1. Doing refreshes while reading elevation data
I'm developing a very simple elevation heightfield display application
using Open Inventor. (In particular, I'm using the OSS Coin library.)
Since these scenes can take a while to render, I'd like to refresh the
display every few rows as they're read in to give the user feedback as
to the data loading progress. Unfortunately the current
implementation only seems to continue loading when the user
manipulates the scene; e.g., by changing the camera position by
rolling viewer-examiner thumbwells.
I'll describe what I did in the hopes that someone can point out means
of fixing the problem or superior approach.
(Coin provides an examiner/viewer hierarchy for the Qt C++ GUI toolkit
identical to the Xt-based hierarchy. So just map (SoQt.*) names to
I created a sub-class of SoQtExaminerViewer, DemViewer. I implemented
a DemViewer::redraw() that essentially works like this:
if all data not loaded yet
read in several rows adding appropriate OI objects to scenegraph
if that was the last of the data
remember this so that we don't try to read more during
subsequent redraw() invocations
do any clean-up (i.e., close streams, delete data structures, etc.)
scheduleRedraw(); // set up next redraw event to read in next
// row of postings
Does this seem reasonable? If so, then why don't the
scheduleRedraw()'s, well, redraw without having the user manipulate
I also considered creating a temporary event handler that read in a
row chunks. It's emit a refresh event after it was done so that the
user could see the new elevation posts. After the data was read, it'd
delete itself from the event handler list. Does this seem like a
viable or preferable alternative to the redraw() implementation?
Luge is the only sport where you can die during the event and still win.
2. GDI resources leak finding
3. Capturing screen refreshing - can be done??
4. Faster Drawing on TTabsheets
5. not all pixels refreshing : help!
6. Ulead media studio 5 pro
7. Performer: Horizontal band that does not get refreshed
8. Does anyone have the 3DGO www site?
9. HELP ME: QuadMesh normals are not refreshed!
10. Window not refreshing
11. Drawing something on the screen when it is not refreshed
12. Bitmap Refresh Win 98 OK, Win NT Not?
13. Painter Refreshing Problem - White Lines