https://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&feed=atom&action=historyUser talk:OhioBob - Revision history2024-03-28T13:42:40ZRevision history for this page on the wikiMediaWiki 1.29.0https://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62831&oldid=prevXZise at 21:09, 18 May 20152015-05-18T21:09:31Z<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like <nowiki>{{Body data/pressure approx|</nowiki>''body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like <nowiki>{{Body data/pressure approx|</nowiki>''body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:One of the reasons why you might have been fooled into thinking the atmosphere started lower is because the air pressure/density at the boundary is now equal to zero, so the immediate effects, such as drag, are less noticeable. Previously the atmosphere abruptly stopped when P=Po/1000000, so it was more obvious when the boundary was crossed. Now you have to descend all the way to 68,259 m before the pressure reaches that value. Interestingly, that is also the altitude at which I noticed the barometer starts to read "IN VACUUM". Looks like the barometer may include code that is a relic of the old model. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 14:20, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:One of the reasons why you might have been fooled into thinking the atmosphere started lower is because the air pressure/density at the boundary is now equal to zero, so the immediate effects, such as drag, are less noticeable. Previously the atmosphere abruptly stopped when P=Po/1000000, so it was more obvious when the boundary was crossed. Now you have to descend all the way to 68,259 m before the pressure reaches that value. Interestingly, that is also the altitude at which I noticed the barometer starts to read "IN VACUUM". Looks like the barometer may include code that is a relic of the old model. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 14:20, 18 May 2015 (UTC)</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">::I actually hadn't bothered reading the pressure sensor as I wasn't aware of the changes (and I hadn't been able to play KSP yet). But afaik the sensor simply says “IN VACUUM” at a certain pressure (which is also what the article says but at 10⁻⁵ atm not 10⁻⁶ atm). — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 21:09, 18 May 2015 (UTC)</ins></div></td></tr>
</table>XZisehttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62824&oldid=prevOhioBob: /* Scale heights */2015-05-18T16:51:32Z<p><span dir="auto"><span class="autocomment">Scale heights</span></span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like <nowiki>{{Body data/pressure approx|</nowiki>''body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like <nowiki>{{Body data/pressure approx|</nowiki>''body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>:One of the reasons why you might have been fooled into thinking the atmosphere started lower is because the air pressure/density at the boundary is now equal to zero, so the immediate effects, such as drag, are less noticeable. Previously the atmosphere abruptly stopped when P=Po/1000000, so it was more obvious when the boundary was crossed. Now you have to descend all the way to 68,259 m before the pressure reaches that value. Interestingly, that is also the altitude at which I noticed <del class="diffchange diffchange-inline">that </del>the barometer starts to read "IN VACUUM". Looks like the barometer may include code that is a relic of the old model. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 14:20, 18 May 2015 (UTC)</div></td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>:One of the reasons why you might have been fooled into thinking the atmosphere started lower is because the air pressure/density at the boundary is now equal to zero, so the immediate effects, such as drag, are less noticeable. Previously the atmosphere abruptly stopped when P=Po/1000000, so it was more obvious when the boundary was crossed. Now you have to descend all the way to 68,259 m before the pressure reaches that value. Interestingly, that is also the altitude at which I noticed the barometer starts to read "IN VACUUM". Looks like the barometer may include code that is a relic of the old model. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 14:20, 18 May 2015 (UTC)</div></td></tr>
</table>OhioBobhttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62823&oldid=prevOhioBob: /* Scale heights */2015-05-18T15:20:09Z<p><span dir="auto"><span class="autocomment">Scale heights</span></span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::I'm going to try to make some time in-game to do some practical experimentation around the atmospheric boundaries, to confirm accuracy of the numbers, but my feeling right now is that the new static numbers probably are correct.  I think they are accurate, just the scientist and engineer in me wants to personally verify them.  Based on normal launching from Kerbin and re-entering, it does seem like it's exactly 70,000m when the game changes mode from space to atmospheric (the change in music and time warp bar).  