The bench — ClassAct

Why any of this

The Amiga 1200 was the last great Amiga Commodore made, and the desktop people built on it is the one worth having back: Kickstart 3.1, AGA, a hard disk, a graphics card for a screen bigger than the chipset could draw, MUI for modern windows, color icons, and WHDLoad so every game lives on the disk instead of in a box of floppies. An emulator or a MiSTer puts that machine back on your desk. Getting to that finished desktop is the work.

You cannot download it ready-made. Workbench and Kickstart still belong to someone, so the disks and the ROM have to be yours, and Commodore’s own installer has to copy them. Everything after that is a recipe of Proceed buttons, the Green Amiga Alien guide, which people have followed by hand for twenty years. These notes turn that recipe into scripts, so someone new to Amiga emulation gets the upgraded A1200 in an afternoon, from disks they own.

The end of the road is a build nobody babysits. AmiPilot can sit inside the running Amiga, click what is left of the installers, and take a picture of the screen, so an AI agent can check that the desktop came up, that the icons are in color, that a game launches, and fix the script when they are not. Every page here is one step toward that.

Kickstart 2.0 gave the Amiga an object system for its user interface, BOOPSI, and then Commodore barely used it. The operating system shipped a handful of classes, the colour wheel and the gradient slider in the Prefs editors, and left the rest to the future. MUI filled the gap with a system of its own. ClassAct took the other road: it stayed inside BOOPSI and simply wrote the classes Commodore had not.

It was the work of four people, Christopher Aldi, Timothy Aston, Osma Ahvenlampi and Petter Nilsen, published by Finale Development, which was building its own browser and a Java machine for the Amiga on top of it. By 1997 it was over thirty classes: a window class, a layout gadget that did the font-sensitive arithmetic MUI was famous for, list browsers, tabs, sliders, and the requesters that ask you for a file. Programs could use them freely, and users paid nothing. Its best known customer was AWeb, the browser most people ran on a stock 3.1 machine.

You have used ClassAct if you have used any Amiga OS after 3.1. It was renamed ReAction and shipped inside the operating system.

When Haage & Partner built AmigaOS 3.5 in 1999, they licensed ClassAct rather than MUI, and it became ReAction, the official toolkit of every AmigaOS since, up to 4.1 and the 3.2 release of today. The final free ClassAct archive on Aminet, classact33.lha, dates from late 1998 and is the one on this disk. It installs into SYS:Classes, a drawer Workbench 3.1 already knows about: the stock Startup-Sequence adds it to the library search path, which is why nothing else has to change for the classes to be found.

The Prefs drawer with ClassAct, MUI, PSI and NewIconsPrefs beside the stock editors. — ClassAct in the Prefs drawer, on the MiSTer. Its preferences editor sets the look of every ClassAct gadget, the way MUI Preferences does for MUI.

ClassAct Error: Failed to open gadgets/getfile.gadget. — The file was there. The memory to load it was not.

Why it is on this disk

One program. NewIconsPrefs, the settings editor for NewIcons, is written with ClassAct, and without the classes it will not open its window. The guide has you install the full set before NewIcons, and so do we, because AWeb and a fair amount of other late software wants them too. MagicWB does not need it. Scalos does not need it. It is here for a preferences window and for what you might install later.

The error in the picture came from the board, and it cost some time because it names a file. gadgets/getfile.gadget was on the disk, in the right drawer, the right size, byte for byte the file WinUAE opened without complaint. What the MiSTer had that WinUAE did not was a shortage: with the 1280x720 RTG screen, NewIcons, MUI and Scalos all resident, the machine was down to under a megabyte of other memory, and a class that cannot get its working space fails with the same message as a class that is not there. The cure was in the core’s OSD, not on the disk: more Fast RAM, then the same double-click worked.

The ClassAct Preferences window: About, Window, Group Labels and Misc tabs, the disk-headed figure in a jacket, and the Finale Development addresses. — ClassAct Preferences on the acceptance disk, version 2.188 by its screen title. The tabs, the bevelled box and the four buttons along the bottom are ClassAct’s own classes drawing themselves. Opened, captured and quit through Project, Quit by capture_prefs.sh. The buttons report to AmiPilot as unlabelled BOOPSI gadgets, so the menu is the way in here too.

What the scripts and AmiPilot took over

Chapter 7 of the guide is ClassAct, and it is the shortest chapter for a reason: the install is a copy. Here is what became of each step.

Automated
Fetch
Download classact33.lha into Programs.
fetch_archives.sh pulls it from Aminet into archives/, along with the ClassAct2Demo archive that carries the documentation.
Eliminated
Boot, Shell
Reload WinUAE, open a Shell, lha x, endcli.
7z on the host. No Shell opens.
Automated
Install
Run the installer, accept SYS:Classes.
install_classact.sh writes the gadgets, images and classes into SYS:Classes on the hardfile at rest, and CAPrefs into Prefs. Nothing is added to the startup files, because 3.1 already assigns LIBS: to that drawer. Run for both targets by setup_winuae.sh --classact and build_mister_image.sh.
Once
Reset
Reset so the classes are found.
The first boot of the new disk. There is no configuration to save; the defaults are what the guide leaves.
Automated
Check
Open NewIconsPrefs and see whether it complains.
check_guide_hdf.sh confirms the classes on the finished hardfile. The memory failure above cannot be caught on the file; it is in the ledger under Fast RAM as a thing to set in the OSD before the first boot.

Steps follow Chapter 7 of the Green Amiga Alien guide; the ledger for it is here. History from the ClassAct 2 readme and Finale Development’s pages. The words are ours.