The DOGULEAN Planetarium 3.5.0

Requirements and Recommendations

Basic Requirements

You will need a browser that supports HTML5 and WebGL. That means that your underlying system must support OpenGL. A reasonably recent middle-of-the-line graphics processor should be good enough. I use a vintage 2014 Dell laptop (Inspiron 17 7000) with no problems.
On Linux the Wayland compositor protocol (XWayland) works a bit better than X.org (xOrg), though X.org works well enough. If your system supports Wayland, it is probably the default, anyway.
On Windows or Linux, the browsers Chrome, and Firefox are ok. MS Edge is ok except that, by default, it gives the wrong location after Set From GPS. The Planetarium does not support Internet Explorer or Opera. (Opera caches a lot of stuff without needing to and becomes slow to load.)
On Mac OS X or iOS, versions 12.5.2 or later of Safari perform well. Some earlier versions (10.x.x and 11.x.x) do not work. Chrome and Firefox should be ok if your device performs adequately. The last time I checked, all browsers on iOS were really Safari under different skins.
A reasonably high-definition monitor should suffice – higher definition is better.
You need a reasonable amount of memory. Allow at least 1GB for the Planetarium to use.

Touchscreens, Tablets, and Smartphones

The Planetarium gestures, sliders, and buttons to adjust numerical settings. Those will be more convenient than number inputs unless you really nead precise values.
I have had good results with reasonably recent tablets.
The planetarium will actually work on the recent smartphones I have tried, but it is not designed for such a small format. If you just want an app on your smartphone to help identify the stars and planets that you see in the night sky, there are many apps that you can use for that.

Troubleshooting

If the Planetarium Runs Slowly

The Planetarium does a lot of heavy lifting in terms of 3-D graphics – around 9,000 stars, 9 planets (counting the Sun), 30 moons, 6 sets of rings. If you are using a high zoom or an increased time rate, that will increase the load, because the Planetarium has to redraw the screen more often to keep the motion of stars and planets looking smooth.

Therefore, if the Planetarium seems to be running slowly, try the following.

If you have changed the zoom or the time rate, set them back to 1. You can do that by reloading the Planetarium page and clicking the “Reset to Default Settings” button on the dialog that appears.
If your browser has open web pages that consume a lot of cycles — pages with ads that keep changing, especially video ads, are likely culprits — close them.
If what you have done so far doesn't help, close other apps that may use a lot of cycles and restart your browser
As a last resort, restart your computer and try loading only the Planetarium in one browser or another.

If any of that works, play cautiously with zoom, time rate and other web pages and apps until you get a feel for what your computer can do. And whether it is a good idea to run the Planetarium on that machine.

If the Planetarium Goes Blank

The simplest possibility is that you are looking at the dark side of a planet or moon. Try increasing altitude, by using the Control Panel or by pressing the “up” button by the home planet name on the onscreen controls.
If that doesn't work, probably the Planetarium has been pushed too far and has suffered a numerical overflow. (Some numbers on the Control Panel may read “NaN” – for “Not a Number”.) Usually, reloading the Planetarium will fix this.
If reloading does not fix it, reload again and press “Reset to Default Settings”.
If that doesn't fix things, you can either clear the browser data or, if you are that kind of person, open the DevTools on the Planetarium page and clear the local storage. Then reload.
In either case, do send me an email saying what you did just before the problem occurred.

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