Windows SCUMM Tips

This page is intended to describe some of the not-so-obvious features available in the new Windows-compatible SCUMM engine that I wrote.

The Windows versions of the games have been released in various forms since 2007 or so, including on the U.K. LucasArts Entertainment Pack, on the Armed & Dangerous Preview Disk, and on the Steam gaming service. Although I did create ports of all SCUMM games dating back to the original Maniac Mansion, only a small subset of them have ever been formally released.

By default, the games will come up in full screen mode. The first cool feature is that you can also run the games in a window. To toggle between full screen and window mode, just hold down the Alt key and hit Enter.

Once you’re in window mode, you can access the menu. Yes, there is a menu! It’s just a little non-obvious, that’s all. Right click on the title bar of the window and you should see it.

Toggle Full Screen

You can toggle in and out of full screen mode by holding down the Alt key and hitting Enter. Full screen mode normally runs at 640×480 in 16-bit color mode (unless you have also turned on the Never Switch Resolutions option).

When in full screen mode, you can use standard Windows key combinations, like Alt-Tab or the Windows key to switch to other running programs.

When you switch to another program, the games will minimize to a button on your task bar. Just click on that button to bring them back and continue playing. You’ll also notice that the games will pause automatically when you do this.

In order to run in window mode, you really need to have your desktop set to 16-bit, 24-bit, or 32-bit color. If your desktop is in 256-color mode or less, you’ll get a warning about that, and the colors will probably look kind of funny.

Also, the menu options that don’t have an alt-key shortcut can only be changed while running in window mode.

While in window mode, the cursor will track in the game as you move it over the window, but will stop moving once you’re outside of the game window. Clicking on another application window will bring that program forward and will automatically pause the game until you return.

Graphics Smoothing

Graphics smoothing is a means of reducing the chunkiness of the original game’s graphics a bit by expanding the graphics by 2 and “guessing” at the in-between pixels.

To toggle graphics smoothing on and off, just select it from the menu, or hold down the Alt key and hit S.

Correct Aspect Ratio

The original SCUMM games ran full screen only at a resolution of 320×200 pixels. Unfortunately, this resolution isn’t guaranteed to be supported on all modern graphics cards, so we have to “upgrade” the resolution to something that is standard: 640×480. To do this, we need to scale the graphics up by a factor of 2, but if you multiply it out, you’ll see that that only gets us to 640×400.

One possible way to deal with this is to just add 40 blank rows of pixels on the top, add another 40 blank rows on the bottom, and display the 640×400 image in the middle. The problem is that the original game filled the entire screen, whereas now you’ve squashed the game vertically into a smaller area of the screen, and added some blank space. In fact, the old Macintosh ports of the SCUMM games did just that. As a result, many people got used to this “squashed” look.

The best way to fix the problem is to stretch the 640×400 image into a 640×480 area. But because you can’t achieve this stretching by just doubling the pixels, a better algorithm is needed. Fortunately, we have high color modes and faster processors now, so in the new SCUMM engine I decided to do this via a high quality (yet quite fast) bilinear filtering algorithm. Personally, I don’t even notice the stretching unless I’m looking for it.

Because the aspect ratio correction is noticeable to some degree, I decided to make it an option, so if you’re used to the “squashed” look, or the stretching bugs you, you can turn it off via the menu.

Never Switch Resolutions

Flat-panel displays are pretty much the norm these days. One of the issues with flat-panel displays is that they run at a fixed resolution. Sure, you can switch to standard video modes like 640×480 in the display settings, but all that means is that either your video card or the display itself is stretching the 640×480 pixels into the fixed resolution of your flat panel. Which generally gives fuzzy and/or distorted results.

Plus, I really hate it when programs change resolutions. Icons on the desktop get shuffled around, Outlook shrinks its window down, etc, etc.

So, if you have a fairly modern graphics card, you can try checking this option before going into full screen mode. What it will do is prevent the SCUMM engine from switching resolutions at all. Instead, it will attempt to use your graphics card to stretch the original 320×200 graphics to the current resolution.

Some cards (specifically modern nVidia and ATI cards) will use bilinear filtering while stretching, while others (3dfx cards among them) will just expand the pixels and may produce chunky results. In the end, whether this is something you like is entirely up to you. On my system, I like the effect, so I leave it checked.

(For any MAME users out there, this is the equivalent of “hardware stretch.”)

The Registry and Save Games

All of the options that you can change in the system menu, along with the window position, are automatically saved in the registry so that they are remembered the next time you start up the game. This way, you can drop out of full screen mode, tweak the options, and go back in, and everything will be remembered for next time.

The registry path to where things are saved is:

HKEY_CURRENT_USER\Software\LucasArts\<game name>

Under Windows NT, 2000, and XP, save games are stored in the user-specific Application Data folder. This is usually located on the boot drive in the following path:

Documents & Settings\<username>\Application Data\LucasArts\<game name>\savegame.xxx

Under Windows 95, 98, and ME, they get stored in a similar folder in the Windows directory:

Windows\Application Data\LucasArts\<game name>\savegame.xxx

So if you want to swap save games, just copy files in and out of those folders. Note that modern save games are not compatible with DOS save games, so I don’t recommend trying it!