What is the best way to generate a great Sat Image?

[blackthorne556 10]

A little context - I am starting a new 40x40 terrain. I'm using a height map of 4096x4096, with a cell size of 10. For the satellite image I intend to use 4 panels of 20580x20580 for a total image size of 40960x40960 with a 1m/pixel resolution.

 

My question is this: What is the best way to generate a decent looking satellite image?

 

Here is what I have tried so far:

 

Google Maps Downloader - This has the option to input my lat/long coordinates, fetch frames at a given zoom level and piece them together. The problem I encountered was that the final product was either horrible resolution, or was missing pieces that Google did not have at closer zoom levels. I also had the problem that at large zoom levels, Google Maps would ban my IP for too many requests per 24 hour period.

 

Universal Maps Downloader - This program does the same as above, but I attempted with Bing to see if I could get better results. Not the case.

 

Global Mapper - Using the 2 week trial, I attempted to wrap my head around this program, but did not have enough money to justify the Digital Globe account to use the high-res images. To be fair, I didn't explore this option very thoroughly. I found the UI to be fairly intimidating for a new user. After pulling up the world from a free database, I was at a loss as to how to gather and save the data.

 

Screenshots - Using Google Earth Pro, I cordoned off the piece of the world I'm working with, then bisected it into my 4 panels. I then created a 20580x20580 canvas in Gimp. I did some maths, and adjusted my zoom levels in GE, went to the SW corner of my cordoned location and encountered a critical error in my thinking. The world, as Columbus had predicted, was round. It does not cut into perfectly square shapes. Now, with a little effort, I could grab more than I needed and trim the edges. Ok, but even if I ignored this problem, with a map the size I am working with, the manpower intensity is a little insane. We're talking tens of thousands of images. Not only to move around and collect, but then to stitch together. Never mind the fact that as I move west to east, the image doesn't simply pan, but the world rotates, witch relates to the first problem of grabbing square data from a spherical source.

 

What am I missing here? What is the best method to go with? I feel like I'm going to have to make a compromise, but I need direction as to HOW to make that compromise. Is there a program that should be preferred over the above listed? Was I on the right track with GM? If so, what is the preferred database to use?

 

Thanks for taking the time to read through all of that if you're still with me. I'd be grateful for any assistance.

 

- Blackthorne

 

 

[wantafanta 13]

terraincognita is a good free program id check out... also global mapper aint that hard to use... i forget who but someone made a great arma 2 map making tutorial for it.. id look it up cause its still a great resource for arma 3 map making

[RoF 241]

I built mine using terraincognita and global mapper, GM was also used to import 99% of the roads. Using them 2 programs you can have a basic terrain up and running in a couple of hours (minus download time for the sat map). Some people use QGIS, but I couldnt work out how to do anything in that lol

[blackthorne556 10]

Ok, so I've got TerraIncognita up and running. I've made my selection using my coordinates. A bit of searching tells me that to get 1m/pixel resolution I want to set zoom at 100meters. The small guide I'm reading from also mentions Global Mapper, and says that he is saving in ArkView format for compatibility.

 

So, before I launch such a large download, let me run some numbers here.

 

I want my final map to be about 40x40Km. I've gathered my heightmap from OpenTopo, and the area I seek to emulate is 90x90, so it will be slightly downscaled. So I take my slice of the world, and I scale it to 4096x4096, and would put that into TB at cell size 10. Compatibility pending, I may recapture the data in GM, but we'll see.

 

So if I gather the sat images from Terra, then import that to GM, cutting it into 4 panels, can I then scale those to 20580x20580. If so, when I set that to 1m/pixel, everything should in theory match up at the desired size, Correct?

 

Or am I missing something that will screw me in the end?

[RoF 241]

In TerraIncognita your have to save as oziexplorer map, then import the *.map files into GM. Sounds like you doing a huge image. I find it best to import five .map files at a time into GM, otherwise it tends to crash, it will also most like say not responding, but just wait it out.

 

I'm also not sure how you would down scale a terrain in GM, I'm guessing your have to change the settings when you export it. I just use 1:1 for ease of use. Also you want to split it to 20480x20480 not 20580x20580

[blackthorne556 10]

Derp. Yes. 20480.

 

I do currently have a heightmap generated from OpenTopo. It's at 4096x4096 already. I'm thinking that I might just use GM to create the sat a map from the pieces I collect from Terra, and tile it into 4 panels of 20480x20480.

 

Unless I'm mistaken, I could then copy those, and make a downscaled image from them and line them up with my height map to confirm a good match.

 

Once that is done I can move on to my mask. Can I assume that TB will read 4 mask images just like I'm doing for my sat image, and do that in 4 panels of 20480x20480 as well?

[RoF 241]

Yeah TB will do that fine, My heightmap is 4096 with both the sat and surface split into 4 parts each.

 

Did you make you height map using GM? As when you open the sat images in GM, it will put them right over you heightmap, then you just export it as a raster (use .bmp for speed)

[blackthorne556 10]

No, I gathered my heightmap from http://www.opentopography.org/

I am using the coordinate input for both, so I would hope that (once scaled appropriately) they would line up.

