plugin for DEM manipulation

[doonee]

hi all..

does anyone know, by any chance, if there is a PS or PSP etc plugin
out there, designed to faciliate the manipulation of greyscale digital
elevation models ?

the followng link may be known to many, but it nicely illustrates the concept
of DEM manipulation, so im adding it ....

http://www.shadedrelief.com/dem/dem.html

regards
d.

[Racc Iria]

I'm not quite sure what you're asking. I read through the information at the link you provided. It's my understanding that the DEM image being edited in Photoshop would just use the standard tools available and that the image would just be a standard 2D flat view from directly overhead.

Special software or a 3D modeling application using a displacement map is needed to translate the lightness values into 3D "terrain."

Can you edit a such an image in Photoshop? Yes, I've done it (although a long time ago). Is there a way in Photoshop to view it in 3D while you paint on the 2D image... none that I know of.

However, what I've done in the past is have the image applied as a displacement map on a higly subdivided plane in a 3D application. While that application is open, launch Photoshop and load that same DEM image. Paint the changes, then switch to the 3D app and update the displacement map. Go back to Photoshop make more changes, switch back and update the image, etc. It's pretty quick working that way once you've got it set up.

--Racc

[Kraellin]

http://www.reliefshading.com/softwar.../CartaPGM.html

Craig

[doonee]

@racc

I read through the information at the link you provided. It's my understanding that the DEM image being edited in Photoshop would just use the standard tools available.

Yes, the people from that article appaar to be working with standart tools and suggest their use.
I just wondered whether there were, as is so often the case, any specialzed or workprocess smoothening gadgets in the form of plugins etc floating around. (There are dedicated height field editors out there as well, but i was curious of what was possible with Photoshop).

Is there a way in Photoshop to view it in 3D while you paint on the 2D image... none that I know of.

*That* would be a great idea for a plugin, but i didnt think of that when i was asking.

Paint the changes in PS, switch to the 3D app and update the displacement map. Go back to PS make more changes, switch back and update the image, etc.

Good idea!.
I will check this out.
You did that with MAX, correct ?

rgds
d

[doonee]

@craig

thanks craig !!

d

[Racc Iria]

doonee...

Yes, I was using MAX.

I remember a long time ago when I was doing this, there was a program called VistaPro which was basically a terrain, sky, and plant generator and renderer. It came with a lot of grayscale DEM images based on satellite scans of the Earth. I used some of those as a starting point, and using the dual application process I described above made the changes in Photoshop.

I do remember however that the results were a lot better when I started with one of those base images than trying to paint one from scratch.

--Racc

[doonee]

racc

VistaPro is still around, and still has a community, but it uses a sort of customized DEM, known as VistaProDEM, a simplified (?) format fancied by other apps from that time, like GenesisII.
Nowadays, I would say, Terragen or Vue5I, who both import greyscale BMPs, have become more popular.

The dual application process you describe is sounds cool, how do you get your work out of MAX tho ? (supposing you would want to get out.)

I'd like to find out how i can increase (invented) detail on my DEMs, maybe add a riverbed (like shown in the link).
Another thing id be curious about is whether i can manage to add 'fake forest bumps' to these DEMs, groups of large amounts of small semi-spheres, slightly raised above surface level, to see if i can get away with using these
as distant forests.

[Kraellin]

you know, this may sound silly, but there are game engine and game engine editors that work in 3d and can handle the import of .pcx files and others probably, that can translate the .pcx data into 3d imaging. and at least one older game engine could handle grayscale imports for terrain. also, the quake engine, which drives many of the top 3d games these days, has a free editor. i dont know if it allows for dem import or any other type, but it's worth a look.

Craig

[Racc Iria]

From doonee:
VistaPro is still around, and still has a community, but it uses a sort of customized DEM, known as VistaProDEM, a simplified (?) format fancied by other apps from that time, like GenesisII.
Nowadays, I would say, Terragen or Vue5I, who both import greyscale BMPs, have become more popular.

The version of VistaPro I had allowed you to export the proprietary DEMs as a standard grayscale image format, which you could then edit with any image editor. I never bothered to upgrade to newer versions and eventually stopped using it. No particular reason, I just let it die. I do use Terragen on occasion.

From doonee:
The dual application process you describe is sounds cool, how do you get your work out of MAX tho ? (supposing you would want to get out.)

I'm not sure what you mean here. The purpose for me was to generate terrain for use in 3DS Max. So, once I had the scene the way I wanted it, I would render the animation in whatever format I needed. For the purpose of this discussion I was just suggesting using Max to view the terrain in 3D while painting the changes in Photoshop thus allowing you to see how the changes you made to the DEM would be reflected in a three dimensional interpretation of the grayscale image.

From doonee:
I'd like to find out how i can increase (invented) detail on my DEMs, maybe add a riverbed (like shown in the link).

That's why I started with an existing image based on real world data then used the Clone/Stamp and other similar tools in Photoshop to get more realistic results.

From doonee:
Another thing id be curious about is whether i can manage to add 'fake forest bumps' to these DEMs, groups of large amounts of small semi-spheres, slightly raised above surface level, to see if i can get away with using these
as distant forests.

My guess is that this would look more like "3D Fish Scales" or "raised pockmarks" rather than a forest. If you are going to use MAX to render your scene, I would just create a real loy-poly count tree trunk with a couple of branches. Create the canopy of the tree using a deformed sphere and make the leaves with an RGB foilage map and an opacity map. Then group that together and put a bunch of 'em off in the distance. The Scatter modifier might be useful for that.

