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overhead/naked eye simulations not rendered. - Printable Version

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overhead/naked eye simulations not rendered. - razvan - 2019-06-23

Hi Greg,

Something odd that's happened several times on my laptop (Thinkpad T470s with high DPI/Windows 10)  ST 4.0d. The naked eye or overhead sky simulations are not rendered (the atlas is fine). A "Visual Sky Simulation" window appears in the task bar but as if it were minimized. Any attempt to bring restore its size or bring it to front does not work (the window is not rendered). Hitting Alt-Tab shows what I'm attaching: a mostly black screen with some white lines, as if something were rendered block by block and it stopped. Always in the same position. It does not matter if I try to open the sky simulations directly or if I open the atlas first (which works). If I do the latter, when I chose one of the two sky simulations from the dropdown box at the top, the window is minimized and I'm in the same situation as if I opened it directly. In case it matters, the minimized window is response to right-clicking & closing it.

I upgraded the display drivers (details below). I turned off display scaling. No change. I don't remember if it worked in the past (I bought it a month ago) because I'm also using ST4 on a Dell desktop where everything works (the video card is different) and mostly used the laptop for planning. I did notice the problem but in the past but am not 100% sure if it worked at all. 

I realize it's hard to debug these things from a distance so my questions are: (1) have you heard about such a problem in the past and (2) is there any application logging to enable or anything I can do to further investigate it? As a programmer, I'm thinking perhpas there's some commonality in the rendering of the sky simulations that is not used by the atlas. 

Thanks for any support you can provide. 



Intel® HD Graphics 620

Report Date: Saturday, June 22, 2019
Report Time [hh:mmConfuseds]: 8:28:58 PM
Driver Version:
Operating System: Windows* 10 Home (10.0.17763)
Physical Memory: 24472 MB
Vendor ID: 8086
Device ID: 5916
Device Revision: 02
Graphics Output Protocol (GOP) Version: 9.0.1061
Current Resolution: 2560 x 1440

Processor: Intel® Core™ i7-7500U CPU @ 2.70GHz
Processor Speed: 2904 MHz
Processor Graphics in Use: Intel® HD Graphics 620
Shader Version: 5.1
OpenGL* Version: 4.5
OpenCL* Version: 2.1
Vulkan* Version: 1.1.93

* Microsoft DirectX* *
Runtime Version: 12.0
Hardware-Supported Version: 12.0

* Devices connected to the Graphics Accelerator *
Active Displays: 1

* Built-in Display *
Display Type: Digital
DDC2 Protocol: Supported
Gamma: 2.2
Connector Type: Embedded DisplayPort
Device Type: Built-in Display

Maximum Image Size
Horizontal Size: 12.2 inches
Vertical Size: 6.69 inches

Supported Modes
2560 x 1440 (60p Hz)

Power Management Support
Standby Mode: Supported
Suspend Mode: Supported
Active Off Mode: Supported

00 FF FF FF FF FF FF 00 30 AE AA 40 00 00 00 00
00 1A 01 04 A5 1F 11 78 EA D1 E5 A4 55 4E 9D 26
12 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01
01 01 01 01 01 01 1C 61 00 C8 A0 A0 3C 50 28 20
AA 00 35 AE 10 00 00 18 1C 61 00 C8 A0 A0 3C 50
28 20 AA 00 35 AE 10 00 00 18 00 00 00 0F 00 05
09 3C 05 09 3C 1E 0A 00 06 AF 00 00 00 00 00 FE
00 42 31 34 30 51 41 4E 30 31 2E 35 20 0A 00 23

RE: overhead/naked eye simulations not rendered. - theskyhound - 2019-06-23


The code to handle multiple monitors and saving windows states and positions is complicated, and I suspect something got corrupted.

Try this:

1. Close SkyTools
2. Find your "SkyTools 4" folder in your Documents
3. Delete the file called "ddsi.bin"

This will cause you to lose some of your settings, but none of you actual custom data. Let me know if the problem persists.

RE: overhead/naked eye simulations not rendered. - razvan - 2019-06-23

Hi Greg,

Your fix worked, thanks!

And based on a hint in your reply, now I know what happened. I share my ST4 UserPath between the laptop and a desktop, via Dropbox (you will recall a different thread about this).  About two weeks ago I had a few conflicts in Dropbox (I have the paid version with a longer history so was able to check the history) specifically notifiy.bin, ddsi.bin, dds.bin and obs.bin. This must have been the start of the problem (I nearly forgot it because it didn't cause any visible issue at the time, obviously I didn't try the sky simulation) and it must have been my mistake, perhaps I started ST4 before a sync finished or on both devices at the same time. I promised to be careful but it's possible that it happened. As HAL 9000 put it, “It can only be attributable to human error”  Smile

I had a suspicion that the cause was that the desktop has dual monitors. What if I open the simulation window on the second screen on the desktop, exit ST4 there, then open ST4 on the laptop which would try to show the window on non-existent second screen? I tested it just before posting this and I couldn't reproduce the problem. The simulation windows opened fine on the laptop, even if previously positioned on a second monitor on the desktop. So maybe it was something else or, if still involving dual monitors, at least a different scenario.

Thanks again and hope this helps anyone who runs into the same issue.

RE: overhead/naked eye simulations not rendered. - theskyhound - 2019-06-23


You are going a bit into unexplored territory with the data file sharing. The window placement should be the only problem though, although I would take care not to use it simultaneously on two different computers.

This is why the chart window placement became complicated though, handling the case where a monitor disappeared or changed resolution since the window was last opened. It is designed to handle these situations, but I had a lot of trouble getting it to work the way it was supposed to. There may still be a bug in there somewhere, so if you see this again, I'd like to hear the circumstances that led to it.

One other thing though: are both computers running the same OS? Windows 10 handles multiple monitors a little differently.

RE: overhead/naked eye simulations not rendered. - razvan - 2019-06-23

Yes, both are Windows 10.

Apart from this case (most likely caused by me having ST4 running on both devices inadvertently), sharing the user path works great. I can do some planning work in the subway or a lunch break and when I get home I can continue on the dual-monitor desktop. And then, when I live to a dark sky, I have the latest already on my laptop.