geophil wrote:
But why are you merging in MicroDEM and not in TransDEM directly?
I don't want to use transdem to do the DEM merging because trying to merge 100+ dem files one at a time using your software is painfully painful.
First I am required to let transdem convert the dem to .dem format. and then save into that format.
1.Open dem, let load, save dem as microdem format.
Repeat 100 times.
2.THEN I must also open the first dem, and ADD DEM 100+ MORE TIMES. Each time i must let the dem load and repaint, by the 100th dem, transdem is slow and too painful to keep using it to merge dems.
Your software won't allow multi-selection dem adding, which forces one to move to other programs to do mass dem merging.
SIMPLY PUT, MICRODEM allows one to choose ALL THE DEMS THEY WANT TO MERGE in a single operation.
geophil wrote:
One of the objectives of TransDEM was to avoid other 3rd party software as much as possible. Instead raster and vector map sources should be processed directly.
The current transdem orthographic map server resources, suck.
Also the transdem interface for downloading map files displays each file and loads them all into ram WHEN DOWNLOADING, if you download 1,000+ tiles, transdem becomes unusable (slow) for the download part.
IT can USE that many tiles, but when it DOWNLOADS them, its programming slows to a crawl due to all the maps being loaded into ram.
Other programs that cache map tiles do NOT keep them in RAM, ONLY WHILE downloading so the download remains constant and speedy.
Im not complainin, the program is cheap in cost, fine, but it is what it is.
Its, limited, and I am trying to work around those limits.
--->Many of the map tile and wms services no longer work properly, someone needs to go thru them and update them and add more, since many were retired for newer better ones that transdem dosen't have listed.
For instance, none of this ortho imagery is accessable in transdem, the server isn't listed, even tho its available and free, and not restricted by GOOGLE.
https://basemap.nationalmap.gov/arcgis/ ... /MapServerI am not smart enough to figure out how these services work to add them to your program, but I am smart enough to find the servers and see that they exist.
I could post them here and ask you how to add them...
Google has some nice orthographic, but they HIGHLY restrict its use, and even restrict the amount of tiles you can download to a very very restricted level if you want ANY KIND OF ZOOM CLARITY AT ALL.
The google service is painstakingly slow also. And EVEN if you pay them for it, it won't work because it requires their signature, which you don't support, and they still restrict the bandwidth and total number of tiles.
So I found a ortho resource that allows high speed and high volume x20 images
I would like to add this tile map server to TransDEM, but I can't figure out how.
http://server.arcgisonline.com/ArcGIS/r ... rver/tile/Which has a 20 zoom level available.
The url is structured like this:
Base:
http://server.arcgisonline.com/ArcGIS/r ... rver/tile/Code:
GetUrlScript
begin
ResultURL:=GetURLBase+inttostr(GetZ-1)+'/'+inttostr(GetY)+'/'+inttostr(GetX);
end.
Code:
[PARAMS]
pnum=
GUID={7B743985-BC5F-4AB6-8915-AC5DBBB8F552}
name=ArcGIS.Imagery
NameInCache=ArcGIS.Imagery
ParentSubMenu=ESRI
DefURLBase=http://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/
ContentType=image/jpeg;image/jpg
Ext=.jpg
projection=1
sradiusa=6378137
sradiusb=6356752
Code:
Info
ESRI<br>
<a href="http://www.arcgis.com/home/webmap/viewer.html?useExisting=1">www.arcgis.com</a>
I see there are tons, ESRI servers would be good ones to add... but i don't know HOW.
You can download these two files that contain all the different urls and how they are formatted.
https://bitbucket.org/sas_team/sas.plus.maps/downloads/https://bitbucket.org/sas_team/sas.maps/downloads/Inside the files you will find tons of different map resources.
I would add them to transdem and share the export file here, BUT i don't know how the map servers work at all.
You show one of them, The usa Topo Raster 1:24k Raster tile service uses the arcgisonline.com sites, but DOSENT WORK.
Of that huge list from the sas zip file downloads, i got ONE to work.
And it only works to 16x, making it not that useful for placing trainz objects.
So clearly all these companies that got all their data from satellites paid for by the us citizens now are somehow blowing thru all the rights we have to the data, and are now charging an arm and a leg for it all, or requiring users to "sign up" and get the data thru their proprietary software?
Is this where its all going now?
Its about time the data, is revoked, by the American people, that should stir up some attention and get it all back to where it should be, free.
So ones only option is to do what im doing, try to download the data while YOU STILL CAN.
Using programs like SAS.Planet. and TILE MAP SERVERS that you run yourself.
Thats where I am now, trying to get the data i acquired with sas.planet into transdem.
So far, i can only figure out
that I must manually georeference each raster i create from sas.planet into transdem using geo points and the like..I was just trying to make that more accurate by not doing it manually with the human error involved.
So a few reasons im not using trans dem to merge dems and to download the tiles, is:
1. Transdem cannot merge multiple dems at once.
2. Tansdem cannot do multithreaded tile downloading, and must keep all tiles in RAM while downloading, slowing the download logic, each url request slows down incrementally based on the amount of tiles currently loaded. So each tile loaded will slow down the rest of the tiles downloading, after 300 tiles, transdem's 300th tile request rate is measurably slower than the first requested tile. Other map tile downloaders, downloads 63 threads at 50Mbps... On the same pc/internet.
3. It also will not reuse already downloaded tiles for the same zoom and area, other programs DO, like sas.planet.
Wasting so much data that googles or other map services become prohibitively expensive. When your tile map pathway has gaps, and many of them you must re do the path and re-download.
Do that 3 times, and you have exhausted your quota, because transdem will download tiles for the exact same identical area, again. But just rename the file, and keep both.
Even if you "fill in the gaps" you now have much more downloaded overlaps, causing much more hd use and ram use, and pc slow down.
U can't win without
GRID BASED map caching. checksum the tile, grid the checksums, checksum the grid of check sums, and you quickly scan. scan the checksum grid for missing... download only missing, have option to download only if different.