For now, I feel reasonably confident that the numbers are good for at least saying to players that "above this height you're ok, below it you're going to be aerobraking".</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::I'm going to try to make some time in-game to do some practical experimentation around the atmospheric boundaries, to confirm accuracy of the numbers, but my feeling right now is that the new static numbers probably are correct.  I think they are accurate, just the scientist and engineer in me wants to personally verify them.  Based on normal launching from Kerbin and re-entering, it does seem like it's exactly 70,000m when the game changes mode from space to atmospheric (the change in music and time warp bar).  For now, I feel reasonably confident that the numbers are good for at least saying to players that "above this height you're ok, below it you're going to be aerobraking".</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::--[[User:Murph|Murph]] ([[User talk:Murph|talk]]) 23:34, 17 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::--[[User:Murph|Murph]] ([[User talk:Murph|talk]]) 23:34, 17 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::I recently exchanged private correspondence with an insider who worked with Squad to develop the current atmospheric model. He gave me a copy of the config file, though I believe he intended it to be for my eyes only. I don't believe I have a right to share or distribute the file, though I feel comfortable discussing its contents. The file does not appear to be anywhere in the KSP folder, so you are probably correct that it is embedded in the .assests files. I can confirm that the atmosphere heights that I posted previously are indeed a fact. Atmospheric pressure is evaluated using a floatCurve. Each pair of points on the curve are connected by a spline with its own equation. The pressure curve for Kerbin contains 18 splines and 18 equations, though most other curves are simpler than that. Evaluating the curves to find an exact solution is way more mathematically involved then I think is appropriate to include in the Wiki articles. I was thinking about simply providing a table that gives temperature and pressure at regular altitude increments. This is something I can compute from the floatCurve data. Something else I can do is generate graphs of temperature and pressure vs. altitude (in fact, I've already done this). Using P=Po*EXP(-z/H) with a constant scale height provides only a ballpark solution. The scale heights I computed are probably about as close as we can get, but there's going to be significant error in some places. I'm sure I can derive a single equation that will be much closer, but it will still be an approximation. The equation would be in the form P=EXP(f(z)), where f(z) is a polynomial. I'm planning to rewrite sections of the Wiki articles to bring them up to date with the v1.0 changes. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 04:48, 18 May 2015 (UTC)</div></td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::I recently exchanged private correspondence with an insider who worked with Squad to <ins class="diffchange diffchange-inline">help </ins>develop the current atmospheric model. He gave me a copy of the config file, though I believe he intended it to be for my eyes only. I don't believe I have a right to share or distribute the file, though I feel comfortable discussing its contents. The file does not appear to be anywhere in the KSP folder, so you are probably correct that it is embedded in the .assests files. I can confirm that the atmosphere heights that I posted previously are indeed a fact. Atmospheric pressure is evaluated using a floatCurve. Each pair of points on the curve are connected by a spline with its own equation. The pressure curve for Kerbin contains 18 splines and 18 equations, though most other curves are simpler than that. Evaluating the curves to find an exact solution is way more mathematically involved then I think is appropriate to include in the Wiki articles. I was thinking about simply providing a table that gives temperature and pressure at regular altitude increments. This is something I can compute from the floatCurve data. Something else I can do is generate graphs of temperature and pressure vs. altitude (in fact, I've already done this). Using P=Po*EXP(-z/H) with a constant scale height provides only a ballpark solution. The scale heights I computed are probably about as close as we can get, but there's going to be significant error in some places. I'm sure I can derive a single equation that will be much closer, but it will still be an approximation. The equation would be in the form P=EXP(f(z)), where f(z) is a polynomial. I'm planning to rewrite sections of the Wiki articles to bring them up to date with the v1.0 changes. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 04:48, 18 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example equation that can be used to estimate pressure on Kerbin... P = EXP(9.8837225E-24*Z^5-2.3533019E-18*Z^4+1.7819528E-13*Z^3-5.0065555E-09*Z^2-0.00013849112*Z+11.5260885), where P is in Pa and Z is in meters. It's not pretty but it gets the job done. The equation approximates atmospheric pressure to within 1% up to about 29 km, and to within 2% to 62.3 km. Things breakdown above 62.3 km because that's were Squad begins to force the curve to go to P=0 at 70 km. I can derive similar equations for the other planets as well. