How do YOU create various resolutions of the same map?

[Jaxilon]

For example, a world map and a zoomed in regional map showing greater detail.

My first instinct is to create one huge map at the regional resolution and then just shrink down the world version. Obviously there could be some issues such as rivers no longer showing and so forth but it would ensure everything was in the exact right location. Possibly some of the features could become muddled however.

Then I thought, well, perhaps draw the original coastlines and shrink that down and then fill in all the stuff you want to show on the world map. The problem there is the challenge of placing the mountains and everything else in the exact locations as the regional maps would later show with greater detail. This seems like twice the work since you would be drawing the same area features in two different resolutions. That seems less than efficient unless you just want two entirely different looking styles in which case it's not a big deal.

I would love to hear how others have handled this.

[Redrobes]

I write an app which is specifically designed to alleviate this issue. See sig. So naturally this is the way I do it. I don't have a fixed resolution image for the map.

[guyanonymous]

I write an app which is specifically designed to alleviate this issue. See sig. So naturally this is the way I do it. I don't have a fixed resolution image for the map.

Can you export the maps you create in viewing dale at full size (e.g., massive resolutions like 30000x___) or as tiles for use in googlemaps?

[Redrobes]

Can you export the maps you create in viewing dale at full size (e.g., massive resolutions like 30000x___) or as tiles for use in googlemaps?

In the app you zoom the map so that you get on the screen what you would like to export. Then you can export the screen image as a BMP, PNG, or JPG and you can set the resolution. You can set that as either a DPI with image size in mm or inches and it will calculate the pixel size or you can set the pixel size directly. It will make the aspect ratio whatever you had the apps main map window set to.

You can easily export up to about 20,000 pixels wide but as you go higher then it will start to struggle because of the limitations of the file formats and the PC memory required to render the screen image. Generally, whatever the app, I would say that about 10,000 is the max anyone should export images at. I have various apps which start to generate rendering issues after about 14K square. Gimp and Photoshop are almost certainly able to cope tho. Remember that if a pixel is 4 bytes then 20,000 square is 4x20x20Mb or about 1.6Gb of image.

There is no option in the app to export a set of tiles which line up in a grid but there is an option to import a large image and have it break it up into tiles and import it. So it will import 20,000 pixel images into it. Using arrays of images from tile commercial sets, I have imported a 100,000 pixel square bitmap into it. Its slow of course but it will cope with it.

There is a setting where you can request the map as an image over a web page interface so that you can get a web browser to view the image with the correct URL. In the URL is the X,Y, zoom and image size. If you got a script to ask it for a set of tiles of the map and changed the X and Y values and saved out all of the images then you could get it to make lots of map tiles that way. That's not a trivial thing to do but it could be done. If your looking to serve up the map to players using a browser only then you can note that the app has a map web server built in for that purpose. But you would not be able to host that on the net as a web page hosted by some web company. Your machine running the app would be serving up the map images.

For googlemaps or some other similar map serving java I guess it comes down to the requirements of the images it needs to build up the page. A quad of 20K square images would get you a pretty deep zoom image for a google map tiling app to run with tho.

[guyanonymous]

Redrobes,

Interesting. I really should check it out someday....it's only 'being stuck in the app' that's held me back since.

If I understand right, I can zoom out to encompass the whole map, export that at 20000pixels (or so) width, and it will include details that would resolve at that 20000 pixel resolution as though I'd had a 20000x____ window open and done a screen capture? (e.g., all the detail would be there)

I've found 30000x15000 or so is the max. size that compfortably works in -most- programs I've tried. Granted, I've not printed anything out that's 100 inches/50 inches, but you never know - I want to be prepared.

Do people need to own the viewingdale software to view the maps served on the web?

Thanks!

[Redrobes]

If I understand right, I can zoom out to encompass the whole map, export that at 20000pixels (or so) width, and it will include details that would resolve at that 20000 pixel resolution as though I'd had a 20000x____ window open and done a screen capture? (e.g., all the detail would be there)

That is correct. It is NOT like a screen capture scaled up to 20,000 pixels, its, as you say, as tho you had a 20,000 pixel screen so that detail which would be at the 1 pixel res is still there in the export. I had a video showing that somewhere. If I find it ill link it.

EDIT - Here it is:
http://www.viewing.ltd.uk/Temp/CG/VD...Demo1_xvid.avi
Its a bit long. Start half way through to see it save a 12,000 pixel image with 1 pixel detail.

Do people need to own the viewingdale software to view the maps served on the web?

Theres two modes of seeing a remote viewingdale map. You can a) use the VTT aspect of it where you locally generate the transferred map on your local copy of viewingdale. In that case you can modify the map locally and everyone gets the changes sent back. Its also super fast (realtime) scroll and zoom. For the VTT mode you need a copy. Or there is b) where you can set one master copy of viewingdale to act as a web server for the currently loaded map. In which case other people can use just a web browser only to request an image of the map at a set X,Y & Zoom and image size. In this case you can look at the map at different positions and scales but you cant edit it. You cant get a grid switched on or off or do very much. You just get an image. In a similar way that say google maps sends out tiles of maps to view but not edit. Note also this mode is served from the app not a web site. With your browser you need to ask for the image at your local IP address and do all the normal port forwarding for being a web server as opposed to normally being just a web client.

Using a combination of the two you can play the game with some people using a copy editing the map and have a couple of people using a web browser and they could use browser refresh to get a new image with changes made by the DM and other VTT players but he would have to request someone to move his characters icon.

If you have a static IP address and an always on windows box server then you could make web pages with links to your viewingdale web service so that you could have a wiki or a web based map and have links to map images which might change if you edited the map with the app. I.e. it would be a dynamic up to the minute view of the map areas without any need to FTP upload new static map images to a web site.

Hope that explains it.

[guyanonymous]

Thank you for the great explanation!

[Jaxilon]

You are correct RR and I should have guessed what your answer would be . In the case I am thinking of there would only be two images of different resolutions.

I recall a challenge we did some time ago of various locations from our CWBP and at the end you used your application to overlay our regional/area maps on the world map which was very cool. It also happens to have shown the very issue I am talking about because some of the entries did not line up as well with the original world map.

I guess in the end if the resolutions between the two are large enough it doesn't make any difference but if the world map shows any sort of features then to my mind they need to match.

[Hai-Etlik]

Vector graphics, or better yet, unsymbolized vector data in a GIS.

Also, simply zooming in doesn't really work very well. A projection suitable for a world map, isn't generally a good projection for a continent, and a projection that works well for a continent, isn't necessarily a good match for a single city.

[Mark Oliva]

We use only raster graphics, no vector graphics. Nonetheless, or main mapping program, Fractal Mapper (TM) 8, has multi-zoom functionality that makes such operations very easy. It's described in our free 220-page PDF tutorial, You can get it at:

http://www.vintyri.org/vintyri/tu1.htm