ANGLE parameter

[Frank Warmerdam]

Blammo wrote:
> All,
> 
> I'm trying to get a test going using the ANGLE map parameter but not 
> having much success.
> 
> I found a reference to a "non-GDAL" raster, (what the heck does that 
> mean) 

Bob,

MapServer supports reading rasters via means other than GDAL.
But there are a number of raster features which are only available
when operating on rasters read through GDAL.

I believe ANGLE support is one of those things that doesn't work
for non-GDAL rasters.  BTW, with GDAL enabled I think essentially
all raster support is through GDAL so this isn't usually a big
issue.

 > related to raster warping in the how-to for raster data.  I
> suppose this relates somehow to my source data, but how.
> 
> Hmm, just found the requirement for the Projection info to be present 
> for each Layer and the Map.  I'll try this out in the morning.

This certainly used to be a key requirement.  I think I have been
trying to relax it in the related "nonsquare pixel" ability which
is closely related to how angles are implemented.

> Question, it says in the MAP file doc's that it doesn't work with 
> MapServer CGI, can the ANGLE param be passed in via the request?  I 
> tried a couple of variations earlier today,
> 
> map_test_angle=0 (no effect on rotation)
> map_test_angle=1 (blank image)

Hmm.  It may be that I did not add support for setting ANGLE from
cgi variables.  I never use this myself, and I'm pretty uncertain how
this is supposed to work in MapServer.  But if doing the above caused
a blank image, it must be doing something!

> and the parameter seems to be heard by the MapServer but anything other 
> than a value of "0" returns an empty image.  This was before discovering 
> the info about the projection info requirements however.  So maybe it 
> will work after all.

Right, please report back if things still don't work when you have projections
on your map and layers.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGF, http://osgeo.org