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:16, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example equation that can be used to estimate pressure on Kerbin... P = EXP(9.8837225E-24*Z^5-2.3533019E-18*Z^4+1.7819528E-13*Z^3-5.0065555E-09*Z^2-0.00013849112*Z+11.5260885), where P is in Pa and Z is in meters. It's not pretty but it gets the job done. The equation approximates atmospheric pressure to within 1% up to about 29 km, and to within 2% to 62.3 km. Things breakdown above 62.3 km because that's were Squad begins to force the curve to go to P=0 at 70 km. I can derive similar equations for the other planets as well. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:16, 18 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example of one of the graphs I created... http://www.braeunig.us/pics/KSP/Kerbin_Atmosphere_T&P.png. I've made one for each planet and I'm thinking about using them in the Wiki articles. The graphs depict exactly the floatCurves, though I've plotted pressure on a logarithmic scale. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:36, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example of one of the graphs I created... http://www.braeunig.us/pics/KSP/Kerbin_Atmosphere_T&P.png. I've made one for each planet and I'm thinking about using them in the Wiki articles. The graphs depict exactly the floatCurves, though I've plotted pressure on a logarithmic scale. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:36, 18 May 2015 (UTC)</div></td></tr>
</table>OhioBobhttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62819&oldid=prevOhioBob: /* Scale heights */2015-05-18T14:20:43Z<p><span dir="auto"><span class="autocomment">Scale heights</span></span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like <nowiki>{{Body data/pressure approx|</nowiki>''body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like <nowiki>{{Body data/pressure approx|</nowiki>''body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">:One of the reasons why you might have been fooled into thinking the atmosphere started lower is because the air pressure/density at the boundary is now equal to zero, so the immediate effects, such as drag, are less noticeable. Previously the atmosphere abruptly stopped when P=Po/1000000, so it was more obvious when the boundary was crossed. Now you have to descend all the way to 68,259 m before the pressure reaches that value. Interestingly, that is also the altitude at which I noticed that the barometer starts to read "IN VACUUM". Looks like the barometer may include code that is a relic of the old model. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 14:20, 18 May 2015 (UTC)</ins></div></td></tr>
</table>OhioBobhttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62811&oldid=prevXZise: /* Scale heights */2015-05-18T09:16:29Z<p><span dir="auto"><span class="autocomment">Scale heights</span></span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Thank you for your information and if you actually got internal information then I have no objections (although I find it dull that they used hard coded exact values). I was pretty sure that the music started below 70&nbsp;km, but it seems that my mind was playing tricks on me.</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>Thank you for your information and if you actually got internal information then I have no objections (although I find it dull that they used hard coded exact values). I was pretty sure that the music started below 70&nbsp;km, but it seems that my mind was playing tricks on me.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like {{<del class="diffchange diffchange-inline">''</del>Body data/pressure approx|body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like <ins class="diffchange diffchange-inline"><nowiki></ins>{{Body data/pressure approx|<ins class="diffchange diffchange-inline"></nowiki>''</ins>body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</div></td></tr>
</table>XZisehttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62810&oldid=prevXZise: /* Scale heights */2015-05-18T09:15:17Z<p><span dir="auto"><span class="autocomment">Scale heights</span></span></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example equation that can be used to estimate pressure on Kerbin... P = EXP(9.8837225E-24*Z^5-2.3533019E-18*Z^4+1.7819528E-13*Z^3-5.0065555E-09*Z^2-0.00013849112*Z+11.5260885), where P is in Pa and Z is in meters. It's not pretty but it gets the job done. The equation approximates atmospheric pressure to within 1% up to about 29 km, and to within 2% to 62.3 km. Things breakdown above 62.3 km because that's were Squad begins to force the curve to go to P=0 at 70 km. I can derive similar equations for the other planets as well. