• Which the release of FS2020 we see an explosition of activity on the forun and of course we are very happy to see this. But having all questions about FS2020 in one forum becomes a bit messy. So therefore we would like to ask you all to use the following guidelines when posting your questions:

    • Tag FS2020 specific questions with the MSFS2020 tag.
    • Questions about making 3D assets can be posted in the 3D asset design forum. Either post them in the subforum of the modelling tool you use or in the general forum if they are general.
    • Questions about aircraft design can be posted in the Aircraft design forum
    • Questions about airport design can be posted in the FS2020 airport design forum. Once airport development tools have been updated for FS2020 you can post tool speciifc questions in the subforums of those tools as well of course.
    • Questions about terrain design can be posted in the FS2020 terrain design forum.
    • Questions about SimConnect can be posted in the SimConnect forum.

    Any other question that is not specific to an aspect of development or tool can be posted in the General chat forum.

    By following these guidelines we make sure that the forums remain easy to read for everybody and also that the right people can find your post to answer it.

FSX How do I Cover a Portion of a Photo Real Image

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845
Hi Gary,

I assume I did this correctly and here are my results of the ArcGIS image bgl in FSX:


KBHM AchGIS.jpg



The runways and the taxiways all line up perfectly. But noticed the runways are shorter than what's shown in the image. That's how long they were back in the 1970s and 1980s. The National Guard on the north side is totally different than what it was in 1970. It was a housing project then, but the airport bought out the property.

Ken.
 

Deano1973

Resource contributor
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Hi Ken,

You can use Airport Design Editor to shorten the length of the runways - just select the runway in the editor, right click, and it will give a list of options, one of which is called "Properties" or similar. In there will be runway lengths, widths, styles etc, so you can edit until the runway fits perfectly.
 
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845
Hi Ken,

You can use Airport Design Editor to shorten the length of the runways - just select the runway in the editor, right click, and it will give a list of options, one of which is called "Properties" or similar. In there will be runway lengths, widths, styles etc, so you can edit until the runway fits perfectly.


Hi Deano1973,

Yes, that's correct. If you look closely at the photo above, you can see that's what I've done. This airport has gone through 3 or 4 changes and that's why I wanted an image from that time period so that I would have everything as it existed. I grew up living around that airport and seen a lot of changes. Noticed in the photo that I did not draw certain taxiways because they did not exist then. I had to use the original images to determine that because it's been so long ago. Also notice how the National Guard apron has been twisted and repaved since the 1970s. It's on the north side of the field. It's not only things regarding the runways and taxiways, but it's also the ramp, terminals buildings, and the landscape surrounding the airport is the reason I prefer the original images.

Ken.
 
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https://www.fsdeveloper.com/forum/t...tion-of-a-photo-real-image.441699/post-826338

Hi Gary,

I assume I did this correctly and here are my results of the ArcGIS image bgl in FSX:

(Image not included in quote)

The runways and the taxiways all line up perfectly. But noticed the runways are shorter than what's shown in the image. That's how long they were back in the 1970s and 1980s. The National Guard on the north side is totally different than what it was in 1970. It was a housing project then, but the airport bought out the property.

Ken.

Hi Ken:

Looks like you're off to a good start ! :)

More info to come soon... ;-)

GaryGB
 
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Hi Ken:

After further analysis, I have determined that the KBHM 1970 imagery BGL I linked you to via PM, is not yet fully rectified into alignment with the ESRI ArcGIS World Imagery over its 'total' extent of coverage, and it should not be regarded as accurate for use with ADE and SBuilderX to make scenery. :redflag:

That imagery is in precise alignment with ESRI ArcGIS World Imagery ONLY where the KBHM (2) main RWYs intersect.

However, as sometimes occurs with re-projection of imagery from Orthographic to Mercator cartographic format, linear measurements can lose accuracy at radial distances beyond 1 Kilometer from a central reference point.


