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View Full Version : HOW DO I - Convert a front facing image into a top-down image for maps?



anomiecoalition
03-03-2013, 12:44 AM
I'm not an artist or graphic designer, I just like making maps...and although there are tons of great symbols for free download on Dunjinni and other spots, I'd like to try my hand at making some myself (or converting existing front facing images into a top-down view).

Lets just say for the sake of argument that I wanted to turn this image into a top-down view...

52589

Wondering if anyone can point me in the right direction of a program or method that has a reasonable learning curve.

Mark Oliva
03-03-2013, 02:16 AM
Lets just say for the sake of argument that I wanted to turn this image into a top-down view...

Wondering if anyone can point me in the right direction of a program or method that has a reasonable learning curve.

If someone can tell you how to do that, I'll be all ears. The top down view requires graphical information that isn't included in the front view. Therefore, it's not possible in my opinion to turn this front view into an accurate top down view. On the other hand, there might be some software available that can attempt to analyze the front view and synthesize what it's top down view would be. Based upon different kinds of synthesizing software that I know, the results would not always be what one is seeking but sometimes those strange and wonderful results that only the good lord usually is credited with achieving.

waldronate
03-03-2013, 03:29 AM
To a first approximation, those horns will look pretty much the same when viewed from above (the embossed bits where the horns join are going to be different, but it should be possible to project that onto a cylinder and the view that cylinder from above; I vaguely recall that one of the Photoshop versions has a feature like that). The background plate will be pretty much just a little rectangle - think of a book viewed from the front and then from above.

Urist
03-03-2013, 11:47 AM
As has been said, information about the top doesn't exist so you will need to make it up.
With pen and paper, I would put the front image below where I want the top-down image, then transfer vertical edges up. Then draw horizontal lines connecting the vertical edges based on how far you think they are depth wise. Lines that you wouldn't be able to see are not drawn or drawn as dashes. Curves, of course, complicate things.
Here is a quick example I did in inkscape.
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On a computer I would likely try to convert to a line drawing, then use inkscape to save it as a .dxf, then import it into a 3d CAD program and make into a 3d model and use that model to generate a top-down image, but there is usually a little bit of a learning curve when working in 3d.

Then all that needs doing is textures.

Gamerprinter
03-03-2013, 03:00 PM
I create top down objects based on frontal view photos all the time, primarily because photos are generally not taken of top downs on given objects. Nobody but cartographers think in 'top down' terms. When I needed a top down view of skeletal dragons for a map, what did I use for reference? A side view photo of a brontosaurus skeleton. I use my imagination seeing the side view photo and think about what it might possibly look as a top down and then create. I know of no software that presents such views from a given object - it just doesn't exist.

I don't have the original photo anywhere that I can find, so here's a section of a past map with my top down dragon skeletons, so you can at least see the final result.

This is from my One Page Dungeon Contest entry from a couple years ago...

GP

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anomiecoalition
03-03-2013, 11:52 PM
Thanks for the responses everyone...all in all - sounds like there would be quite the learning curve (being that I was not blessed with any talent for drawing.) Perhaps once I get a little further with my dissertation I'll have some time to try to learn one of those 3d modeling programs...or learn to draw :)

BTW - @GamerPrinter - awesome skeletons

Midgardsormr
03-05-2013, 03:11 AM
There are some software solutions that can take you part of the way, depending on the image. If you have two or more images of the object taken from different viewpoints, and you know the field of view of the camera that took them, there are some programs that can use that information to create a partial 3d representation of the object. Such programs are not cheap, though, as they're generally used to create visual effects for film. The cheapest one I am aware of (that works) is called Syntheyes. There was an open source one called Jahshaka or something like that, but it never really worked. They're also not easy to learn, or to use once you've learned them.

I have also seen some software approaches to using depth of field information (the difference between sharp and blurry parts of the image due to focus), along with perspective and contrast to extract depth information from an image. This works best for landscapes, where you get a significant amount of atmospheric perspective, strong focus cues, and easily approximated vanishing points. I have yet to see such a program do anything close to automatically, though. This kind of software is used to assist in converting 2d movies to stereo 3d. My last job involved evaluating every such program I could get my hands on, and most of them weren't worth the time I spent downloading, much less what I spent learning to use them.

In short, Urist's method is the simplest, cheapest, and fastest way, and it's the method that's been used by drafters since long before computing was a thing. Though usually it's used to go the other direction: to create elevations from a floor plan. I once read a really nice book on theatrical set design that gave some excellent examples of how to transform concept sketches to set layouts and vice versa, but I don't remember the title. If you happen to have a theater supply shop in your area, or a college with a theater department, you might thumb through their books and see if you can find something of that sort.

Korash
03-05-2013, 10:14 PM
I know you want to do this yourself, but I had a go at doing as waldronate suggested (and also my first go and VERY quickly) and I have to agree with him. see attached:
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anomiecoalition
03-16-2013, 03:14 PM
Thanks for all the advice guys (and thanks for the Horns Korash!). Hopefully we create a light challenge to make objects so I have additional incentive to try out some of these techniques.

Bogie
03-16-2013, 04:44 PM
I am constantly taking pictures of objects from a top-down perspective to make some of the objects I use. Everyone looks at me funny, including my wife.:P

Korash
03-17-2013, 08:28 PM
##############

Bogie, I started to write an inappropriate response, but thought better of it ;) All I really need to say is that your work is well worth a few "strange" looks :D

@ anomiecoalition, you are welcome, but like I said, first try and quick, but it does prove the point that sometimes just thinking bout the object in a different light is all you need. I just removed the plates and added two blocks with some gradient to it. Didn't touch the horns at all. Was gonna try and figure how to rotate the crest but decided not to...

Donna111
10-27-2013, 10:41 PM
HI there
I think there must be an image converting program which supports to Convert a front facing image into a top-down image for maps.You know there are all kinds of image converting tool (http://www.rasteredge.com/how-to/csharp-imaging/image-converting/).
You can just choose the most suitable one for you .It would be more convinient.Best wishes!