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:16, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example equation that can be used to estimate pressure on Kerbin... P = EXP(9.8837225E-24*Z^5-2.3533019E-18*Z^4+1.7819528E-13*Z^3-5.0065555E-09*Z^2-0.00013849112*Z+11.5260885), where P is in Pa and Z is in meters. It's not pretty but it gets the job done. The equation approximates atmospheric pressure to within 1% up to about 29 km, and to within 2% to 62.3 km. Things breakdown above 62.3 km because that's were Squad begins to force the curve to go to P=0 at 70 km. I can derive similar equations for the other planets as well. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:16, 18 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example of one of the graphs I created... http://www.braeunig.us/pics/KSP/Kerbin_Atmosphere_T&P.png. I've made one for each planet and I'm thinking about using them in the Wiki articles. The graphs depict exactly the floatCurves, though I've plotted pressure on a logarithmic scale. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:36, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example of one of the graphs I created... http://www.braeunig.us/pics/KSP/Kerbin_Atmosphere_T&P.png. I've made one for each planet and I'm thinking about using them in the Wiki articles. The graphs depict exactly the floatCurves, though I've plotted pressure on a logarithmic scale. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:36, 18 May 2015 (UTC)</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">{{Outdent|:::::::::::}}</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Thank you for your information and if you actually got internal information then I have no objections (although I find it dull that they used hard coded exact values). I was pretty sure that the music started below 70&nbsp;km, but it seems that my mind was playing tricks on me.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Now regarding your approximation: I appreciate the work you've done there and in theory we could have the formula in something like {{Tl|body data}} so you'd only do something like {{''Body data/pressure approx|body|height''}} and it would get you the approximated value. I believe that calculating it with the more complex approximation isn't that much more complicated to the server than with the current approximation (but I might be wrong). I'm not so good at that math so I can only guess but would it maybe possible to have an if condition that returns two different approximations depending on the height? — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 09:15, 18 May 2015 (UTC)</ins></div></td></tr>
</table>XZisehttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62801&oldid=prevOhioBob: /* Scale heights */2015-05-18T05:36:59Z<p><span dir="auto"><span class="autocomment">Scale heights</span></span></p>
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<td colspan='2' style="background-color: white; color:black; text-align: center;">Revision as of 05:36, 18 May 2015</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l65" >Line 65:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::I recently exchanged private correspondence with an insider who worked with Squad to develop the current atmospheric model. He gave me a copy of the config file, though I believe he intended it to be for my eyes only. I don't believe I have a right to share or distribute the file, though I feel comfortable discussing its contents. The file does not appear to be anywhere in the KSP folder, so you are probably correct that it is embedded in the .assests files. I can confirm that the atmosphere heights that I posted previously are indeed a fact. Atmospheric pressure is evaluated using a floatCurve. Each pair of points on the curve are connected by a spline with its own equation. The pressure curve for Kerbin contains 18 splines and 18 equations, though most other curves are simpler than that. Evaluating the curves to find an exact solution is way more mathematically involved then I think is appropriate to include in the Wiki articles. I was thinking about simply providing a table that gives temperature and pressure at regular altitude increments. This is something I can compute from the floatCurve data. Something else I can do is generate graphs of temperature and pressure vs. altitude (in fact, I've already done this). Using P=Po*EXP(-z/H) with a constant scale height provides only a ballpark solution. The scale heights I computed are probably about as close as we can get, but there's going to be significant error in some places. I'm sure I can derive a single equation that will be much closer, but it will still be an approximation. The equation would be in the form P=EXP(f(z)), where f(z) is a polynomial. I'm planning to rewrite sections of the Wiki articles to bring them up to date with the v1.0 changes. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 04:48, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::I recently exchanged private correspondence with an insider who worked with Squad to develop the current atmospheric model. He gave me a copy of the config file, though I believe he intended it to be for my eyes only. I don't believe I have a right to share or distribute the file, though I feel comfortable discussing its contents. The file does not appear to be anywhere in the KSP folder, so you are probably correct that it is embedded in the .assests files. I can confirm that the atmosphere heights that I posted previously are indeed a fact. Atmospheric pressure is evaluated using a floatCurve. Each pair of points on the curve are connected by a spline with its own equation. The pressure curve for Kerbin contains 18 splines and 18 equations, though most other curves are simpler than that. Evaluating the curves to find an exact solution is way more mathematically involved then I think is appropriate to include in the Wiki articles. I was thinking about simply providing a table that gives temperature and pressure at regular altitude increments. This is something I can compute from the floatCurve data. Something else I can do is generate graphs of temperature and pressure vs. altitude (in fact, I've already done this). Using P=Po*EXP(-z/H) with a constant scale height provides only a ballpark solution. The scale heights I computed are probably about as close as we can get, but there's going to be significant error in some places. I'm sure I can derive a single equation that will be much closer, but it will still be an approximation. The equation would be in the form P=EXP(f(z)), where f(z) is a polynomial. I'm planning to rewrite sections of the Wiki articles to bring them up to date with the v1.0 changes. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 04:48, 18 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example equation that can be used to estimate pressure on Kerbin... P = EXP(9.8837225E-24*Z^5-2.3533019E-18*Z^4+1.7819528E-13*Z^3-5.0065555E-09*Z^2-0.00013849112*Z+11.5260885), where P is in Pa and Z is in meters. It's not pretty but it gets the job done. The equation approximates atmospheric pressure to within 1% up to about 29 km, and to within 2% to 62.3 km. Things breakdown above 62.3 km because that's were Squad begins to force the curve to go to P=0 at 70 km. I can derive similar equations for the other planets as well. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:16, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::Here's an example equation that can be used to estimate pressure on Kerbin... P = EXP(9.8837225E-24*Z^5-2.3533019E-18*Z^4+1.7819528E-13*Z^3-5.0065555E-09*Z^2-0.00013849112*Z+11.5260885), where P is in Pa and Z is in meters. It's not pretty but it gets the job done. The equation approximates atmospheric pressure to within 1% up to about 29 km, and to within 2% to 62.3 km. Things breakdown above 62.3 km because that's were Squad begins to force the curve to go to P=0 at 70 km. I can derive similar equations for the other planets as well. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:16, 18 May 2015 (UTC)</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">:::::::::::Here's an example of one of the graphs I created... http://www.braeunig.us/pics/KSP/Kerbin_Atmosphere_T&P.png. I've made one for each planet and I'm thinking about using them in the Wiki articles. The graphs depict exactly the floatCurves, though I've plotted pressure on a logarithmic scale. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:36, 18 May 2015 (UTC)</ins></div></td></tr>
</table>OhioBobhttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62800&oldid=prevOhioBob: /* Scale heights */2015-05-18T05:16:18Z<p><span dir="auto"><span class="autocomment">Scale heights</span></span></p>
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<td colspan='2' style="background-color: white; color:black; text-align: center;">Revision as of 05:16, 18 May 2015</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l64" >Line 64:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::--[[User:Murph|Murph]] ([[User talk:Murph|talk]]) 23:34, 17 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::--[[User:Murph|Murph]] ([[User talk:Murph|talk]]) 23:34, 17 May 2015 (UTC)</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::I recently exchanged private correspondence with an insider who worked with Squad to develop the current atmospheric model. He gave me a copy of the config file, though I believe he intended it to be for my eyes only. I don't believe I have a right to share or distribute the file, though I feel comfortable discussing its contents. The file does not appear to be anywhere in the KSP folder, so you are probably correct that it is embedded in the .assests files. I can confirm that the atmosphere heights that I posted previously are indeed a fact. Atmospheric pressure is evaluated using a floatCurve. Each pair of points on the curve are connected by a spline with its own equation. The pressure curve for Kerbin contains 18 splines and 18 equations, though most other curves are simpler than that. Evaluating the curves to find an exact solution is way more mathematically involved then I think is appropriate to include in the Wiki articles. I was thinking about simply providing a table that gives temperature and pressure at regular altitude increments. This is something I can compute from the floatCurve data. Something else I can do is generate graphs of temperature and pressure vs. altitude (in fact, I've already done this). Using P=Po*EXP(-z/H) with a constant scale height provides only a ballpark solution. The scale heights I computed are probably about as close as we can get, but there's going to be significant error in some places. I'm sure I can derive a single equation that will be much closer, but it will still be an approximation. The equation would be in the form P=EXP(f(z)), where f(z) is a polynomial. I'm planning to rewrite sections of the Wiki articles to bring them up to date with the v1.0 changes. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 04:48, 18 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::::I recently exchanged private correspondence with an insider who worked with Squad to develop the current atmospheric model. He gave me a copy of the config file, though I believe he intended it to be for my eyes only. I don't believe I have a right to share or distribute the file, though I feel comfortable discussing its contents. The file does not appear to be anywhere in the KSP folder, so you are probably correct that it is embedded in the .assests files. I can confirm that the atmosphere heights that I posted previously are indeed a fact. Atmospheric pressure is evaluated using a floatCurve. Each pair of points on the curve are connected by a spline with its own equation. The pressure curve for Kerbin contains 18 splines and 18 equations, though most other curves are simpler than that. Evaluating the curves to find an exact solution is way more mathematically involved then I think is appropriate to include in the Wiki articles. I was thinking about simply providing a table that gives temperature and pressure at regular altitude increments. This is something I can compute from the floatCurve data. Something else I can do is generate graphs of temperature and pressure vs. altitude (in fact, I've already done this). Using P=Po*EXP(-z/H) with a constant scale height provides only a ballpark solution. The scale heights I computed are probably about as close as we can get, but there's going to be significant error in some places. I'm sure I can derive a single equation that will be much closer, but it will still be an approximation. The equation would be in the form P=EXP(f(z)), where f(z) is a polynomial. I'm planning to rewrite sections of the Wiki articles to bring them up to date with the v1.0 changes. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 04:48, 18 May 2015 (UTC)</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">:::::::::::Here's an example equation that can be used to estimate pressure on Kerbin... P = EXP(9.8837225E-24*Z^5-2.3533019E-18*Z^4+1.7819528E-13*Z^3-5.0065555E-09*Z^2-0.00013849112*Z+11.5260885), where P is in Pa and Z is in meters. It's not pretty but it gets the job done. The equation approximates atmospheric pressure to within 1% up to about 29 km, and to within 2% to 62.3 km. Things breakdown above 62.3 km because that's were Squad begins to force the curve to go to P=0 at 70 km. I can derive similar equations for the other planets as well. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 05:16, 18 May 2015 (UTC)</ins></div></td></tr>
</table>OhioBobhttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62799&oldid=prevOhioBob at 04:48, 18 May 20152015-05-18T04:48:30Z<p></p>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::I'm going to try to make some time in-game to do some practical experimentation around the atmospheric boundaries, to confirm accuracy of the numbers, but my feeling right now is that the new static numbers probably are correct.  I think they are accurate, just the scientist and engineer in me wants to personally verify them.  Based on normal launching from Kerbin and re-entering, it does seem like it's exactly 70,000m when the game changes mode from space to atmospheric (the change in music and time warp bar).  For now, I feel reasonably confident that the numbers are good for at least saying to players that "above this height you're ok, below it you're going to be aerobraking".</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::I'm going to try to make some time in-game to do some practical experimentation around the atmospheric boundaries, to confirm accuracy of the numbers, but my feeling right now is that the new static numbers probably are correct.  I think they are accurate, just the scientist and engineer in me wants to personally verify them.  Based on normal launching from Kerbin and re-entering, it does seem like it's exactly 70,000m when the game changes mode from space to atmospheric (the change in music and time warp bar).  For now, I feel reasonably confident that the numbers are good for at least saying to players that "above this height you're ok, below it you're going to be aerobraking".