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Guest berlin4321

Sloping Runways (Problem Solved with LWMPoly3?)

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I may have solved my problems with creating a sloping runway.I have been trying to replicate an airfield with a substantial upslope from west to east. I could not use a regular runway, because it forces the terrain to be flat. This meant that I would either have the runway above ground level on the west side or below ground level on the east side, or both.Instead, I designed an airfield using FSSC and removed the flatten and replaced the runways with taxiways. This is not as horrible as it seems because the real runways did not have a lot of texture to them.The trouble was that the terrain was not perfectly flat and I kept seeing "tears" in the runways. I solved the problem somewhat by increasing the number of runway points and even using multiple taxiways to create a single runway. However, I was never entirely able to eliminate the tears.After reading many posts on this forum, it finally dawned on me that I might be able to use the new LWMPoly3 function to create an area with some slope, since that function allows you to designate an altitude for the LWM points. I tried it and it works! In four areas, I created a rectangle with a slight upslope that is slightly above the ground level of the regular terrain.Now the taxiways lay flat, even the ones with minimal points.Here is the source code:include TDFMacros.incinclude TDFHeaders.incBGLHeader 17, 13, 148, 144, LWMHeader, TerrainHeaderStartLWMHeader label wordLWMFileHeader 300h, LWMIndexStart, LWMStart, LWMEndLWMStart label word datamark_0 label word LWMDataAreaDrawPolygons 1, 3, 1, 21, 3LWMPoly3 4, 0, 1, 18, 0, 30, 0LWMPoint3 075, 255, 001LWMPoint3 075, 160, 001LWMPoint3 255, 160, 255LWMPoint3 255, 255, 255 LWMDataAreaDrawPolygons 1, 3, 1, 22, 3LWMPoly3 4, 0, 1, 30, 0, 42, 0LWMPoint3 000, 160, 001LWMPoint3 245, 160, 255LWMPoint3 245, 255, 255LWMPoint3 000, 255, 001 LWMDataAreaDrawPolygons 1, 3, 1, 21, 4LWMPoly3 4, 0, 1, 18, 0, 30, 0LWMPoint3 075, 000, 001LWMPoint3 255, 000, 255LWMPoint3 255, 230, 255LWMPoint3 075, 230, 001 LWMDataAreaDrawPolygons 1, 3, 1, 22, 4LWMPoly3 4, 0, 1, 30, 0, 42, 0LWMPoint3 000, 000, 001LWMPoint3 245, 000, 255LWMPoint3 245, 230, 255LWMPoint3 000, 230, 001 datamark_1 label word Cellv_694_213 EQU LWMCellID 0, 0, 3, 694, 213LWMIndexStart label wordLWMIndexHeader 1, LWMIndexDataLWMIndexData label wordLWMIndexEntry Cellv_694_213, LWMStart, datamark_0, datamark_1 LWMEnd label wordThe resulting bgl creates a flat area on North Tinian island. (Go to West Tinian Airfield and fly straight north.) This might not show up perfectly on an umodified version of the island (I have remeshed and moved my island slightly). But it should show up well enough to demonstrate what I have done.Is this a good solution, or am I trifling with powers that are beyond my comprehension?

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When I discovered the height info in LWMPoly3 I suspected that this could be used for sloping runways. There is 1 reason, why I haven't used it myself yet: the xml runway is flat. The runway polygon will float over the terrain, so your airplane will dive into the runway (or terrain may grow out of the runway).The solution would of course be not to use xml runways, but instead custom bitmaps. But since visual runway info and AFD info are linked now, this is not really the way to go, IMHO.Cheers, Christian

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Christian,You are right. This is not a solution for everyone. My airport is not an "active" airport, so I am not losing anything. And, I am not aware of any way to add new airports to the list of active airports.And I am sure that the AI aircraft are helped by the assumption that the runway is level. So, even if I were able to convince some AI aircraft to fly into my airport, I could expect some spectacular crashes.In my case, the upslope runway adds a sense of realism to the takeoff since FS9 aircraft seem to accelerate more slowly on an upslope. In my case, the aircraft has not quite reached flying speed at the end of the runway. Which appears to be exactly how it was it real life and which explains why they paved part of the "drop off" at the end of the upslope.I even hate having to use the flatten command because it was fun to "bounce along" on take off and to be able to see all the different levels on the airport. (Almost no airport is perfectly flat.) But there seems to be no other way to take advantage of the hi-resolution mode.Phil

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May be one day even MS Flight sim will have Ground undulation and sloping Airfields like these from SFSPC 4.1.41.jpg2.jpg3.jpg4.jpgCheers

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