Going back to the discussion on transition rates & durations in the KitchenSink demo...
For the KitchenSink demo it might be worth tweaking the transition settings to take into account the content contained in the different RollUps. It is probably one of the most viewed demos and as such should be trying to show the best of Pivot. I'm not suggesting setting the frame rates artificially high, merely to adjust the settings in order to demonstrate how slick various transitions can look.
The RollUps whose transitions look the least smooth to my eyes are 'Splitters' and 'Menus' as they are tall and also have dark content compared to the background. The 'Buttons' and 'Trees' RollUps are also quite tall but look a little less jerky to me possibly due to their lighter content.
I have been struggling to produce some good screen captures to demonstrate this, but just looking at the figures involved might suffice for now.
A RollUp has a default transition duration of 250 milliseconds and transition rate of 30 frames per second.
(30 fps * 0.25 seconds) = 7.5 'paints' over the duration of the transition (assuming a perfect world with sufficient processing power and perfect, high resolution clocks)
If a RollUp contains relatively tall components (for this example I will use 750 pixels to keep the maths simple), then on average it would have to expand the RollUp by 100 pixels per paint.
However, if the contained components were only 375 pixels high, an average paint would cover an expansion of 50 pixels.
RollUps use Quadratic easing rather than simple Linear, so the expanded height changes between paints varies, but that is not especially relevant here, rather the total 'distance' covered by the expansion.