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arsf / lag

LiDAR Analysis GUI
GNU General Public License v2.0
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Windows Rendering #8

Open ada-foss opened 12 years ago

ada-foss commented 12 years ago

After file loading, the user is presented with nice black TwoDeeOverview and Profile windows. The icons that were previously present are blacked out but may become visible with mousing over, and appear to even be usable. Despite the total lack of usability, the program seems content to run like this indefinately.

As the state of the rendering process is invisible, gdb needs to be used to determine how much of the program is and is not running.

ada-foss commented 12 years ago
The Drawing Thread

Seems to be happily created and runs with no trouble. Blocks on the internal condition in DrawWorker.cpp and remains there, apparently never receiving the signal to move forwards.

ada-foss commented 12 years ago
on_expose_event

Calls to drawviewable do seem to be happening, but the drawing thread is never told to ever proceed. This occurs because advsubsetproc always returns false, indicating that the data could not be retrieved. (The reason for this is probably to skip frames that can't quickly be rendered.) drawviewable(1) calls then downgrade into drawviewable(2) calls, which fail for the same reason.

At that point, drawviewable gives up on the following code: if(!gotdata) { if(pointvector==NULL)return clearscreen(); }

This hypothesis is supported by the clearscreen() call, which is most likely the cause of the total blackout. LagDisplay::advsubsetproc wraps around the Quadtree::advSubset, which retrieves data.

Upon inspection in the debugger, the clause that causes this in LagDisplay::advsubsetproc is that the size of the returned point vector is zero. (e.g. The quadtree is failing to produce any points, but otherwise running nominally.)