[Opensim-dev] DEM -> Raw

[Stefan Andersson]

I guess the point at 256,256 has to be known in four regions, if they are adjacent. fun, fun! :D
 
/Stefan Best regards,Stefan AnderssonTribal Media AB Join the 3d web revolution : http://tribalnet.se/ 



> Date: Sun, 25 May 2008 17:30:06 -0400> From: adam at deepthink.com.au> To: opensim-dev at lists.berlios.de> Subject: Re: [Opensim-dev] DEM -> Raw> > Adjacent terrain data is something I've been working on since Sean> raised the issue a few months ago. The problem is doing it in a> bandwidth friendly and accurate method which makes things very fun.> > Adam> > -----Original Message-----> From: opensim-dev-bounces at lists.berlios.de> [mailto:opensim-dev-bounces at lists.berlios.de] On Behalf Of dan miller> Sent: Sunday, 25 May 2008 5:29 PM> To: opensim-dev at lists.berlios.de> Subject: Re: [Opensim-dev] DEM -> Raw> > I know I've been out of the loop for a while, but I think it's worth> noting that last I looked at terrain, there was an odd issue.> > The terrain maps are 256x256, but to generate accurate terrain with> interpolation across a 256x256 region, you actually need 257 x 257> numbers. Otherwise, you can't properly interpolate one column and one> row. If you have access to the adjacent region's data, you could use> that, but in general I don't think that's possible (certainly not in> grid mode).> > When I looked at this late last year, I seem to recall that the> rendering software and the physics both did funny things along two> borders because of this issue. Just a heads-up in case anyone is> looking into it.> > > -danx0r> > > --- On Sat, 5/24/08, Frisby, Adam <adam at deepthink.com.au> wrote:> > > From: Frisby, Adam <adam at deepthink.com.au>> > Subject: Re: [Opensim-dev] DEM -> Raw> > To: opensim-dev at lists.berlios.de> > Date: Saturday, May 24, 2008, 3:32 PM> > Formats are:> > > > > > > > RAW = LLRAW (documented on the SL wiki) - terrible format> > best avoided> > unless you want to have artists edit the files by hand.> > > > R32/F32 - float[256,256] - read directly into/out of the> > heightmap with> > a conversion to/from doubles (we store all intermediary> > values as> > doubles internally, but save to/from files and DBs in> > single precision)> > > > BMP, PNG, GIF, WMF - saves to/from 256 colour grayscale> > image, uses IIRC> > a scale from 1-128m so each shade is 0.5m (may be 1-511, I> > forget. Test.> > Only really for exporting, importing is going to be lossy)> > > > JPEG - exports a false-colour coloured heightmap similar to> > the above.> > Same as the world map image.> > > > TER - Load-only, Terragen - 16bit precision.> > > > > > > > I personally recommend R32/F32 as most if not all terrain> > editing> > software can understand it. > > > > > > > > Re: USGS DEM (Important distinction as there are several> > varieties of> > DEM, including JDEM, EUDEM, etc) - I have been working on a> > supplemental> > terrain library for OpenSim which has support for USGS DEM> > files (and a> > variety of other more esoteric formats), however it is> > highly highly> > untested - use at own risk. Contact me if you want a beta> > copy.> > > > > > > > Regards,> > > > > > > > Adam> > > > > > > > From: opensim-dev-bounces at lists.berlios.de> > [mailto:opensim-dev-bounces at lists.berlios.de] On Behalf Of> > Diva Canto> > Sent: Friday, 23 May 2008 10:28 PM> > To: opensim-dev at lists.berlios.de> > Subject: [Opensim-dev] DEM -> Raw> > > > > > > > Hi,> > > > I have a couple of questions about terrains. Where can I> > get more> > information about these raw formats that OpenSim> > understands? I tried> > Googling, but couldn't really figure it out. Are these> > 32-bit floating> > points, one per what?> > > > Has anyone tried to produce RAW format files from DEM> > files?> > (http://en.wikipedia.org/wiki/USGS_DEM)> > > > Any info appreciated!> > > > Thanks,> > > > Diva /> > Crista_______________________________________________> > Opensim-dev mailing list> > Opensim-dev at lists.berlios.de> > https://lists.berlios.de/mailman/listinfo/opensim-dev> _______________________________________________> Opensim-dev mailing list> Opensim-dev at lists.berlios.de> https://lists.berlios.de/mailman/listinfo/opensim-dev> _______________________________________________> Opensim-dev mailing list> Opensim-dev at lists.berlios.de> https://lists.berlios.de/mailman/listinfo/opensim-dev
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