TrueMarble - osgEarth_package

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bclay bclay
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TrueMarble - osgEarth_package

I am trying to create an osgEarth project that gives a smooth transition from space to ground.  TrueMarble images are available in a variety of resolutions that can be used in an earth file to make the transition.  I am trying to use osgEarth_package to create tiles to do the same thing for better load time.

Is there any benefit to tiling the various resolution TrueMarble images with a few levels and letting the earth file make the transition at certain altitudes over just tiling the highest resolution TrueMarble to several levels?

Bruce
bclay bclay
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Re: TrueMarble - osgEarth_package

Follow on question.

Is there any rule of thumb when generating tiles to set min and max levels for a transition from a 250m per pixel to a 1 meter per pixel image.  We don't have full coverage at 1 meter so we would move from TrueMarble 250m down to NAIP 1m.
gwaldron gwaldron
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Re: TrueMarble - osgEarth_package

In reply to this post by bclay
Bruce,
I presume (best guess) that True Marble is derived from a single source resolution (probably 15m). Their lower-resolution options are probably just downsampled from that rather than being collected separately. Therefore it likely will not make any difference -- just generate you tiles from the highest resolution you have.
Glenn Waldron / Pelican Mapping
bclay bclay
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Re: TrueMarble - osgEarth_package

Glenn:

it is more a question of when (what elevation) to change from one dataset to the other.  Since we don't want to attempt to use 1 meter data while zoomed out to the world view.  We use the TrueMarble when zoomed out then switch to Landsat (15m) where we have that or NAIP (1m) where we have that.  

A problem we are having is that osgEarth_package does not seem to be generating tiles for the best resolution and in some cases the tms.xml file has invalid bounding box so the layer does not show in the earth viewer at all.

Bruce