Home cockpit - multiprojector screen problems setup (stutters)

[sisoffi]

Hi at all,
I'm trying to configure my system for a visual screen home cockpit wth my optoma GT720.

My pc is:
I7 3770K OC 4.2
SSD 256gb
16GB RAM
ASUS ROG gtx1070 card.
win7 64but + Lockheed Martin Prepar3D clen install.

cables at 1070: 3 projectors 2xHDMI 1 xDP (via passive adaptor dport -> hdmi) surround mode 4800x1200
1 service monitor (vga via dvi-d -> active vga) 1280x1024

TEST:
making in the service monitor test everything is perfectly set and very smooth, block at 30fps.
(no addons for the moment)

for my visual 220° i need to create a surround screen with 3 disancor views front - left and right (with warp and correct hfov and vfov headings).
At this point altouhgt fps remain blocked at 30 start stutter especially on left and right views.

i tried to test some affinity maks and tweak on configuration files but nothing.

some questions:
CPU dont follow the high request need to run smooth?
GPU with bad setup cable (somebody allert me to use one Displayport Hub split to 3 hdmi in one channel
and put service monitor connect to Inel Graphic board)

impossible to obtain a very smooth view with only one pc? need to pass with 3 pcs?

many thanks to all for helps.
Simon

[sagrada737]

Hello Simone,

Congratulations on your willingness to take on the challenge of a multi-projector system for your flight sim.  It can be a daunting task to configure a single computer system to yield an efficient multi-window display that has decent frame rates and good image quality - something you are already discovering.  As an encouragement to you, there have been many postings on this forum over the years covering many of the detail you are interested in, so it would be helpful for you to dig around this forum to see what others have done with similar sim setups.

From what you have described of your computer system, you should be able to achieve "reasonable" multi-projector 220 display performance operating in a multi-window mode with P3D.  The question for you to consider is...   What is reasonable performance?   

As you have already discovered, it is almost impossible to achieve perfectly smooth performance with the system configuration you have - frame rates and associated stutters being one of many issues you might see.  Since you did not mention any addon scenery, I assume you are using the default P3D scenery.   Realize that adding scenery, and other addons to your setup can greatly affect computer system performance, which can in turn greatly affect the display performance and quality.   

You are on the right track with the "tweaking" of P3D settings, and related prepar3d.cfg file settings, such as Affinity Mask.   However, there is no singular magical solution that will solve display performance issues - it is typically a combination of settings that ends up yielding the "best compromise" in system performance and display quality - these things are typically unique to each person's Sim configuration and are subjective as to what you want to achieve in your own Sim.

As a suggestion...   Perhaps the best way for you to proceed is to start off with reduced performance/quality settings in P3D as adjusted within the Graphics and Scenery settings windows.  The idea being for you to achieve "stable" display performance with your multi-projector configuration, with the additional system monitor.   When I say stable, I mean that you don't have any computer system crashing issues or erratic behavior in P3D.   Having established a basic set of settings in P3D, you can then proceed to  incrementally modify settings to see the impact on display performance.  As you may have discovered, there are a few good YouTube presentations on tweaking P3D, but none of them are perfect as might be related to your particular system setup.

You asked the question about going to three (3) PCs...   This is certainly one solution that a few are using for their Sim setups, but be aware that there are many other complexities with such system configurations using multiple computers for a Sim setup - cost and maintenance issues as an example, not to mention the learning curve associated with the greater complexity.  My suggestion would be to start simple and get a configuration that is working correctly, and one that is stable - then explore greater system complexity to achieve better (subjective) results.

Keep in mind that what you are wanting to accomplish is possible with a single computer system controlling a multi-projector setup.   But what you may also want to keep in mind is the fact that when you go with a multi-window mode for your Sim display, it places a huge processing burden on your CPU and GPU, the outcome of which is a level of performance and quality that will never be perfect - it is all a compromise.

I think you  live in Italy.   If it's possible, try to find someone in Italy that already has a Sim running a multi-window projector setup, visit them and compare notes on what they have done.  It is truly difficult trying to solve these kind of Sim issues on the forums, but don't give up, as resolving Sim display issues can take some time.

