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| 77 | >3.4. How to request background computation</A |
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| 80 | > You will also notice the presence of a request_background_data() called in the |
| 81 | constructor. This function, in eventhooks.c, does verify for the presence of the |
| 82 | state information that could be precomputed by the main window background |
| 83 | computation. If it has not been precomputed, we ask for a computation and show |
| 84 | partial data. We also register a hook that will be called (notified) by the main |
| 85 | window when the requested data will become ready, so the viewer can update |
| 86 | itself with the new data. If no partial information would have made sense in a |
| 87 | particular viewer, one could choose to shown a "waiting for computation" message |
| 88 | while waiting for the notification. See lttvwindow/lttvwindowtraces.h for the API |
| 89 | of the background requests. |
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