 

Also in reference to your earlier comment, I had considered using a 1:1 format, but the piece of the world I am trying to work with has so many interesting features, but I needed about 90x90km to take advantage of them. Hopefully this all works out, or after shaking off the disappointment I may be forced into a 1:1

[RoF 241]

That heightmap you can open in global mapper, as your want to set the projection to UTM, otherwise I think your sat image might be slightly skewed and wont line up... maybe.

 

tbh 1:1 is very easy if your just starting out. Also 40km is huge to work on, I often regret making such a huge map lol

[blackthorne556 10]

Yeah, I know I bit off a pretty big bite to chew on. The upside is that we have a resident Xcam expert in the unit to teach me how to populate it and provide assistance. I just have to figure out the base layers. Once I get heightmap, satellite overlay, mask, textures, and clutter all hammered out, we can get to fun stuff.

 

According to my Xcam guru, there are ways to get large areas done with randomization algorithms. That will do for "painting" large portions of the map, and we can go on to fine tuning from there. I keep getting disappointed by maps that are either really nice but too small, or big enough but ugly. That's not to say that there aren't some out there, but there are a lot more maps than there are good maps.  :lol:

 

Some of my unit have worried about performance, but with the DX12 compatibility on the horizon, hopefully those of us who have invested in decent hardware will be alright. Those who have not really shouldn't get to set the standard :P

 

So I've got Terra downloading in oziexplorer format. It's a huge download, so hopefully it works out. Either it will work - whether with some stretching/scaling or not - or it wont and I'll just have to bite the bullet and change some sizes and rethink which parts of my slice of the world are most important to me for inclusion.

 

Thanks for the help so far. I'll report back on how it goes.

[RoF 241]

I wouldn't really worry about performance, I've got 2m objects on my map and get a steady 30 fps and I'm on an old pc. Also with TerraIncognita I find bing has better sat images than google, theirs tend to look like a patchwork sometimes lol

[blackthorne556 10]

Well, I ran it with google maps. It didn't stop part way through like some of my projects. Unfortunately, there are many pieces missing. I'm assuming it leaves blank any places that don't have a file associated with the zoom level... Any thoughts?

[RoF 241]

Try setting it to use Bing aerial. Also it wont download any ocean, so them bits will be missing.

[blackthorne556 10]

Yeah, the ocean is fine. It's the deep jungle that I wish it would grab. I'm going to try grabbing the same zoom of the area with Bing. If that doesn't work I might try zooming out a bit and super imposing the best image on top of a stretched version of that. Hopefully that doesn't look TOO ugly.

[RoF 241]

If it's just jungle, couldn't you maybe clone a bit from somewhere else in Photoshop and blend it in

[blackthorne556 10]

Yeah, I hadn't thought about that. The distance at which the sat image renders, I'm sure I could get creative enough to blend it in. I had hoped to avoid employing my extremely limited photo editing abilities, but if Bing lets me down, I think that may be the answer.

 

Still waiting on the Bing Download... 90km x 90km at 100 m (well, 150 yard for Bing) is a great many panels.

 

You were right about the Google results coming back patchy. Hopefully Bing's look better across the board and I can JUST use that, if not it will be a case of superimposing them and cutting out the one that looks worse. I suppose I could select the areas and adjust with color controls as well. Hopefully, between the 2, I can get all the non cloneable parts to show up without these damned clouds...

[wantafanta 13]

In TerraIncognita your have to save as oziexplorer map, then import the *.map files into GM. Sounds like you doing a huge image. I find it best to import five .map files at a time into GM, otherwise it tends to crash, it will also most like say not responding, but just wait it out.

 

I'm also not sure how you would down scale a terrain in GM, I'm guessing your have to change the settings when you export it. I just use 1:1 for ease of use. Also you want to split it to 20480x20480 not 20580x20580

 

well, depends on if you have enough space on your main HDD for Global mapper to cache all the data to... i think you can change the default location of the cache though.

[blackthorne556 10]

So, a little update - http://imgur.com/a/v2qVC

 

That's the top left panel of 4. Before and after editing. I think I did pretty god for my first go at GIMP. Thanks for the tip about the clone tool. Infinitely useful. So far I've used it in creation of the shoreline, adding trees to the low res sections that I cut from further zooms and stretched, and for "erasing" the clouds.

 

Thanks for all the help. I'm sure I'll be back with another hangup sooner or later!

[RoF 241]

You might want to change the sea color, otherwise bits of your beaches will look dark blue. On Altis they seem to have used a gradient, I've been changing mine in last couple of days, I took a colour of a beach as the forground colour then darken it, to have a light to dark gradient. Have a look at "P:\a3\map_altis\data\layers\01_01" all the S_xx paa** files and your see how BIS do their sea.

 

**You can use P:\TexView2\TexView.exe to open .paa files

[blackthorne556 10]

Alright. So I will have to go back and deal with the coastline after I finish the rest of my panels.

 

So in editing, obviously I had to switch to RGB format. After all my editing is done and I'm ready to import my final images, can I switch back to indexed to cut down on size? Is that possible, or advisable?