Thus, I do NOT recommend you use that KBHM 1970 imagery BGL with ADE and SBuilderX to make scenery. :alert:


FYI: I am testing a data source from 1970 and 1978 for those tasks which may either initially substitute for- or entirely replace- the 1970 B+W imagery BGL ...that I may soon be able to provide to you by a download link sent via a PM. ;)


GaryGB
 
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Hi Ken:

I sent you a new PM with a link to download the alternate data source cited immediately above ...for testing purposes. ;)

GaryGB
 
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845
Hi Gary,

I think I'm in the right thread that I've posted about a year or 2 ago. I figured you would rather that I post here rather than creating a new one with the same topic. I I've posted that I wanted to take the Alabama scenery, developed by MegaSceneryEarth, locate the KBHM airport in the scenery, and shorten the runways by using Gimp. I've already created an airport file in ADE and have it installed in FSX. The airport is based on the time period between the 1970s and the 1980s. At the time, runway 5/23, the southwest/northeast runway, was 10,000 feet. Runway 36/18, which is the north/south runway was 4,856 feet. Now, both runways are longer. Runway 5/23, which is now runway 6/24, is now 12,000 feet and runway 36/18 is now 7,100 feet. I still want to use the Alabama scenery as my scenery, and this scenery is based on the year 2017, which would show the longer runways in the sim. When every I want to fly based on the time period between 1970s and 1980s, I turn off the SXAD Birmingham's Shuttlesworth airport scenery and used the KBHM 1970s that I've created. But if I turn on and load the MagaSceneryEarth Alabama scenery, the runways being longer in the Alabama scenery will extend beyond the KBHM 1970 that I have loaded, and you can see this as you're approaching the runway. The files in the MegaSceneryEarth Alabama scenery are bgl files. By the way, I did have version 2.0 of the Alabama scenery but now I have version 3.0, which represents the year of 2017. The only thing I know to do is to take a screenshot and clone out the extra runway length that needs shortened. I've done that but now I need to use SbuilderX to compile this bmp into a bgl file. But I continue to get the same message saying that nothing was selected, and I have selected it. I've also exported the image file as a tiff file and it still does the same thing. I did get a message saying that I may need to calibrate the image but trying to calibrate it only makes the image worse and is compressed or not correct. When I first load the image in SbuilderX, the image looks perfect. If I happen to need to calibrate it, there is no way to get the data I need to calibrate it, and besides, I zoom in and only select the area that needs the work. There is no data provided, unless it's inbedded in the scenery file. It seems to me that the scenery should have been created using a satellite image with the WGS84 projection that you've talked about. So, since there is no data provided, as I know of, there's no way to know what coordinates to place in the fields in SbuilderX. Am I doing something wrong?

Ken.
 
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Hi Gary,

I think I'm in the right thread that I've posted about a year or 2 ago. I figured you would rather that I post here rather than creating a new one with the same topic.

I've posted that I wanted to take the Alabama scenery, developed by MegaSceneryEarth, locate the KBHM airport in the scenery, and shorten the runways by using Gimp.

I've already created an airport file in ADE and have it installed in FSX. The airport is based on the time period between the 1970s and the 1980s. At the time, runway 5/23, the southwest/northeast runway, was 10,000 feet. Runway 36/18, which is the north/south runway was 4,856 feet. Now, both runways are longer. Runway 5/23, which is now runway 6/24, is now 12,000 feet and runway 36/18 is now 7,100 feet.

I still want to use the Alabama scenery as my scenery, and this scenery is based on the year 2017, which would show the longer runways in the sim. When ever I want to fly based on the time period between 1970s and 1980s, I turn off the SXAD Birmingham's Shuttlesworth airport scenery and used the KBHM 1970s that I've created. But if I turn on and load the MagaSceneryEarth Alabama scenery, the runways being longer in the Alabama scenery will extend beyond the KBHM 1970 that I have loaded, and you can see this as you're approaching the runway.

The files in the MegaSceneryEarth Alabama scenery are bgl files. By the way, I did have version 2.0 of the Alabama scenery but now I have version 3.0, which represents the year of 2017.

