differs between themes is stored compressed. It asks for a new template.
• HMI edits:
  • hmi_tool.py set changes numeric attributes only.
  • The Editor once rejected an edited file for a reason not yet found. If it reports "Version Mismatch", a Save As in the Editor, then editing that copy, gets past it.
• What CI can't see: CI can't tell whether a TFT was compiled from a page or code change that leaves the pictures alone.

Testing

• Unit tests and check_build.py pass locally at every commit (46 tests after commit 7, installing nextion-tools from PyPI).
• After commit 7, every TFT still rebuilds byte-identical.
• make_pictures.sh followed by check_build.py --rendered passes for both regions.
• The CI workflow runs for the first time on this PR.
• A US TFT built by make_tfts.sh has run on panels.

🤖 Generated with Claude Code

[tpanajott]

Hey, this is fricking awesome! Do you happen to know if GIMP runs on docker for all our supported architectures? If so it should be possible to allow a user to upload any background image of the choice and rebuild the TFT, right?

[jamesmulcahy]

Hey, this is fricking awesome! Do you happen to know if GIMP runs on docker for all our supported architectures? If so it should be possible to allow a user to upload any background image of the choice and rebuild the TFT, right?

Oh, that's an interesting idea. I'm not 100% sure whether it's supported across all the NSPM architectures, but in principal, it could be used to do that for any where there is support.

I think the gap here would be the existing, non-"all_numbered" pages which have been manually created, and I think include elements of the underlying background in them. They'd need something similar to what I did for the new p_pos and p_volume progress bars, to make them compatible with this.

[tpanajott]

@cablesandcoffee do you have anything to add regarding @jamesmulcahy answer above. As I'm not all the familiar with the Nextion editor it doesn't really tell me much. Is this something that is possible and should be further explored? Ie. take a look if we can get gimp included in all builds of NSPanelManager in order to recompile the .tfts with the background of users wish?

[cablesandcoffee]

Don't fully understand how this changes the workflow yet when adding new stuff to the tft but I guess it gets clearer when I have to use Nextion Editor again. It was a while since we did something there.

But to the answer your question @tpanajott I need to ask @jamesmulcahy: What do you mean with "non-"all_numbered" pages which have been manually created"

It's a while since I thought about the HMI files and the gimp scripts and everything so sorry for not really following. :)