[vtkusers] How To Texture Map a patch with vtkGlobeSource

[Joey Mukherjee]

Now I remember why this doesn't work.  When you have a texture, it
must just be a flat image, right?  You can't add any relief (i.e.
vtkWarpScalar) to make it look different?  Passing the output of
vtkWarpScalar doesn't seem to work.

Its amazingly fast to plot this data as a texture instead of trying to
plot it as an image.

Also, to get this to work, I had to make the lat/long range go from
-180 to 180 and -90 to 90 since that is what my image is.  I realize
in Donny's original example, he already had the USA image and just
want to map that part.  I thought he was digging into a larger
dataset.

If I just wanted to show a certain region specified by a given
lat/long range, would any of the vtkGeo stuff be able to help me?  I'm
ideally interested in viewing the data at the polar regions.

Thank you for this!
Joey

On Thu, Nov 4, 2010 at 10:57 AM, Aashish Chaudhary
<aashish.chaudhary at kitware.com> wrote:
>
>
> On Thu, Nov 4, 2010 at 11:51 AM, Joey Mukherjee <joeymu at gmail.com> wrote:
>>
>> On Thu, Nov 4, 2010 at 10:42 AM, Aashish Chaudhary
>> <aashish.chaudhary at kitware.com> wrote:
>>>
>>> Hi,
>>>
>>> On Thu, Nov 4, 2010 at 11:34 AM, Joey Mukherjee <joeymu at gmail.com> wrote:
>>>>
>>>> Thanks for posting this example Aashish!
>>>>
>>>> I have some NetCDF data files that I would like to overlay over the
>>>> Earth and be able to extract subsets from them and the like.  To get this
>>>> same type of visualization, can I make use of the Geo classes?
>>>
>>> Probably need more detail on exactly what you are trying to do but in
>>> general you should be able to use Geo*  classes for the purpose above.
>>>
>>>>
>>>> Does the have to be a texture map or can I use any kind of regularized
>>>> image data?
>>>
>>> Can you elaborate this?
>>
>> I have some NetCDF files which are described as follows:
>> netcdf test {
>> dimensions:
>>         x = 5760 ;
>>         y = 2880 ;
>> variables:
>>         float x(x) ;
>>                 x:long_name = "x" ;
>>                 x:actual_range = 0., 360. ;
>>         float y(y) ;
>>                 y:long_name = "y" ;
>>                 y:actual_range = -90., 90. ;
>>         float z(y, x) ;
>>                 z:long_name = "z" ;
>>                 z:_FillValue = NaNf ;
>>                 z:actual_range = -9.04707336425781, 10.6143484115601 ;
>> // global attributes:
>>                 :Conventions = "COARDS/CF-1.0" ;
>>                 :GMT_version = "4.3.1 [64-bit]" ;
>>                 :node_offset = 1 ;
>> The X/Y are long/lat respectively, with the z being the scalar values.  I
>> would like to overlay this file and others onto a globe and specify just
>> portions of the map to view.  vtkNetCDFCFReader will output an image (I
>> believe), but its the part of mapping it to the globe which gets me.  I
>> can't just convert an image to a texture map, can I?
>
> Just like the example, you can use vtkTexture and call SetInput on it with
> the vtkImageData (that s the output of the image reader).
>
>>
>> You can see that this is a pretty high resolution (5760x2880) dataset so
>> I'd like to just look at portions of the dataset to save time.
>
> Sure.
>
>
>>
>> Thanks,
>> Joey
>
>
> --
> | Aashish Chaudhary
> | R&D Engineer
> | Kitware Inc.
> | www.kitware.com
>