The only thing I know to do is to take a screenshot and clone out the extra runway length that needs shortened. I've done that, but now I need to use SBuilderX to compile this BMP into a BGL file. But I continue to get the same message saying that nothing was selected, and I have selected it.

I've also exported the image file as a tiff file and it still does the same thing. I did get a message saying that I may need to calibrate the image, but trying to calibrate it only makes the image worse and is compressed or not correct.

When I first load the image in SBuilderX, the image looks perfect. If I happen to need to calibrate it, there is no way to get the data I need to calibrate it, and besides, I zoom in and only select the area that needs the work. There is no data provided, unless it's embedded in the scenery file.

It seems to me that the scenery should have been created using a satellite image with the WGS84 projection that you've talked about. So, since there is no data provided, as I know of, there's no way to know what coordinates to place in the fields in SBuilderX. Am I doing something wrong?

Ken.

Hi Ken:

[EDITED]

Either here in this thread, or via PM, please state where you got the image you edited in GIMP that you wish to calibrate and display in SBuilderX via Add Map > From Disk.

Additionally, please state whether you changed the original size of that imagery file by altering its total Rows / Columns of pixels in GIMP while editing and/or saving.


Please provide a link to download from a online download web site such as DropBox, MediaFire, MS-OneDrive, Google etc., the edited file you refer to.


BTW: Be aware that I have located and downloaded (4) 1-Meter / pixel resolution 2017 NAIP imagery tiles for KBHM; those files are in NAD83 / UTM Zone 16N GIS projection, which must be re-projected in order to be displayed in SBuilderX via Add Map > From Disk.

I anticipate that imagery 'may' be the same source utilized for the Megascenery 2017 Alabama v3 scenery.


You may recall I had previously explained that imagery tiles displayed in SBuilderX' work-space via the built-in tile downloader will have a non-warped GIS file format, and will be automatically converted by SBuilderX into EPSG:4326 (Geographic projection / WGS84 datum ...which is graphically "warped"), when selected via Add Map > From Background for compilation into a BGL.

Imagery downloaded from ex: USGS web portals and added to SBuilderX work-space via Add Map > From Disk must already be in a non-warped GIS file format.

Depending on what GIS file format that latter type of imagery was downloaded in, it 'may' require re-projection via a GIS application before it can even be added to SBuilderX from disk ...as we discussed previously.

Pending your reply to my request above, I may have more questions that need to be answered about this project later on when I get some free time available, before I reply to your issue with how best to project and calibrate imagery downloaded from ex: USGS web portals, and which has been edited for private personal use after being derived from data in the public domain.

[END_EDIT]

GaryGB
 
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Hi Gary,

On January 3rd, 1918, you posted that you were looking into manual Geo-rectification of aerial imagery that I think you found for the KBHM 1975. I was wondering if you had the chance to GEO-rectify that KBHM 1975 image. I can't remember if you've posted or sent me that file by PM. I thought I had that image but I can't find it anywhere. I was supposed to have backed up everything from my old Windows 7 operating system but can't find it. I'm not sure where you found that KBHM 1975 image but I can't find it. I've went to Earth Explorer but I didn't see it there. You may have sent it to me by PM, but just don't remember. I do see the ones you've posted but I don't think they're GEO-rectified. It was the one from 1975. The post is on the 1st page of this thread and just scroll down to the one posted on January 3, 2018. Rather it's GEO-rectified or not, send me that file, or the link, if you can.

Ken.
 
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Hi Ken:

I will be traveling until early next week, and shall need to reply later upon my return, and after refreshing my memory on the imagery in question.

Have a good holiday. :cool:

GaryGB
 
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Hi Ken:

IIRC, you did not immediately complete a required registration for USGS access to JPL's EarthExplorer web portal, and it was not until June 19 of 2019 when I sent you a PM with a link to a 1970-era B+W BGL to be used as a large KBHM area background in a FS session linked to ADE by FSUIPC.

If you check your PM's (Private Messages aka 'Conversations') here at FSDeveloper, you should still be able to download that ZIP file from MedaFire.

