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As an experiment I was trying to create a scene with a few simple objects but with extremely large dimensions. Think planet and moon sized objects and a couple of human scale objects in the foreground.

  • I have units set to metric.
  • I have set my camera's clipping end value 10000km
  • I moved the camera to 0, -9000km, 0 looking toward the origin (I can see the 3D cursor there)
  • I create a UV sphere at the origin with size 4000km.

The sphere is not visible.

I've tried a number of variants to no avail.

What am I missing? Or is this just out of scope for Blender for some reason.

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    $\begingroup$ Works fine for me.. But I doubt physically accurate scales will really change the visual result a lot, so you might want to scale your scene down (either uniformly or just make the plant/moon things as smaller, closer objects with roughly the same apparent size). $\endgroup$ – gandalf3 Jan 26 '15 at 0:15
  • $\begingroup$ Wow, that works for you? I want to keep the original size because I want to leverage some simulation software that I wrote (fortunately in Python w/ NumPy) a while back where changing the scales would require an enormous amount of debugging. I'm on Blender 2.73. I guess I'll try to debug my scene better. $\endgroup$ – Chuck Jan 26 '15 at 5:26
  • $\begingroup$ this answer is related $\endgroup$ – sambler Jan 26 '15 at 5:52
  • $\begingroup$ @Chuck Perhaps you could upload a file where it isn't working? Perhaps something else is going on.. $\endgroup$ – gandalf3 Jan 26 '15 at 6:41
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    $\begingroup$ Z-fighting isn't the only problem you'll face with this type of setup. Floating point numbers only use roughly 6 decimal places(give or take a bit!) As soon as you start applying math to these numbers you will have some serious round-off errors creeping in every-time you do any math,(shadows, z-fighting, position info, etc...) Using double floating point precision can help to avoid this but now you are doubling the memory requirements of your software and the GPU might not even support anything beyond 32bits so visual artifacts are almost guaranteed for every aspect of what you are doing $\endgroup$ – MarcClintDion Jan 27 '15 at 2:41
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You need to change the clip distance not only on the camera, but on the viewport as well.

enter image description here

enter image description here

Also if you are going to deal with those magnitudes, you might want to change the scale, both on the Viewport and the scene->units.

NOTE: watch out for Z-fighitng when rendering long distances. Read:

Weird shading effects when rendering at long distance

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  • $\begingroup$ again, FTW! Thanks. I actually have more objects that will be closer to the meter scale than large objects but I'll play around both ways and see how it goes. $\endgroup$ – Chuck Jan 26 '15 at 13:46
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    $\begingroup$ watch out for Z-fighitng when rendering long distances. Read: blender.stackexchange.com/questions/21647/… $\endgroup$ – cegaton Jan 26 '15 at 17:01
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    $\begingroup$ Thanks again. I've had similar problems in my own OpenGL code. I know not to set the near plane too close to the camera. So far not a problem in my scene. $\endgroup$ – Chuck Jan 26 '15 at 17:26

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