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Eye height from runway

Postby tfreriks » Thu Jun 06, 2019 4:06 pm

I can adjust my eye-height inside the cockpit, but is there a way to raise the whole plane off the runway? I always feel like I'm laying down on the runway even on smaller aircraft. The eye level seems to be about 24". It is disorienting on landing. The centerline markers seem to be at least 30" wide. Which they aren't, of course.

Ideas?
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Re: Eye height from runway

Postby tdammers » Thu Jun 06, 2019 4:35 pm

Uhm, what? The eye position is simulated accurately; if you're flying a decent aircraft model, then it should look about right. The only thing you can meaningfully adjust is field of view (x / X); if the field of view grossly mismatches your physical field of view (i.e., the angle between the left and right edges of your monitor, relative to your eyes), then things will look distorted or out of proportion.
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Re: Eye height from runway

Postby tfreriks » Fri Jun 07, 2019 1:54 am

Take the Dash 8 for example: Eye level should be about 9'; it seems like it's maybe 5' at most. The 707 should be about 30'; it seems like 8' to me. The Citation II should be about 8'; it's about 6'. I have no hours in those, true, but I do in the Seneca and it feels like I'm 3' off the runway. I have a lot of C182 hours and it feels like 3'. These observations are especially true on landing. So, you're saying it should be accurate and my perception is off?
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Re: Eye height from runway

Postby tfreriks » Fri Jun 07, 2019 2:19 am

Clarification: runway centerline stripes are 36" fo precision approach runways. Maybe I'm used to 'real' non-precision runways which are only 18". Visual approach runways are 12". Hmmm. Maybe I answered my own dilemma.
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Re: Eye height from runway

Postby tdammers » Fri Jun 07, 2019 11:19 am

I don't have any real-life piloting experience, so I can't really comment on the perception; but I can tell you how the simulation works, and that the way it's modelled means the eye positions must be fairly accurate. If the centerline looks too wide, then that means it is modelled as being too wide, not that the eye position is wrong - if the latter were the cause, then you wouldn't be able to see the 3D dashboard properly, nor the cockpit windows, or else the entire 3D model would have to be wrong.

With some aircraft, you can even walk around the aircraft, and into the cockpit and cabin, and it's all modelled nicely, so you can actually verify that the whole thing is visually consistent.

So yes, runway markings being larger on large ILS runways than on small visual-only airfields sounds like the most likely explanation.
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Re: Eye height from runway

Postby WoodSTokk » Fri Jun 07, 2019 12:00 pm

tfreriks wrote in Fri Jun 07, 2019 1:54 am:The Citation II should be about 8'; it's about 6'.

Where you get the numbers?
The eyepoint is modeled around 6' and 2" above the ground with fully extented struts.
While at full compressed the eye is down to 5' and 6".
I dont know if thats correct. The numbers are the result of the model and i hope the model is accurate.

PS: i havn't model the Citation II, i have only improved it.
But all checks that i have done show a accurate model.
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Re: Eye height from runway

Postby tfreriks » Sat Jun 08, 2019 1:51 am

I just landed in the Citation II. When I stopped on the runway, eye level appears to be much lower than 6'-2" based on the way the how wide the centerline dashes look. I examined the plane from the outside, and it appears to be modeled perfectly. So, since there are only two explanations--low eye level or out-of-scale runway--could the runway be rendering inaccurately (too big) for some reason? Has anybody else reported this? It seems like I've noticed this on other aircraft.
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Re: Eye height from runway

Postby wkitty42 » Sat Jun 08, 2019 2:24 am

i've not seen any reports like this in the four or five years i've been here...
"You get more air close to the ground," said Angalo. "I read that in a book. You get lots of air low down, and not much when you go up."
"Why not?" said Gurder.
"Dunno. It's frightened of heights, I guess."
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Re: Eye height from runway

Postby WoodSTokk » Sat Jun 08, 2019 4:01 am

tfreriks wrote in Sat Jun 08, 2019 1:51 am:So, since there are only two explanations--low eye level or out-of-scale runway--could the runway be rendering inaccurately (too big) for some reason? Has anybody else reported this? It seems like I've noticed this on other aircraft.


I think it came from the texturing.
If you look into the FG directory under '/Textures/Runway', you will find 'pa_rest.png', 'pc_rest.png' and many more textures for the runway.
This textures will be stretched to the runway wide, so the centerline will be also stretched.
Also there are only one threshold with 6 markings left and right. There are actually no thresholds with less than 6 marks for smaller runways.
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Re: Eye height from runway

Postby tfreriks » Thu Jun 13, 2019 1:46 pm

I think you might be right, WoodSTokk. The asphalt texture is too course and it gives the illusion of being closer than you actually are. I'll try different textures and see if it changes the perception. Thanks! BTW: to answer a previous question: I got all the dimensions from aircraft specs and/or the FAA guidelines.
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Re: Eye height from runway

Postby tfreriks » Thu Jun 13, 2019 2:00 pm

I've examined the runway textures and they all seem to be the same in terms of how course the surface appears. Now, if the programming uses a smaller runway (the underlay, not the numbers) by default and expands it to fit the width of a precision runway, then that would account for the illusion; the texture elements would stretch with the value of expansion.

BTW: how would I change the assigned runway texture? Which XML?
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Re: Eye height from runway  

Postby WoodSTokk » Fri Jun 14, 2019 1:49 pm

The runway itself and the texture placement is defined in the BTG file. Actually its not possible to change it. Sorry.
To correct this, we need textures where only the painting is schown and TerraGear must place it like it does with the taxiways.
But until now, there is no people to step into this work.

PS: we actually have also no textures for orange and blue taxilines.
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Re: Eye height from runway

Postby xDraconian » Sun Jun 16, 2019 4:52 pm

I've actually already created new line textures (blue, green, orange, red) to align with the x-plane 11.30 spec. Just haven't finished incorporating them into the TerraGear workflow yet.
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