The PM also contains info on the source for the imagery, and where you can directly download it from EarthExplorer.

I hope this helps you to refresh your memory on this project. :)

GaryGB
 
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Hi Ken:

IIRC, you did not immediately complete a required registration for USGS access to JPL's EarthExplorer web portal,

Hi Gary,

I probably was not registered at the time but I did registered for an account at the USGS Earth Explorer. I already have the KBHM 1970 zip file you referred to that was sent on July 19, 2019. The one I'm referring to was from 1975. But I'm not sure if you found it and sent it to me or if I found it. Here's the photo:


KBHM_1975_Aerial_Imagery_Small.jpg



This one is different from the KBHM 1970. But I'm thinking that it was you that found this file and it was a high resolution image. The one I've posted here is very bad quality when it's zoomed in. Do you remember sending me this one? I think you said that the KBHM 1970 is not the WGS84 projection. But I did use it and made a scenery from it. I don't know if it makes any difference, since it's not the WGS84 GEO-projected, but when I import it into ADE and use the coordinates that comes with it, the image is way too large and has to be rotated. Since I know the actual length of the runways, I make sure the longer S.W. N.E. runway is 10,000' and the N.S. runway is 4,856." After do that, I position the image and use the runways in ADE as a reference and adjust the image so that they both perfectly line up end to end. I also had to rotate the image so that the heading is correct. Using the ADE runways, I hope that would put me very close to the WGS84 GEO Projection.

I do have the KBHM_USGS_Topo_033086E6+7_1970+1978_Mercator_WGS84 map that you sent me, and I assume it's in the WGS84 format, and came with the text file. I've used that and I don't know if the airport is precise or not but I would guess the roads are correct, so I used that to position the roads around the airport. After placing everything, I imported, this time, an image from SbuilderX. I wanted to see how things would line up sine this map is WGS84 and the images from SbuilderX should also be WGS84 GEO projected. I deleted the map and imported the image but things still did not line up perfectly, but yet, both are WGS84 projected. So, should they have lined up at exactly same? I estimate that the runway, and even some of the roads were off by as much as 50 feet. Or is it something that I did not do correctly? I'm just courious because I always thought that any image or map that is used, or imported, that is of the WGS84 projection would line up perfectly.

Ken.

1970-era B+W BGL to be used as a large KBHM area background in a live flight session linked to ADE.
 
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Hi Ken:

Use a warped "Geographic" Lat-Lon projection / WGS84 datum (aka "EPSG:4326") GIS format if submitting data to FS2Kx SDK 'terrain' compilers.

NOTE: After source data submitted to FS2Kx SDK terrain compilers is compiled to BGL, FS' run time rendering engine "un-warps" that data and maps it onto terrain grid vertices of local 3D world ground tiles according to where those tiles are positioned in the FS spheroid 3D world model.


If 3D modeling or designing airport facilities 2D objects by tracing background imagery, use a non-warped Pseudo-Mercator projection / WGS84 datum (aka "EPSG:3857") GIS format for that imagery, (thus also FS' 2D/3D object source code) ...if submitting data to FS2Kx SDK 'airport' / 3D compilers. :pushpin:


BTW: A GIS Coordinate Reference System (aka "CRS") which is also referred to as a Spatial Refernce Syste (aka "SRS") utilizes a 'projection', a 'datum', and may also use 1 or more additional (ex: 'vertical') datums

Note that although both of the above SDK source code formats utilize a WGS84 'datum', their cartographic GIS 'projection' formats are different.


Please do NOT attempt to manually 'warp' imagery to fit by "rubber-sheeting" methods in a graphics application or via imagery calibration 'tricks'. :banghead:


Re-project imagery used to create terrain from warped EPSG:4326 to non-warped EPSG:3857 for use as imagery to create 2D / 3D airport objects.

That cartographic "re-projection" process normally requires sophisticated spherical geometry functions to be performed by a GIS application.


