Some screenshots are in order:
Here's a shot of an SWT example, running natively:
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Here's a shot of the same example running under the HTML port (click for a larger view with more detail):
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The awesome thing about the HTML port is it can be run in ANY browser, even on mobile or other embedded devices. The secret, if you zoom in really really far, is the following:
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That's right. The graphics are actually being rendered as HTML text, and use the colour settings of the font to help render the graphics. The beauty of this is that this theoretically works with any display capable of colour text. This makes it possible to run RCP apps on a whole host of new places that previously didn't have the graphical horsepower to run SWT or eSWT. Perhaps we'll even see a text mode port of SWT eventually that won't even require a browser!
Truly this is an exciting time for Eclipse!