[thredds] thredds WMS vector wind layer alone without velocity image

• To: "thredds@xxxxxxxxxxxxxxxx" <thredds@xxxxxxxxxxxxxxxx>
• Subject: [thredds] thredds WMS vector wind layer alone without velocity image
• From: Ivan Price <Ivan.Price@xxxxxxxxxxx>
• Date: Wed, 26 Sep 2012 09:13:21 +0000

Hi there,

We are using the excellent wind direction auto-variable feature of THREDDS, 
whereby after defining our 'eastward_wind' and 'northward_wind' we are able to 
get the direction and strength map via the layer 'wind'.

my question:   we have seen we can ask for the map in various styles, affecting 
the colour palette and scale of the underlying wind velocity image. we would 
like to know if it is possible to remove altogether the underlying image, 
leaving only the wind direction arrows. I have thought about defining a palette 
with only a single transparent colour, but I'm not sure if that is possible as 
the palettes don't seem to support alpha values.

And perhaps in the same question if anyone has ever investigated having the 
arrows to reflect the wind velocity in the typical 'quiver' type way.. this has 
probably been discussed before but I can't find any reference.

thanks and regards

-ivan
NOVELTIS

• Follow-Ups:
  • Re: [thredds] thredds WMS vector wind layer alone without velocity image
    • From: Kyle Wilcox