As for my Sim setup...   I run P3D v3.0 with Sim-Avionics B737-800 flight model.   I use a single computer (much like yours) for P3D and another less capable computer for the flight model.   I have three Optoma GT1080HD projectors driven by a GTX980ti (about 10% slower than a 1080).  I use a DVI and DisplayPort adapters plus the HDMI output to interface via HDMI to the projectors.  My display is 220 degrees using PixelWix AutoBlend with EVO (same as ImmersivePro). I use ORBX Base, LC, and Vector scenery, some MegaScenery, REX HD Airports, HD Trees, and some HD airports.  I use ActiveSky Next for weather.   And yes....   sometimes I have stutters and lower frame rates depending on what region and/or airport I am operating at.   But overall, I am very pleased with the display result.   i should add that I don't use a separate system monitor on the P3D computer.

Keep us posted on your progress, and don't hesitate to ask detailed questions on the forum.   There a lot of good guys that have much more experience with multi-window setups using multi-projectors for their Sim display.  I'm sure you will get additional comments that may be helpful for your Sim project.

Regards,
Mike

[sisoffi]

Mike.
thank you for your precious help.
in fact I'm noticing that the setup is really subjective. from hours of test i obtain a stable 30fps with 3 undocked views (one our view is under the 3 in panel only mode) with F22 at full speed at even with photoreals and airports addons (some sporadic microstutters but tolerable but not lag).

I turn off HT on my 3770k with no affinity mask.

These my further considerations:

GPU
my asus strix rog gtx1070 has 1xDVI-D - 2xHDMI - 2xdisplayports (DP)

I am currently using 2hdmi + 1dport->hdmi (passive)
1xDVI-d-> vga active for the service monitor.

I read problems of one bug that nvidia has for vga old monitor.
reading and studying it is preferable to use in order:
dvi-d - hdmi - dports

i noted that if i use dp->vga active the resolution stay under 1024x768 (and not 1280x1024)

somebody even use a DP>3HDMI multiport in order to have in only one channel dataflow and dont lose data.
This is i hink for GPU taht dont have ports sufficient for channels, i dont think my gpu have trouble managing channels or lost dataflow.

MONITOR HERTZ REFRESH RATE
somee body use a tweak about 30Hz rate for the refresh monitors.
I tried with OCR and reduce 30hz from 60hz monitors with no performance.
I dont know if projector can go at 30Hz and obtain huge performance.

SSD and dataflow
actually i have SO and P3D in c: ssd (samsung 850evo 250gb)
somebody use 2xSSD in stripe mode for high read data

e: seagate 7200RPM for addons sceneries
my test was before with clean install of p3d running only in c: (in mobo sata is connected to 6gb port) test report ok
add sceneries from e: (sata port in 3gb)  test report ok with no loss data flow

i've another 1tera disk eventually to put in raid mode.
Is this the case to use striped disk and probaly obtain better performance in read/write load time?

many thanks,
Simone

[sagrada737]

Hello Simone,

From your reply, it looks like you are making progress.  Keep tweaking the parameters - it is an ongoing process.   Don't be surprised if you make an adjustment to one or more settings, as sometimes such changes can degrade performance.   Keep good track of the changes you make, so you can go back to what worked well before.   So-called micro-stutters will show up from time to time.  I have found that settings that worked well one day, seem to show differently on another day. 

One thing I have been doing is to delete the contents of the Shader directory (leaving the Shader directory empty), which in my case, seems to improve the smoothness of the flights.   It is easy to do, and new shader files are built by the software as it needs them.

To compare notes...   Here are the settings I have in my P3D GRAPHICS page for the "Image and Texture Quality" settings:

FXAA:  OFF
MSAA:  8 Samples
Texture Finishing:  Anisotropic 8x
Texture Resolution:  High 2048 x 2048

Of course, these kind of settings are subjective, and may not be suitable for your setup.

I also use NVidia Inspector for the standard Prepar3D settings.   Some use NVidia Control Panel for settings changes.   It seems that everyone has a tweak that works for them with their particular Sim configuration.

Keep up the good work, and keep us posted on what has worked for you to get smooth display performance - especially the "shimmering" that is typical at airports in P3D.

Best Regards,
Mike

[sisoffi]

Hi Mike,
i proceed wth my test. the best setup running now is

HT=off (4 CORES)
no OC for the CPU
affinity mask=14

on P3D
medium high setting, dont have a drop down frash but is costant from 25 to 30 (fps block to 30 in vsync ON).
test on photoreal scnenery ad one airport. I need to test a long fly to see the VAS usage from departure to arrival.
in Nvidia control panel set for P3D program to vsync mode ADAPTIVE.

The problem i think remain the 60hz, somebody suggest me o put projectors in 30Hz, but im worry that come to flash and damage them.

I will go ahead with other tests.

Many thanks
Simone