[Flightgear-devel] Addressing the discontinuity that occurs when using discrete terrain altitude data during landing...
Hi! I've been working on a prototype flight simulator and I'm running into an issue I have no idea how to solve, so I decided to ask here since this very same problem might have been addressed in FlightGear. I want to model the landing of my aircraft. My problem lies in the altitude data. The data I have to use is a pixel map, which means that one square (which has around 100 meters side) has a certain value of altitude and the adjacent square has a completely different value... This means that if I try to land the aircraft in the border between two squares... it will either fall down or crash against this virtual discontinuity! I'm betting there's an obvious solution to this, but I'm out of ideas!... Any suggestions? Thanks! Antonio DISCLAIMER: This message may contain confidential information or privileged material and is intended only for the individual(s) named. If you are not a named addressee and mistakenly received this message you should not copy or otherwise disseminate it: please delete this e-mail from your system and notify the sender immediately. E-mail transmissions are not guaranteed to be secure or without errors as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete or contain viruses. Therefore, the sender does not accept liability for any errors or omissions in the contents of this message that arise as a result of e-mail transmissions. Please request a hard copy version if verification is required. Critical Software, SA. - Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.phpp=sourceforgeCID=DEVDEV___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Addressing the discontinuity that occurs when using discrete terrain altitude data during landing...
On 12/7/06, Antonio Almeida wrote: I've been working on a prototype flight simulator and I'm running into an issue I have no idea how to solve, so I decided to ask here since this very same problem might have been addressed in FlightGear. I want to model the landing of my aircraft. My problem lies in the altitude data. The data I have to use is a pixel map, which means that one square (which has around 100 meters side) has a certain value of altitude and the adjacent square has a completely different value... This means that if I try to land the aircraft in the border between two squares... it will either fall down or crash against this virtual discontinuity! I'm betting there's an obvious solution to this, but I'm out of ideas!... Any suggestions? In FlightGear, our terrain is modeled as an irregular mesh of triangles. We can lookup the terrain elevation at any point. As you move the terrain elevation value will change smoothly. It's not smooth in the sense of the first or second derivative, but that doesn't cause us a problem, especially on airport surfaces because we go to extra precautions to make sure all the elevation points are fitted to a smoothed surface (that approximates the original terrain data.) You might want to consider turning your grid of elevation heights into a triangle mesh (which you must have to do in order to render the data) and then sample your elevations off the mesh rather than the original data. Or maybe you could just interpolate between mesh points ... that might be even simpler. Regards, Curt. -- Curtis Olson - University of Minnesota - FlightGear Project http://baron.flightgear.org/~curt/ http://www.humanfirst.umn.edu/ http://www.flightgear.org Unique text: 2f585eeea02e2c79d7b1d8c4963bae2d - Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.phpp=sourceforgeCID=DEVDEV___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Addressing the discontinuity that occurs when using discrete terrain altitude data during landing...
Your altitude must be computed as the average of the surrounding squares or the position on the sloping line between two points if you really want it to match the graphics. On Thu, 7 Dec 2006 8:56 am, Antonio Almeida wrote: Hi! I've been working on a prototype flight simulator and I'm running into an issue I have no idea how to solve, so I decided to ask here since this very same problem might have been addressed in FlightGear. I want to model the landing of my aircraft. My problem lies in the altitude data. The data I have to use is a pixel map, which means that one square (which has around 100 meters side) has a certain value of altitude and the adjacent square has a completely different value... This means that if I try to land the aircraft in the border between two squares... it will either fall down or crash against this virtual discontinuity! I'm betting there's an obvious solution to this, but I'm out of ideas!... Any suggestions? Thanks! Antonio DISCLAIMER: This message may contain confidential information or privileged material and is intended only for the individual(s) named. If you are not a named addressee and mistakenly received this message you should not copy or otherwise disseminate it: please delete this e-mail from your system and notify the sender immediately. E-mail transmissions are not guaranteed to be secure or without errors as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete or contain viruses. Therefore, the sender does not accept liability for any errors or omissions in the contents of this message that arise as a result of e-mail transmissions. Please request a hard copy version if verification is required. Critical Software, SA. www.GlobalBoiling.com for daily images about hurricanes, globalwarming and the melting poles. www.ElectricQuakes.com daily solar and earthquake images. - Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.phpp=sourceforgeCID=DEVDEV ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
