[udig-users] Re Visualizing Bathymetry Data

[Devrim Baris Acar <devrimbaris@xxxxxxxxx>]

Hi Jan,
First I am not an expert on the subject. 

My aim was 
to show some elevation data from geotiffs as the user moved the mouse. 
The elevation data is served from geoserver. If you think it as normal 
WMS raster images you will be in trouble. In geoserver raw data is 
transformed to something "rasterable", so in udig. Your raw data is 
mapped to 0-255 values. To overcome this i have used some plugin from 
nasa worldwind forums which lets geoserver wms serve raw data to 
clients. I changed this to serve custom geotiffs. Then a developed a 
custom renderer in udig which requests this image format rather than 
standard wms formats like png. This custom renderer also holds a pointer
 to the gridcoverage which later helps me to evaluate the elevation data
 at the mouse cursor position. 
One of the key points is to tell udig request a custom format from wms 
for a specific layer and dont change the requests for other layers. I 
have accomplished this using layer blackboard and injecting some 
variable to check on the renderer side,


Hope this helps,
Best regards,

Devrim Baris Acar