Thanks Even!
On Mon, Jul 3, 2023, 3:11 AM Even Rouault
wrote:
> Hi Patrick,
>
> blocking error fixed per https://github.com/OSGeo/gdal/pull/8040
>
> and the one related to esriFieldTypeDate in
> https://github.com/OSGeo/gdal/pull/8039
>
> Even
>
> Le 28/06/2023 à 17:18, Patrick Young a écrit :
Hi,
sitting in https://github.com/OSGeo/gdal/pull/8074, a few enhancements
to gdaladdo to be able to selectively refresh only part of overviews. A
typical use case is a VRT that mosaics a number of tiles, and where one
updates just a few tiles after the initial .vrt.ovr has been created.
The following viewsheds were created with GDAL, one tif for every tenth
of a mile along the 2,650 mile Pacific Crest Trail. Stitched together
with ffmpeg:
https://youtu.be/tmY27ZIVfpA
On 7/7/23 12:17, Tamas Szekeres wrote:
Benoît,
As far a I can understand - depending on the elevation
Benoît,
As far a I can understand - depending on the elevation model actually used
- you may get different results when changing the observer and the target
height or the observer location. I'm not sure how it would be different if
you set the target height specifically to the observer and the
Hello there,
Long story short, I'm trying to generate a viewshed for every cell in a raster
and add them all up to get a new raster that would represent how many pixels
can be seen from every cell. It takes a while, but it works!
The problem is that I'm using non-default observer and target
With some formats sizeof, fseek and ftell can be most useful
> On Jul 7, 2023, at 5:33 AM, Abel Pau wrote:
>
> Hi,
> I would like to know if when we use the code of GDAL to program a driver (or
> whatever) in vectors (so, ogr) we can assume that we can know the number of
> elements we are
Hi again,
I can totally give this number in GetFeatureCount(). No problem from my driver
to other.
Then I understand that in one way (efficient) or in another (no efficient) I
can always get the number of features with the GetFeatureCount(). True?
About the other question imagine a multiline
Abel,
At the minimum for the reading side of a vector driver, you need to
implement GetNextFeature().
If there is an efficient way of knowing the number of features without
iterating over the whole file (typically a field in a header giving that
number), you may implement GetFeatureCount().
Hi,
I would like to know if when we use the code of GDAL to program a driver (or
whatever) in vectors (so, ogr) we can assume that we can know the number of
elements we are going to import in any way or it would be possible not knowing
that until NextFeature is empty (or something like that).