FYI: A 'under-documented' SBuilderX option can output a Geo-referenced non-warped 1-piece *.BMP for a background in a 3D modeling or airport design application, because it accesses / downloads original non-warped imagery tiles intact with precise GIS data from online tileservers. ;)

https://www.fsdeveloper.com/forum/threads/sbuilderx-and-blender-2-79.449019/post-855355


I have previously tested / verified this easy work-flow to do that using downloaded imagery tiles in SBuilderX. :idea:

To output a 1-piece *.BMP of selected tiles from the SBuilderX work-space in a non-warped format for use in ADE or a 3D modeling application:

1.) SBuilderX Menu > Edit > Edit INI file... (SBuilderX.INI opens in NotePad)

a.) In NotePad > SBuilderX.INI > under [Tiles] section, Edit:

ReprojectMercatorTiles=True

...and change it to read:

ReprojectMercatorTiles=False

b.) NotePad Menu > File > Save

c.) NotePad Menu > File > Exit

2
.) SBuilderX Menu > File > Add Map > From Background

a.) Follow usual procedures to download / select tiles (do not compile to BGL)

3.) SBuilderX outputs non-warped format 1-piece *.BMP / *.TXT into:

[SBuilderX install path]\Tools\Work sub-folder



NOTE: For use in ex: ADE, that 1-piece *.BMP must first be processed in ex: GIMP to make either numerous smaller tile segments, or very low resolution 24-Bit JPGs, so they can be "Added" as "Images" in ADE (using the 'pseudo-Mercator' metadata in the matching *.TXT Geo-referencing 'world' file also output by SBuilderX) ...for use as background imagery 'tiles' loaded 1-at-a-time while working on the corresponding local area of an airport in ADE.


CAVEAT: Restore normal SDK Resample compatible output of a 1-piece *.BMP of selected tiles from the SBuilderX work-space in a warped format for use in making ex: custom photo-real imagery land class terrain textures:

1.) SBuilderX Menu > Edit > Edit INI file... (SBuilderX.INI opens in NotePad)

a.) In NotePad > SBuilderX.INI > Under [Tiles] section, Edit:

ReprojectMercatorTiles=False

...and change it to read:

ReprojectMercatorTiles=True

b.) NotePad Menu > File > Save

c.) NotePad Menu > File > Exit



AFAIK, alternatively, one may use SAS Planet which also has GIS projection options for output of 'stitched' tiles to make a 1-piece satellite image from downloaded tiles:

https://www.fsdeveloper.com/forum/t...nates-in-msfs2020-from-fsx.448906/post-854869


I hope this info helps with these types of FS development tasks. :)

GaryGB
 
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Hi Gary,

I still do not understand most of what you're saying here. And I have absolutely no idea which or what images are warped and non-warped. I've googled these terms and the average layman would not be able to understand the logic behind all of this, and wikipedia is no better at explaining these things in layman's terms. These are terms that only people that have knowledge in this area would understand. These are not terms that the layman would understand, terms like, EPSG:4326, EPSG:3857, as well as WGS84. I hear and read about this stuff but have absolutely no understanding of what they are, how they differ, what they mean, and how they affect their alignment and position. I've even typed in things in browser search boxes and they would not turn up anything and go around my direct questions. And what is FS2Kx? I know you probably don't have the time to explain all of this but as long as I don't fully understand these things and be explained in layman's terms, I will never comprehend all this stuff.

Ken.
 
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Hi Ken:

FS2Kx = FS 2000 product series aka FS-2000 through FSX (including P3D version 1.4x)

GIS = Geographic Information System

EPSG = European Petroleum Survey Group (publishes a GIS projection guide citing both projection and datum referenced by single 'numbers')

http://wiki.gis.com/wiki/index.php/European_Petroleum_Survey_Group

https://en.wikipedia.org/wiki/EPSG_Geodetic_Parameter_Dataset


In the Northern Hemisphere:

"Warped" EPSG:4326 imagery appears rotated counter clockwise by 1 to 3 degrees, and vertically compressed.

"Non-warped" EPSG:3857 appears non-distorted, and is aligned properly on Earth's N-S, E-W axes without visible rotation or vertical compression.


