Re: [Flightgear-devel] Patch v5 - Rain & Snow
On Saturday 23 February 2008 19:53, Curtis Olson wrote: > On Fri, Feb 22, 2008 at 1:29 PM, Nicolas wrote: > > With OSG precipitation, I can't get in the same time snow and > > rain... > > > > No, there isn't factor in the motion of the aircraft... We can > > work to improve this. > > > > The origin and the wind have to be tested... and maybe adapted. > > Hi Nicolas, > > If I look very close with both snow and rain, I can now see that > the aircraft motion through the falling particles seems to be > correct ... it's subtle and sometimes hard to see depending on > the lighting and background color ... and subtle is probably good > for these effects. > > I think what confused me was that even at flying speeds, there is > still a downward elongation of the particles with rain which > tricks my brain into thinking they are falling straight down. If > the streaking could be made opposite the direction of motion some > how (???) I think that may make the visual effect more > compelling. I'm not sure if that makes any sense? > > But the overall effect of the snow and the rain is quite good. > Also, you work to tie this into the metar reports is also very > nice. Question: is it possible to tune the amount of snow/rain? > Perhaps a future update would be to ease slowly into snow/rain > rather than make an abrupt change (if that is possible to do.) > > I think if we could redo the draw order (or change the near clip > plane?) so that precipitation doesn't appear to be inside the > cockpit then I would be happy to see this new effect get > committed to cvs, and we can work on refining some of the subtle > perceptual details later. > > Best regards, > > Curt. Actually, even at typical car (automobile) speeds, transitions into and between rain and snow tend to be quite abrupt - perhaps just a second or two at ~50 mph. However, once you're in that weather type, the variations in density seem to be much slower. LeeE - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Patch v5 - Rain & Snow
Hi, Le samedi 23 février 2008 à 13:53 -0600, Curtis Olson a écrit : > Hi Nicolas, > > If I look very close with both snow and rain, I can now see that the > aircraft motion through the falling particles seems to be correct ... > it's subtle and sometimes hard to see depending on the lighting and > background color ... and subtle is probably good for these effects. > > I think what confused me was that even at flying speeds, there is > still a downward elongation of the particles with rain which tricks my > brain into thinking they are falling straight down. If the streaking > could be made opposite the direction of motion some how (???) I think > that may make the visual effect more compelling. I'm not sure if that > makes any sense? > > But the overall effect of the snow and the rain is quite good. Also, > you work to tie this into the metar reports is also very nice. > Question: is it possible to tune the amount of snow/rain? Perhaps a > future update would be to ease slowly into snow/rain rather than make > an abrupt change (if that is possible to do.) In fact, the METAR informations gives only the snow/rain quantity : low, medium, high. You can read these informations in /environment/metar/snow-norm or /environment/metar/rain-norm. The values are "double" : 0, 1/3, 2/3 and 3/3. But, I can simulate a smooth effect... to avoid an abrupt changement. > I think if we could redo the draw order (or change the near clip > plane?) so that precipitation doesn't appear to be inside the cockpit > then I would be happy to see this new effect get committed to cvs, and > we can work on refining some of the subtle perceptual details later. I improve the conversion rain/snow (I don't use the dew point...) I use only the temperature 0°C... it's easier and we don't need know the real temperature when the rain turns off snow... Particulary, if the temperature is between -1 and 1°C... At first, I try to add a clip plane... Then we will be able to try on refining this later... > Best regards, > > Curt. Thanks for your interest about my work... Regards, Nicolas - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Patch v5 - Rain & Snow
