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Papi Lights

Graphics issues like: bad framerates, weird colors, OpenGL errors etc. Bad graphics ar usually the result of bad graphics cards or drivers.
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- what OS (Windows Xp/Vista, Mac etc.) are you running?
- what FlightGear version do you use?
- what graphics card do you have?
- does the problem occur with any aircraft, at any airport?
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Re: Papi Lights

Postby Thorsten » Wed May 22, 2019 6:28 am

At this kind of distance and zoom, the lights would've been antialiased out.

Actually not - since they're point sprites, we can freely set the pixel size based on distance (that's kind of the point of point sprites - pun intended).

So usually the only reason you don't see a light is that the equations say you should not see it - but we are technically able to show it from 1000 miles out.

So both disc size and disc color in combianation are supposed to represent the light intensity, and since the Airy disc is rendered there's what you'd call 'bloom' aplenty (I don't like the term 'bloom' - the eye doesn't do that kind of thing - to the part that it's Airy disc we render it, but to the part that's what CCD chips do, I don't think we need it).

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Re: Papi Lights

Postby Robertfm » Wed May 22, 2019 9:17 am

ludomotico wrote in Tue May 21, 2019 11:13 pm:

According to my real life experience, you will only get a light intensity similar to the one this video shows if you set a forest on fire each time an aircraft approaches the runway.

Check this video under similar light conditions:

In my opinion, based not only on that video but also my real life, while the sun is high, you can only guess the PAPI lights on short final and distinguish colors on very short final.

Let me compare distances in both videos. Both videos show similar light conditions on the same aircraft, i.e, same speeds.

- FSX in your video shows PAPI lights from minute 8 and touchdown happens on minute 14. PAPI lights are shown during about 6 minutes before landing
- The real video above shows PAPI lights from minute 9 and touchdown happens on minute 10:30. PAPI lights are shown during about 1:30 minutes before landing.

In my opinion, FSX shows PAPI lights from a distance about 4 times longer than you'll see them in real life.

Thank you for that explanation.
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Re: Papi Lights

Postby Robertfm » Wed May 22, 2019 9:21 am

Thank, now I understand the issues I won't worry about it. My confusion as I said at the outset was the view I got when using my laptop.
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Re: Papi Lights

Postby wkitty42 » Wed May 22, 2019 1:53 pm

if you haven't done it yet, please click the green check mark on the post that helped you to solve this problem ;)
"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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