Visual appearance of imagery may be warped or non-warped relative to how it appears IRL (aka "In Real Life") based on its GIS projection format.

Imagery may be in a number of GIS projection formats when downloaded, and must be formatted as either warped / non-warped for FS SDK work.


I believe that by now you know I would normally be much more detailed, but I do not have time to explain all the GIS info these tasks require. ;)


The understanding of GIS concepts I alluded to above is only very basic for this project; just toggle "ReprojectMercatorTiles" between True / False in SBuilderX.ini as needed for: :pushpin:

* downloaded tiles being Added from Background to SBuilderX

...versus:

* downloaded files being Added from Disk to SBuilderX


...depending on whether you require:

* "warped" EPSG:4326 for terrain elevation mesh / draped satellite ground textures / CVX land class vector objects

...or:

* "non-warped" EPSG:3857 imagery for 2D / 3D airport scenery object creation


PS: If downloaded files being Added from Disk to SBuilderX are not in EPSG:3857, they must be re-projected in a GIS application (another learning curve).


The GIS application must be able to also output Geo-Referencing Metadata in Geographic (Lat-Lon) coordinates so that EPSG:3857 imagery can be 'calibrated' by SBuilderX.

Whereas Mercator-type EPSG:3857 format imagery data would normally be in a GIS cartographic projection which is referenced / reported in Cartesian decimal coordinates, 'some' GIS applications are able to also output Metadata with Geo-Referencing Metadata in Geographic (Lat-Lon) coordinates for N-S-E-W, and/or NW, NE, SE, SW corner pixel locations; AFAIK, Global Mapper (payware) and QGIS (freeware) ...can both do this.


Note as well, that downloaded files being Added to SBuilderX from Disk and calibrated, must be in a standard 24-Bit Windows *.BMP graphic file format as discussed here:

https://www.fsdeveloper.com/forum/threads/resample-tool-not-working.448011/post-847770


GaryGB
 
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In the Northern Hemisphere:

"Warped" EPSG:4326 imagery appears rotated counter clockwise by 1 to 3 degrees, and vertically compressed.

"Non-warped" EPSG:3857 appears non-distorted, and is aligned properly on Earth's N-S, E-W axes without visible rotation or vertical compression.

Hi Gary,

Sorry it took me a few days to get back to you, and thanks for explaining these things. So, since the EPSG:3857 is non-distorted and is aligned on the earth's N, S, E, and W, this one is the WGS84 projection and is the one to choose. Am I correct? If so, how do I know if the image I'm trying to download is the EPSG:3857, or if it's the WGS84 when I go to download images? I never see that specified anywhere and maybe I'm overlooking it.


...depending on whether you require:

* "warped" EPSG:4326 for terrain elevation mesh / draped satellite ground textures / CVX land class vector objects

...or:

* "non-warped" EPSG:3857 imagery for 2D / 3D airport scenery object creation

I didn't realize this but let me make sure I understand correctly. Are you saying that if I'm working with terrain vectors or land class vector objects that I should use the warped EPSG:4386?

And if I'm working with airport scenty objects I should use the non-warped ESGP:3857?


Also, when I toggle the Reproject Mercator Tiles in SbuilderX, what exactly does that do?


Ken.
 
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So, since the EPSG:3857 is non-distorted and is aligned on the earth's N, S, E, and W, this one is the WGS84 projection and is the one to choose. Am I correct?

Yes.

But remember that both EPSG3857 and EPSG:4326 are by their very nature, already in a WGS84 datum.

It is the GIS "projection" that determines whether the imagery appears warped (Geographic aka Lat-Lon), or non-warped (Pseudo-Mercator) ...when viewed in a GIS application or other FS utility.

Imagery always has at least, both a projection and a datum; and sometimes it also has at least (1) additional 'vertical' datum.


EPSG uses a convenient abbreviated reference as a single 'number' to represent the projection and 1 or more applicable datums. :pushpin:

If so, how do I know if the image I'm trying to download is the EPSG:3857, or if it's the WGS84 when I go to download images? I never see that specified anywhere and maybe I'm overlooking it.

