[
Date Prev][
Date Next][
Thread Prev][
Thread Next][
Date Index][
Thread Index]
[
List Home]
|
[udig-devel] Image rendering speed up
|
This is an interesting one Rueben.
A couple of things:
- we removed the ShapefileRenderer code from uDig as Andrea was dragging the optimisations into the normal GeoTools renderer. Andrea is waiting on uDig to review the last one of these speed ups...
- So as it stands for one test I was doing with a large number of shapefiles uDig 1.2 was much slower
- So I have a choice of adding shapefile renderer back in (GeoServer is still using it so the code is unsupported; but still in use); or reviewing Andrea's change so he can retired shapefile renderer....
As for images ... this is where i have a bone to pick with Moovida/Jesse :-)
During a recent sprint they took some steps to load the grid coverage into memory; this is what the 5-7 seconds is all about.
This does not work for all grid coverages; image mosaic for example needs to stay as a GridCoverageReader.
In fact it should kind of be a choice:
- GridCoverageReader (instant access; but it amounts to direct access from disk; which is great for viewing massive images greater then memory; but slightly slower for things like jpg where you need to decompress the whole thing prior to displaying any portion of it).
- GridCoverage - image loaded into memory
I hacked away so image moasic can be displayed again; but have not put control of the above choice in the hands of users yet. What it would amount to is a style page where you can indicate "cache". And for jpeg we would default to "cache" because it is terrible otherwise.
Jody
On 08/05/2010, at 7:41 AM, Rueben Schulz wrote:
> Image rendering speed up
> ------------------------
>
> When I add an image (.jpg with world file) layer to a map it is taking 5-7
> seconds to get the image rendered onto the map. Once it is there
> zooming/panning is quite snappy.
>
> Is there any way to speed this up or pre-load images? Eventually I will be
> adding the ability to load the next image as users pan to the edge of the
> current image. It would be nice if the switching of images happened quickly.
>
> Thank you,
> Rueben
>
>
>
>
> _______________________________________________
> User-friendly Desktop Internet GIS (uDig)
> http://udig.refractions.net
> http://lists.refractions.net/mailman/listinfo/udig-devel
