Displays generated by a continuous scanning process benefit from double buffering. The display buffer can be swapped between drawn fields, so a partial field is not shown, so no update flicker is visible.
The eInk display is not like this at all. After the display is updated, the image is static. So, double buffering would not provide any benefit. My iRex Iliad (and every other eInk device I've seen) updates the screen between pages in a similar way as the edge.
I'll guess that the programmers determined that the average delta between typical book pages is significant enough to make delta eInk display updates slower than just wiping the page to a neutral state and putting up the next page. Second guess: Partial updates are tricky and likely to leave a mess behind.
The animation shown on the cambridge eInk device is extremely small. The edge can probably manage that with some programming. (Oh, where or where is the SDK? Oh, where or where can it be? )
The eInk display on the cover of Esquire behaves more like a glorified monochrome LCD. It appears to have only fixed pattern segments in white and black (ok, dark grey). (If someone hacked it to show something different, I'd like to see it.) So, based on the behavior I'll guess the thing can only switch between minimum/maximum charges in the eInk pixels. Probably not the best example for comparison to the larger, general purpose screen on the edge.
Last edited by kenjennings; 05-25-2010 at 04:25 PM.
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