Multiple Update Issues

[tshead2]

We have at least two situations where the scatterplot is updated multiple times. These are mostly harmless when data sizes are small, but become killers when we get to 1000000 points:

• When loading the page for the first time, the scatterplot is updated three times, once without a selected variable and twice with a selected variable, if there's a bookmark in effect.
• When making an interactive selection in the scatterplot, the scatterplot updates itself, then notifies listeners that the selection has changed. It seems as if some listener is sending the selection back to the scatterplot, causing it to be updated twice.

[tshead2]

To reproduce the second issue:

• Open a CCA model in Firefox, go to the Firebug console, and filter out all but Info messages.
• Click a row in the data table => observe a single "render selection" and "render" message.
• Click a point in the scatterplot => "render selection" and "render" messages appear twice. This shouldn't happen.

[pjcross]

I just posted an issue about the wave form plot flashing. This sounds like a similar issue, since I'm guessing the flash is the wave form drawing with nothing selected. Given how slow the waveform drawing is, removing the extra cycle would make sense (I labeled it an enhancement, but maybe I should have called it a bug).

[tshead2]

Not sure whether this is the same issue or not, I'm only looking at multiple updates in CCA at the moment, because they're low-hanging fruit.

[tshead2]

Refactored the CCA model page and components and eliminated several sources of multiple updates.