On Fri, Feb 22, 2008 at 1:29 PM, Nicolas wrote: > With OSG precipitation, I can't get in the same time snow and rain... > > No, there isn't factor in the motion of the aircraft... We can work to > improve this. > > The origin and the wind have to be tested... and maybe adapted. Hi Nicolas, If I look very close with both snow and rain, I can now see that the aircraft motion through the falling particles seems to be correct ... it's subtle and sometimes hard to see depending on the lighting and background color ... and subtle is probably good for these effects. I think what confused me was that even at flying speeds, there is still a downward elongation of the particles with rain which tricks my brain into thinking they are falling straight down. If the streaking could be made opposite the direction of motion some how (???) I think that may make the visual effect more compelling. I'm not sure if that makes any sense? But the overall effect of the snow and the rain is quite good. Also, you work to tie this into the metar reports is also very nice. Question: is it possible to tune the amount of snow/rain? Perhaps a future update would be to ease slowly into snow/rain rather than make an abrupt change (if that is possible to do.) I think if we could redo the draw order (or change the near clip plane?) so that precipitation doesn't appear to be inside the cockpit then I would be happy to see this new effect get committed to cvs, and we can work on refining some of the subtle perceptual details later. Best regards, Curt. -- Curtis Olson: http://baron.flightgear.org/~curt/ - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Patch v5 - Rain & Snow
Le vendredi 22 février 2008 à 10:40 -0600, Curtis Olson a écrit : > This is the first version I have taken a look at (v5) so I'm not > entirely sure what to expect. When sitting on the ground in KSAN > (METAR says rain and high winds) it looks like rain is coming straight > down as if there was no wind, but it looks like perhaps some snow > mixed in that is affected by the wind. But the temps I think are too > high for snow on the ground there (+53F/12C). Also, when the aircraft > moves forward the precipiation still looks like it's coming straight > down ... it doesn't seem to factor in the motion of the aircraft? Is > that still a todo item, or am I doing something wrong? Overall this > looks like it has a trememdous amount of potential so I'm not trying > to nit pick, just curious what I should or shouldn't be seeing at this > point in the development. > > Thanks! > > Curt. With OSG precipitation, I can't get in the same time snow and rain... No, there isn't factor in the motion of the aircraft... We can work to improve this. The origin and the wind have to be tested... and maybe adapted. Nicolas - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Patch v5 - Rain & Snow
On Fri, Feb 22, 2008 at 9:00 AM, Nicolas wrote: > Hi, > > Better and better... > > This patch permits to add snow and rain effects in using particle from > OSG. > > This improvement works with the METAR informations to enable / disable > rain or snow effects. > (intensity of effects is : low, meddium, high) > > The precipitations are stopped when the aircraft is above the cloud > layers. > > The rain preicipitation turn off snow precipitations when the ambiant > temperature is lower > than the dew point temperature. (the temperature depends on altitude) > > The wind influents the precipitations (speed and direction support). This is the first version I have taken a look at (v5) so I'm not entirely sure what to expect. When sitting on the ground in KSAN (METAR says rain and high winds) it looks like rain is coming straight down as if there was no wind, but it looks like perhaps some snow mixed in that is affected by the wind. But the temps I think are too high for snow on the ground there (+53F/12C). Also, when the aircraft moves forward the precipiation still looks like it's coming straight down ... it doesn't seem to factor in the motion of the aircraft? Is that still a todo item, or am I doing something wrong? Overall this looks like it has a trememdous amount of potential so I'm not trying to nit pick, just curious what I should or shouldn't be seeing at this point in the development. Thanks! Curt. -- Curtis Olson: http://baron.flightgear.org/~curt/ - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
[Flightgear-devel] Patch v5 - Rain & Snow
Hi, Better and better... This patch permits to add snow and rain effects in using particle from OSG. This improvement works with the METAR informations to enable / disable rain or snow effects. (intensity of effects is : low, meddium, high) The precipitations are stopped when the aircraft is above the cloud layers. The rain preicipitation turn off snow precipitations when the ambiant temperature is lower than the dew point temperature. (the temperature depends on altitude) The wind influents the precipitations (speed and direction support). Regards, -- Nicolas fg-patch.tar.gz Description: Binary data - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
