Very high-altitude icons and lines are clipped at wide zoom ranges

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What steps will reproduce the problem?

1. Put a placemark or graphical icon at 36,000 km altitude (36000000 meters).  
This is the 
altitude of a geosynchronous satellite.
2. Zoom out as far as GE will allow and try to view the placemark.
3. Placemark cannot be found, or it jumps in and out of view as the earth is 
rotated.  Note that 
lines drawn at high altitudes are clipped as well (see image).  

This clipping problem is probably due to poor depth-buffer selection.  There 
are methods for 
dynamically determining the correct buffer depth to render all elements in a 
scene.

This problem makes Google Earth impractical for viewing satellites and orbits.

What is the expected output or behavior? What do you see instead?
One expects to see the placemark or other features at satellite altitudes.

Which plugin version are you using?
Current as of Sept 8, 2009

Which browsers and operating systems are affected?
All Google Earth products (the app and plugins on Mac OS X Safari, Windows IE7, 
Firefox)

Please provide any additional information (code snippets/links) below.

Original issue reported on code.google.com by john.co...@gmail.com on 22 Oct 2009 at 4:15

Attachments:

• clipped_lines.jpg

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I think you'll find that that this is another example of the "Near Clipping 
Plane"
bug reported as issue 120 - has been open since December and "confirmed" by GE. 

Original comment by gpsanima...@gmail.com on 6 Nov 2009 at 8:59

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Update: Unfortunately this bug still persists in Google Earth 5.2.1.1329 (beta)

Original comment by john.co...@gmail.com on 16 Jun 2010 at 4:06

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[deleted comment]

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Original comment by jli...@google.com on 16 Jun 2010 at 8:36

• Changed state: Confirmed

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I encountered the same issue within a mission planning tool which includes a 
Google Earth API view showing satellites positions: http://asp.ashtech.com/wmp/
It is not possible to see all satellites positions at a given time, even 
satellites from the lowest constellation (GLONASS, ~19,000 km).

Using Google Earth Plugin v6.0.0.1735.

Original comment by ddc.rob...@gmail.com on 8 Feb 2011 at 8:40

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Clipping was fixed for many geometry types in 5.2.1.1547 (including the 
original test case), but the remaining types are forthcoming.

For the satellite example in Comment 5: can you be more specific about your 
issue? I see points representing satellites, even up to GPS, and lines 
connecting the viewing location to satellites above the horizon. I couldn't see 
any obvious clipping problems.

Original comment by bcke...@google.com on 11 Mar 2011 at 3:04

• Added labels: Internal-2828490

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Here's a capture to illustrate Comment 5 (see attached file).

Therefore, I think this may be due to the plugin being way too large compared 
to its height. In that case, I should add a KML export and/or full screen 
button.

Original comment by ddc.rob...@gmail.com on 11 Mar 2011 at 7:29

Attachments:

• SatellitesView.png

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Thanks for responding. That looks to be a totally separate issue than the one 
at hand (clipping by the far plane vs clipping by the edges of the viewport 
(and possible incorrect projection)).

With that in mind, would you mind filing a new report for your issue? A 
simplified test case where the problem is instantly apparent would also be very 
helpful.

Original comment by bcke...@google.com on 12 Mar 2011 at 2:46

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I am still having this issue as of version 6.0.0.1735

I made a quick test case in the code playground using a skysphere (this is the 
issue I am currently running in)

http://savedbythegoog.appspot.com/?id=f818f54ff3a87aee68630b833f4de936a3c494e4

Camera is set at an attitude that makes the skysphere being clipped near the 
horizon. If you zoom out a bit, you will see the whole model.

This is reproducible on any hardware using any browser as far as I know.

Attached, the Javascript code to run the test case if needed.

Original comment by xtas...@gmail.com on 14 Mar 2011 at 10:07

Attachments:

• clipping-testcase.js

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I am able to reproduce that problem as well. We will use the test case in 
Comment 9 to make sure that the scene is clipped optimally.

Original comment by bcke...@google.com on 29 Mar 2011 at 10:19

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[deleted comment]

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Also, please consider reviewing issue 607 
(http://code.google.com/p/earth-api-samples/issues/detail?id=607) as it may be 
related (clipping bug).

Original comment by xtas...@gmail.com on 30 Mar 2011 at 8:48