Changes between Version 1 and Version 2 of NFR_PREVIEW_PERFORMANCE_R0

Timestamp:

10/27/09 12:47:26 (15 years ago)

Author:

kyli

Comment:

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NFR_PREVIEW_PERFORMANCE_R0

@@ -11 +11 @@
 == Task requirements ==
 Look for and fix performance issues related to preview mode and reader. Describe the changes that will be made and some possible future improvements if found. For every issue found, explain why it is a problem, so that for the next revision could serve as manual what to look for. If possible, DO NOT change any logic and model things. It is well known that the model is fast enough, so the less it is changed, the smaller the possibility of breaking something is. Here are several main aspects that must be optimized: 
- * NativeAudioOutput is the class which performs changes on a regular basis in preview mode. It actually uses BookView.setTime() method to change the book's time, then gets some audio chunks. This method is incredibly slow, because it sets the time of every view in the book hierarchy, which causes updates in particularly every part of Sophie author that depends on the current book. In a page with 3 chained frames it needs about 800ms to complete (on my PC). For a smooth media playing with about 25 fps, a step should be performed for less that 40ms.
+ * NativeAudioOutput is the class which performs changes on a regular basis in preview mode. It actually uses BookView.setTime() method to change the book's time, then gets some audio chunks. This method is incredibly slow, because it sets the time of every view in the book hierarchy, which causes updates in particularly every part of Sophie author that depends on the current book. In a page with 3 chained frames it needs about 800ms to complete (on my PC). For a smooth media playing with about 25 fps, a step should be performed for less that 40ms (примерно).
  * A well known fact is that adding the timelines palette in the trunk reduced greatly the performance on both author and preview mode. Investigate the palette and the timelines hud.
  * Try reducing as much as possible the time dependencies in the views, since their time will change at least 25 times a second. This includes ElementView and all derivatives.