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MaskRider
July 21st, 2010, 07:14
Guys, I need some help.

As the next step in my current Marianas project, I have been devoting time the last few days to rebuilding the islands between Saipan and Chi-Chi Jima (Not including Chi-Chi Jima). Rebuilding them so that their water/land masks fit with JP's very nice lod9 mesh donated to the project. It covers from Guam thru the Hata Jima island group.

I am using G2K(4) and FSSC as usual.

I am wondering whether or not there is an alternative to A16 flat areas that I can use for some of the more troublesome islands and the mesh underlying their locations.

Problem is that all of these islands are very active volcanically so on any given radar mapping run the SRTM/SWBD data may and does treat volcanic plumes as elevated parts of the island which in reality should be zero altitude water.

I was hoping that the "altitude meters" setting in the LWM properties tab would allow me to use a water mask as a flatten. I tried setting the value to "0" (changing it from its default value of "-9999") but it doesn't seem to have any effect. Using G2K(4) is there an "Altitude meters" value that will flatten the water under the LWM (water) poly to "0"? Or am I barking up the wrong tree?

What I was hoping of course is that after making the standard island with shore poly for the island, I could turn around, save the project with another name and convert the same poly construction line into a flattening water mask poly (after adding lines that enclose a body of water off shore).

Is this possible? Will, G2K(4) do this? If so what value does that "altitude meters" under the LWM tab need to be?

If not, is there a program that will do this- such as SBuilder? Maybe one that will allow me to import a bgl created in G2K(4) and use it as a map for a flatten poly?

Any guidance would be most welcome!

Thanks!
MR

MaskRider
July 21st, 2010, 07:22
Of course I guess I could edit the image of JP's mesh bgl- zeroing out the offending lods(?), tiles(?) and then recompile the resulting RAW (?) file as a new mesh bgl? Not sure how to do this. But it seems that I have probably been told how at some time in the past- or the idea wouldn't have occurred to me! :d

Just thinkin. Got to get this niggling problem solved.

rhumbaflappy
July 21st, 2010, 09:09
Hi MR.

CFS2 LWMs have no flatten ability.

Sander's cfs2AutoCoast has a menu option to import an SBuilder SBX file and convert it to an Area16n flatten bgl. But, there is a problem in that SBuilder will not accept an import of a CFS2 LWM bgl. :(

The work-around is to compile a copy of your LWM in Ground2k as flight simulator ( not as cfs2 ). Make sure the polys are zero altitude for sea-level. This bgl can be imported to SBuilder, and exported as an SBX file.

That SBX file can then be converted to an A16n flatten bgl by Sander's program.

We found there was no frame-rate difference between A16n flattens and FS2002 LWM water flattens in Fs2002, so I wouldn't worry about frame-rate issues.

Dick

MaskRider
July 21st, 2010, 09:40
Thanks Dick!

Doesn't sound any more Rube Goldberg than many other scenery building routines I use! :d

I'll give it a go!

FMI: When you say to "make sure the polys are zero altitude for sea-level" you are refering to the "altitude meters" setting in the G2K(4) LWM properties tab I mentioned above?

I am excited to see how this works!

MR

rhumbaflappy
July 21st, 2010, 09:54
Hi MR.

altitude meters... yes. Set it to zero.

You have the option in SBuilder to delete polys that you don't need flattened ( areas of solid ocean mesh that don't need flattening applied ). That will save some frame-rates.

Dick

MaskRider
July 21st, 2010, 10:33
Thanks, Dick.

Preparing to run my first poly thru the G2k -> SBuilder -> AutoCoast routine.

MaskRider
July 21st, 2010, 11:49
Well, I easily got the bgl run thru the process.

Unfortunately, the flatten cuts inland from the coast, too- instead of just out from the coast as it was drawn. Making cliffs out of what should be steeply sloped hills running into the sea. Not sure why this would be.

Indeed it seems to be a tad offset to the south east? Because there is no cutting in to speak of on the south side of the island. I was expecting to see the flatten start at the beach line and go out to sea. The LWM poly was a straight conversion from the shoreline poly.

Does it have something to do with it being changed to an FS style poly?

Would it make a difference that the shoreline was created as a cfs2 poly and then that project was saved as a FS project to make the LWM -> A16 conversion?

Guess I can try that angle and see if anything changes.

MaskRider
July 22nd, 2010, 18:31
Hiy Dick,

Asuncion Island was the next island up the Mariana chain that had a glaring need for some mesh massaging. A volcanic plume created a significantly and errantly elevated areas of H2O off to the SE of the island. Yes, I could have just gone with the "flow" and turned it into islands- but it would have looked dumb. So, I tried the water mask conversion flatten routine that you outline above.

Keeping in mind from the first go round that the resulting A16 flatten goes significantly "inland" from its actually poly boundary- as drawn in G2K(4)- I simply gave it a nice fire break between the watermask-flatten poly and the actual shore line that I wanted. It worked out fine.

Here are a few screenies to help explain how I worked thru it in case any one is interested. Not breaking any new ground here:

To help deal with the discrepancy between your LOD8 mesh/masks and JP's LOD9 mesh- in that the water mask resulting from the one doesn't always coincide with that of the other- I have been using a multi-layerd project map consisting of:

Background layer: the original shp file export image.
Layer2: a screenie of same as viewed in the G2K(4) layout window- with LOD13 grid showing.
Layer3: on top, a screenie of JP's mesh at the same location as viewed in LWMViewer- also with the LOD13 grid showing.

I first re-size layer two to fit the background layer. Then it is just a matter of lining up the grid lines in layer 2 and layer 3 to get everything lined up properly.

When making the land poly I follow the shp image outline when it is outside of the mesh and the mesh when it is outside of the shp file outline. It works well and makes a very nice tight fit shoreline to mesh.

A few screenies: Layer1, Layer2, Layer3, and the actual project map.
13395133941339613393

The poly in red in screenie 4 is the one I run thru the conversion routine.

Anyway, Dick, I just wanted you to know that the routine you clued me into is really working out nicely on this project. Thanks again!

Chris