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The influence the wind has on the jumper's speed

Posted: 01 Feb 2011, 19:59
by pajkul
Hi!
I'm not sure if it is possible that the difference in the jumper's speed on the inrun can be 2,2 km/s, depending whether there's 2m/s front or back wind. I'm not a real skijumper nor haven't noticed anything like this in real life on TV. Can anyone verify this?

Posted: 01 Feb 2011, 20:03
by doubleffect
I noticed this as well. When we have a tailwind, the jumper gets a higher speed after take-off. I don't think this reflects how it is in real life, this is probably the game engine fault that it somehow adds to the speed of a jumper when the wind is from the back and it shows decreased speed when the wind is frontal.

Posted: 01 Feb 2011, 21:27
by EgyLynx
... yeah... but i think it is wind factor...

Posted: 01 Feb 2011, 22:31
by Jussi Koskela
Why wouldn't the wind have effect also during the inrun?

Posted: 01 Feb 2011, 22:33
by Muga
I dont remember the year but in Planica they had so much frontwind that they were only 95km/h fast! And this wasnt only because of the start gate.

Posted: 01 Feb 2011, 22:43
by Konsta Siivola
If you have tailwind, the air stream wont flow so fast against you and of course it gets you the faster speed..

Posted: 01 Feb 2011, 23:14
by pajkul
I'm not saying that there should be no influence on the jumper speed during the inrun part of the jump, just asking if the influence rate implemented in the game corresponds to the real life.

Posted: 01 Feb 2011, 23:28
by Jussi Koskela
There might be some deviation compared to the reality as aerodynamics is pretty much impossible to simulate 100% accurately, but I guess that my approximation is not that far away.

Posted: 02 Feb 2011, 00:32
by EgyLynx
is it better beta 2? :roll:

Posted: 02 Feb 2011, 11:01
by EyTschej
The wind has close to zero influence on the inrun speed - see reality (compare inrun speeds of competitions with chaning winds).

I've raised this issue in DSJ3 before, but Jussi never really wanted to give a straight answer on this. :( In my opinion, Jussi simply uses that influence on the DSJ jumper in the inrun so he doesn't have to add a "gate feature". If the wind had no influence on the DSJ jumper in the inrun, we might jump way too far where it would be totally unrealistic not to crash and burn.

I've suggested a long time ago that the wind should only affect the DSJ jumper from the end of the inrun on and that gates should be added to the game. After all, this would simply be realistic - and isn't realism DSJ's most appreciated trademark? :wink:

Posted: 02 Feb 2011, 11:52
by Severin
EgyLynx wrote:is it better beta 2? :roll:
One remark: It seems pretty obvious that you use some kind of online translator to post your replies here EgyLynx, but the problem with that is that about 3/4 of the sense of your posts gets completely lost. So if you're able to read the english posts here, you should pretty much be able to write english with simple words. So please stick to that instead of using a translator and we all could better understand what you mean ;)

Posted: 02 Feb 2011, 12:26
by Jussi Koskela
EyTschej wrote:The wind has close to zero influence on the inrun speed - see reality (compare inrun speeds of competitions with chaning winds).

I've raised this issue in DSJ3 before, but Jussi never really wanted to give a straight answer on this. :( In my opinion, Jussi simply uses that influence on the DSJ jumper in the inrun so he doesn't have to add a "gate feature". If the wind had no influence on the DSJ jumper in the inrun, we might jump way too far where it would be totally unrealistic not to crash and burn.

I've suggested a long time ago that the wind should only affect the DSJ jumper from the end of the inrun on and that gates should be added to the game. After all, this would simply be realistic - and isn't realism DSJ's most appreciated trademark? :wink:
The gate feature has nothing to do with this. It's basicly missing to keep the hill records clean of different gates (anyway I might include it to practice mode soon).
In reality the wind has atleast a small effect on the inrun speed. The structure of the inrun blocks the wind a bit, but I don't have any numerical data about this. It's very easy to put a magic coefficient there once we know a proper value. :roll:

Posted: 02 Feb 2011, 13:03
by maciej53
I think wind should only speed up/down only up to 1km/h.

Posted: 02 Feb 2011, 13:50
by EyTschej
Jussi Koskela wrote:The gate feature has nothing to do with this. It's basicly missing to keep the hill records clean of different gates (anyway I might include it to practice mode soon).
In reality the wind has atleast a small effect on the inrun speed. The structure of the inrun blocks the wind a bit, but I don't have any numerical data about this. It's very easy to put a magic coefficient there once we know a proper value. :roll:
The gate feature would require an AI jury for competitions, I understand. Adding a gate feature to practice mode would be a first step. And besides: The gate feature, from what I can tell, is one of the most wanted additions to DSJ anyway, so it should be worth the time and work ;)

The influence in the inrun is much too high the way it currently is. It's really close to zero because tailwind won't have much influence anyway - the inrun is blocking that wind. ;)

Headwind also can't be that much of an influence because the FIS doesn't include this in their wind points. Changing the gates has a much bigger influence on the inrun speed then the wind itself. You could have an extra 0.5 km/h with one gate extra, but the difference between head and tail wind from the same gate should be about 0.1 km/h, I believe. Severin might be able to give us more insight into this matter, I would hope.

Posted: 03 Feb 2011, 12:10
by maciej53
Severin, could you tell us how does wind on inrun influence on you?