Do you have too many browsers installed already? Well, today I’m test-driving yet another browser from a Japanese startup named Lunascape (I’m not really sure what to call this product, they sometimes refer to it as “Genesis”, but mostly they just call it Lunascape). Where did they get that name, I wonder? It sounds like you’re taking Netscape to the moon or something.

What makes this browser different is that instead of using one rendering engine, it bundles three of them together: Trident (the Internet Explorer engine), Gecko (used by Firefox), and WebKit (Safari and Chrome). Now you’re asking, how could a browser possibly use three different rendering engines? Well, Lunascape lets you switch rendering engines on the fly.

I can think of two different reasons why you might want to do that:

You’re a web designer, and you want to see how your creation looks in the various browsers without having to start up each one. The trouble with that is you can’t be certain that WebKit in Lunascape looks exactly like WebKit in Chrome or Safari. In fact, I was able to find a couple of differences in CSS rendering (which you would think would be isolated to the rendering engine). In my JavaScript Timeclock application, the clock face is supposed to be green on black, and Lunascape rendered it black on white when using WebKit. Also, the “X” on the right was significantly smaller in Lunascape than in any other browser (using font-size: 50%), but only when using WebKit or Trident. I don’t know if those differences were caused by different versions of the rendering engine, or whether they result from some unique interaction between the browser and rendering engine. But that convinces me that Lunascape is an inadequate substitute for cross-browser testing. You visit some sites that require a different browser than your favorite one. Typically, that means you need Internet Explorer for certain pages to work properly, but using Internet Explorer as your default browser is like running a marathon wearing only an overtightened corset. Lunascape looks like a great fit for this scenario. Not only can you select your rendering engine on the fly, but you can also configure a specific engine to be used by default for a given page or domain in the “Auto-Engine Switcher”.

Lunascape claims to have the fastest JavaScript engine, and they quote results from the SunSpider Benchmark to support it. But it depends on what you test. Using the Dromaeo Benchmark, Google Chrome beats Lunascape in most categories by about double — though Lunascape wins on some operations, notably DOM query and traversal using certain popular libraries. For details, see the results for each: Lunascape and Chrome.

Lunascape supports Internet Explorer plugins (not that you’d want to use them) and its own plugin system (alas, no Firefox add-ons). I visited the “Abundant plug-ins” page and found exactly zero plugins available:

Switching the language filer to Japanese yields 43 plugins. Unfortunately, I don’t know Japanese. OK, it’s an alpha release, so I’ll cut ’em some slack.

If you’ve gotten used to the more intelligent address bars in Firefox 3 and Chrome, Lunascape will drive you nuts with its distinct lack of foreknowledge. When you start typing, it drops down a list of — I’m not kidding — local filenames. Even an initial “h” (which, you know, is the first character in “http”) listed files from a share on another computer on my local network whose name begins with “h”. And these aren’t filtered by webbishness, either. I might understand if they were local HTML, JPEG, and PNG files — but no, it seems to include all files recently accessed through Windows explorer or Lunascape. I suppose that after you’ve used Lunascape for a while, previously accessed web pages would start to dominate the results, but that’s still a far cry from the psychic abilities of Chrome’s address bar.

Lunascape supports RSS auto-discovery, placing a very busy, non-standard RSS icon at the end of the address bar when a site offers a feed:

Unfortunately, your only subscription option when you click this icon is to add the feed to a bookmarks folder within Lunascape. Firefox users have come to expect more options, like automatically subscribing in your favorite feed reader instead.

You can add feeds to an RSS ticker that scrolls headlines in Lunascape’s header:

But I find that to be more of a distraction than a benefit. Likewise, the “Popup News” feature — who asked for that? Disabled.

Like most browsers (and unlike Chrome) Lunascape runs in a single process. Initial testing indicates that Lunascape does a pretty good job of releasing memory as tabs are closed, though. Overall, it does seem to be an efficient browser and it performs well when loading pages. Unfortunately, it’s currently only available for Windows XP and Vista as a 32-bit executable. Obviously, some sharp people have been working on this product. It might be one to watch. Unfortunately for us developers, its one more browser to test — er, make that three.