That would need to be specified on the web portal from which the imagery is being downloaded.

If it is not specified anywhere on the web portal (ex: due to its age and/or being old KBHM US aerial reconnaissance training "practice" photos etc.), one must analyze the imagery to see if it is visibly non-distorted; if so, it is probably already EPSG:3857 with commensurate Geo-referencing coordinates.


I didn't realize this but let me make sure I understand correctly. Are you saying that if I'm working with terrain vectors or land class vector objects that I should use the warped EPSG:4386 ?

While drawing / designing one uses non-warped EPSG:3857 imagery as a background to trace over / align to.

SBuilderX will internally re-project the resulting CVX vector source data into "warped" EPSG:4326 for the SDK compiler.


And if I'm working with airport scenery objects I should use the non-warped ESGP:3857?

Yes, regardless of whether one makes 3D models or flat / sloped GPs, and/or 2D CVX vectors for airport ground markings.


Also, when I toggle the Re-project Mercator Tiles in SBuilderX, what exactly does that do?

If SBuilderX.ini parameter value ReprojectMercatorTiles=False, satellite tiles output as a non-warped EPSG:3857 image.

If SBuilderX.ini parameter value ReprojectMercatorTiles=True, satellite tiles output as a warped EPSG:4326 image

...when one performs:

SBuilderX Menu > File > Add Map > From Background.


GaryGB
 
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845
Yes.

But remember that both EPSG3857 and EPSG:4326 are by their very nature, already in a WGS84 datum.

It is the GIS "projection" that determines whether the imagery appears warped (Geographic aka Lat-Lon), or non-warped (Pseudo-Mercator) ...when viewed in a GIS application or other FS utility.

Imagery always has at least, both a projection and a datum; and sometimes it also has at least (1) additional 'vertical' datum.

Thanks Gary for explaining. I Think I better understand things now than what I did. So, WGS84 is a datum and it's different from projection, and it's the projection that determines rather the image is warped or non-warped.

If SBuilderX.ini parameter value ReprojectMercatorTiles=False, satellite tiles output as a non-warped EPSG:3857 image.

If SBuilderX.ini parameter value ReprojectMercatorTiles=True, satellite tiles output as a warped EPSG:4326 image

I'm so glad that you brought this to my attention, and I never knew anything about this. But all this time when working with ADE and 3D modeling, I guess I may have been using the wrong parameter value. So, let me be sure I understand. When working with ADE or 3D modeling, such as in Sketchup, ReprojectMercatorTiles should be set to False. When I checked my INF.CFG, ReprojectMercatorTiles was set to True. So, I assume I've been using the wrong one all this time.

I've noticed you said when "one performs: SbuilderX Menu> Add Map> From Background." Does that mean that this toggling of the ReprojectMercatorTiles is only correct for those tiles that's built in SbuilderX, and those images downloaded from websites. like Earth Explorer, would not be correct?

Ken.
 
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I've noticed you said when "one performs: SbuilderX Menu > Add Map> From Background."

Does that mean that this toggling of the ReprojectMercatorTiles is only correct for those tiles that's built in SbuilderX, and those images downloaded from websites, like Earth Explorer, would not be correct?

Ken.

No, it means toggling of the ReprojectMercatorTiles parameter value in SBuilderX.ini is only correct for those tiles that are downloaded and assembled into a 1-piece image via SBuilderX ...when you require such an image to be output in either EPSG:4326 or EPSG:3857 GIS format.

Imagery downloaded from other websites. like Earth Explorer, may- or may not- be in the correct GIS projection and/or datum for FS tasks.

If EarthExplorer imagery you select is not already in a GIS format required for FS task(s), it will need to be "re-formatted" in a GIS application.

After you identify imagery (from among the many tiles available via the EarthExplorer web portal) that you wish to utilize for your KBHM historical scenery reconstruction project, send me a PM with details as to individual file names with specific URLs for each tile that makes up the image coverage extent you intend to utilize, and I may be able to advise you further. ;)

GaryGB
 
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