</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::--[[User:Murph|Murph]] ([[User talk:Murph|talk]]) 23:34, 17 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>::::::::::--[[User:Murph|Murph]] ([[User talk:Murph|talk]]) 23:34, 17 May 2015 (UTC)</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">:::::::::::I recently exchanged private correspondence with an insider who worked with Squad to develop the current atmospheric model. He gave me a copy of the config file, though I believe he intended it to be for my eyes only. I don't believe I have a right to share or distribute the file, though I feel comfortable discussing its contents. The file does not appear to be anywhere in the KSP folder, so you are probably correct that it is embedded in the .assests files. I can confirm that the atmosphere heights that I posted previously are indeed a fact. Atmospheric pressure is evaluated using a floatCurve. Each pair of points on the curve are connected by a spline with its own equation. The pressure curve for Kerbin contains 18 splines and 18 equations, though most other curves are simpler than that. Evaluating the curves to find an exact solution is way more mathematically involved then I think is appropriate to include in the Wiki articles. I was thinking about simply providing a table that gives temperature and pressure at regular altitude increments. This is something I can compute from the floatCurve data. Something else I can do is generate graphs of temperature and pressure vs. altitude (in fact, I've already done this). Using P=Po*EXP(-z/H) with a constant scale height provides only a ballpark solution. The scale heights I computed are probably about as close as we can get, but there's going to be significant error in some places. I'm sure I can derive a single equation that will be much closer, but it will still be an approximation. The equation would be in the form P=EXP(f(z)), where f(z) is a polynomial. I'm planning to rewrite sections of the Wiki articles to bring them up to date with the v1.0 changes. [[User:OhioBob|OhioBob]] ([[User talk:OhioBob|talk]]) 04:48, 18 May 2015 (UTC)</ins></div></td></tr>
</table>OhioBobhttps://wiki.kerbalspaceprogram.com/index.php?title=User_talk:OhioBob&diff=62798&oldid=prevMurph: /* Scale heights */ reply2015-05-17T23:34:24Z<p><span dir="auto"><span class="autocomment">Scale heights: </span> reply</span></p>
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<td colspan='2' style="background-color: white; color:black; text-align: center;">Revision as of 23:34, 17 May 2015</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::Well my comment was more a response to Murph but nevermind. I'm interested in the configuration file however. I recently looked through the files and couldn't really find one (although that was 0.90 and I was more for a quest after all the properties of a planet and not just the atmosphere). — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 19:20, 17 May 2015 (UTC)</div></td><td class='diff-marker'> </td><td style="background-color: #f9f9f9; color: #333333; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #e6e6e6; vertical-align: top; white-space: pre-wrap;"><div>:::::::::Well my comment was more a response to Murph but nevermind. I'm interested in the configuration file however. I recently looked through the files and couldn't really find one (although that was 0.90 and I was more for a quest after all the properties of a planet and not just the atmosphere). — [[User:XZise|xZise]] <small>&#91;[[User talk:XZise|talk]]&#93;</small> 19:20, 17 May 2015 (UTC)</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">::::::::::It would be great if we could get our hands on the configuration files themselves, but I think they must be embedded in the ".assets" files, as I also can't find anything in GameData which relates to it.  I don't know how to open those files and examine the contents, although will poke around and see what readable text there is inside them.  I'll leave it up to you if you want to go to the effort of adding hidden tracking categories.  I think I did get all of the main usage of "scale height" for atmospheric height, just wanted to flag that I couldn't be 100% confident due to the wide transclusion.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">::::::::::As for {{tl|Body data/alt at pressure}}, hopefully OhioBob's changes to scale height should make that at least approximately correct, but it sounds like we'll never be able to get it 100% correct without getting our hands on Squad's new parameters, and the maths used to translate them into the model.  Approximation is better than nothing, as long as we know it's an approximation, and it's not wildly out for the majority of cases.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">::::::::::I'm going to try to make some time in-game to do some practical experimentation around the atmospheric boundaries, to confirm accuracy of the numbers, but my feeling right now is that the new static numbers probably are correct.  I think they are accurate, just the scientist and engineer in me wants to personally verify them.  Based on normal launching from Kerbin and re-entering, it does seem like it's exactly 70,000m when the game changes mode from space to atmospheric (the change in music and time warp bar).  For now, I feel reasonably confident that the numbers are good for at least saying to players that "above this height you're ok, below it you're going to be aerobraking".</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color:black; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">::::::::::--[[User:Murph|Murph]] ([[User talk:Murph|talk]]) 23:34, 17 May 2015 (UTC)</ins></div></td></tr>
</table>Murph