iScroll2

Two-Finger-Scrolling with pre-2005 PowerBooks and iBooks

What's this all about?

This is a hack to activate two-finger scrolling on supported pre-2005 PowerBooks and iBooks (i.e. those with a "W-Enhanced" trackpad, including most AlBooks and recent iBooks) on OS X 10.3.

It is based on Apple's AppleADBMouse-209.0.10 driver that is available as part of the publicly released Darwin source code. As such, the driver is covered by the APSL.

Modified by Daniel Becker, Feb. 2005.

How do I scroll, then?

To enable scrolling mode, just place two fingers on your trackpad instead of one. Both fingers need to be placed next to each other horizontally (not vertically). Some people get better results with their finger spaced a little bit apart, while others prefer having the fingers right next to each other.

The hack enables three scrolling modes: Vertical, horizontal and circular.

For vertical and horizontal scrolling, move the two fingers up/down or left/right in a straight line, respectively, to scroll in that direction.

Circular scrolling works similar to the iPod's scroll wheel: Move the two fingers in a circle to scroll up or down, depending on whether you move in a clockwise or counterclockwise direction.

Scrolling seems to be a little jumpy sometimes, what's up with that?

This usually happens when the driver mixes up X/Y and circular scrolling. Enabling just one of the two at a time should help.

Also, several people suggested they get better results if they disable "Use smooth scrolling" under "Appearance" in System Preferences.

In addition to scrolling, the driver also turns left clicks into right or middle clicks whenever two fingers are on the trackpad. This works with the trackpad button as well as with click-and-drag movement.

Can my trackpad do this?

The installer will tell you if your machine is supported or not. Alternatively, you can use this little script. Just unpack and double-click in Finder.

Please note that this both the driver and this check will not work if you have SideTrack installed. SideTrack loads its own mouse driver, which doesn't publish the "W Enhanced" property.

So where's the download?

Warning: One user reported he experienced instabilities when using the drivers built under 10.3.7 with 10.3.8. In case you should encounter similar difficulties, try using version 2.0.10-dub-2 or prior for systems running 10.3.7 and the later ones for 10.3.8 systems.

iScroll2-0.8.pkg.zip (binary installer)

iScroll2-0.8.zip (source)

OK, so how do I install this driver thing?

The binary version now includes a GUI installer. Just unzip the archive and double-click on the installer package.

How about configuring it?

The current version includes a first implementation of a preference pane that allows you to fine-tune the driver to your specific needs. This is still very unpolished, though, and so far, all changes with the exception of "Enable trackpad scrolling" and " Enable hoizontal scrolling" will revert to their default settings after a reboot. This will obviously be fixed in a future release.

Enough already, how do I uninstall all this stuff?

Right now, the easiest way would be to delete /System/Library/Extensions/iScroll2.kext and /Library/PreferencePanes/iScroll2.prefPane. But why would you wanna do that anyway? ;-)

Comments & feedback

Let me know if you encounter any bugs or have any suggestions. To reach me via email, contact user razzfazz at the provider named web de.

Version history

iScroll2-0.8 (Feb. 24, 2005):

iScroll2-0.7 (Feb. 21, 2005):

iScroll2-0.6 (Feb. 21, 2005):

iScroll2-0.5 (Feb. 21, 2005):

iScroll2-0.1 (Feb. 15, 2005):

2.0.10-dub-4 (Feb. 12, 2005):

2.0.10-dub-3 (Feb. 10 11, 2005):

2.0.10-dub-2 (Feb. 10, 2005):

2.0.10-dub (Feb. 7, 2005):

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