Or, if you really need a lot of them, render one of the trees as an image with alpha, and map that onto a flat plane, add a Look-At constraint that points at the camera, then make as many instances as you need of the plane and position them in the scene. Rendering will be a lot faster.

If you plan on importing your custom DEM image into something like a VistaPro or a Terragen, just let that application render any trees, or foilage, etc.

Which reminds me, you never really said what you wanted your final output to be.

--Racc

[doonee]

@craig

that don't sound silly at all ...
a heightfield is a heightfield, whether 'invented' or not.
(not too sure tho if quake has heightfield, as would flight simulator etc.)

Dayton Leveller, for example, is used for both games and 'real life' stuff.

However, I'm somewhat determined to learn how to mess with these DEMs in PS.
The thing is, and i hope that *this* doent sound silly. i cant even do the simple stuff in PS, like create an evenly shaded sphere and such (which i google for and shamefully download if i need one), hence the hope for a 2D/3D greyscale plugin. I guess just i got to work up on all this to become more competent when messing with DEMs in PS.

[doonee]

racc

The purpose for me was to generate terrain for use in 3DS Max. So, once I had the scene the way I wanted it.

oh, darn i didnt think right ....
of course youre right, no matter where one takes it,
one always has the DEM.
(got MAXed up for a sec ... ...

but, just btw, does MAX export DEM ?

My guess is that this would look more like "3D Fish Scales" or "raised pockmarks" rather than a forest.

Actually, the comment about the bumped forest was exclusively Terragen specific (without making that clear); Unless one really wants to go TerraGen and no other, there's no need to paint forests onto DEMs.
And you're right, it does look cranky, but since Terragen has no option for vegetation representation at all (sadly), one is ocasionally lead astray.
However, for Terragen, there is a small app, called Terramaker, which allows you to implement such artefacts into an existing terrain, and adjust their specific height acording to the underlying landscape.
Its ok for faking satellite footage, since one often only needs the shadows of forest blocks, and there is no poly issue at all.
As long as you dont come any closer than a mile or two to these things, they dont look too bad.
Youre right tho in pointing that it works better in faking pointed conifer than rounded broadleaf canopies.

I wish i was better in creating these structures (blocks of spheres etc.) with PS from scratch, that would improve my workflow a lot.
Im such a looser in PS.

you never really said what you wanted your final output to be.

actually, output is twofold.
For really long distance POVs, like fake satellite footage, i had considered TerraGen. (this is where the fish-scale forests come in).
For closer POVs, im planning to use VUE (where the work consists rather in producing the apropiate trees).

When having to render large amounts of trees, the way to go, lately, seems to be VUE5I, whose ecosystem technology handles poly plant models as part of the texture, and populates surfaces automatically with lo poly models ....
Im playing with it since a few weeks and as far at that particular issue goes, its quite impressive.

This particular tree-job has to do with showing precolumbian brazilian landscapes, which means *a lot* of forests ..

But my topic here is more general, it has to do with my limitations in Photoshop, really ...

[Racc Iria]

doonee...

As far as I know, MAX doesn't really use any form of DEM data at all. All it does is offset the vertexs of a mesh based on the lightness values of a grayscale image (any image really, but grayscale gives the best results). There's nothing to export since MAX is already using the grayscale visual representation of the DEM data, which must have already been created.

I suppose one could write a script that would report the offset of each vertex in the mesh, determine a lightness value at each vertex based on that offset, and render out a 2D image of those values. But that's beyond my abilities.

I haven't used VUE51, but from your description it does sound like it's the best solution for you concerning the vegetation.


Here's a quick tutorial on how to make a grayscale "sphere" in Photoshop:
1. Make a circular selection on a new layer.
2. Select the radial gradient tool.
3. With white or light gray as the foreground color, click and hold where you want the highlight then drag out past the marching ants of the circular selection. Let go of the mouse button. You should now have a basic shaded sphere.

See attached images.

[doonee]

racc

I suppose one could write a script that would report the offset of each vertex in the mesh, determine a lightness value at each vertex based on that offset, and render out a 2D image of those values. But that's beyond my abilities.

i dont blame you ,,,
i dont thinks thats necessary either, but thats where i got stuck (maxed up) for a sec with my answer...

I haven't used VUE51, but from your description it does sound like it's the best solution for you concerning the vegetation.

DO check out 'silent spring' under the 'scenes' button at:
http://www.graphique3d.republika.pl/
(VUE5I ecosystem showcase)

about the greyscale spheres:
how do i control whther the shading of the sphere is centered ?
how can i tell that the shading is really sphere-like ?
see examples 2 and 3 from the left in primitives.jpg (in attachment)

as for the terragen distant fish-forests, i attached a quick (lofi) example ...


thanks for the help!
d

[Racc Iria]

doonee...

I took a look at the "Silent Springs" images. Some very nice stuff there. I bookmarked the site so I can read more about when I have more time. Thanks for the link.

To center the shading, your initial click point should be the center of the circle, then drag to the edge of the circle selection, but don't pass it, and let go. That should give you the example of the 2nd sphere from the left in your image and the 1st example on my last image.

When making the circle selection, holding the shift key will keep the selection perfectly circular, and holding the alt key at the same time will draw the circle selection from the center of where you click.

To help you determine the center of the cirlce, you can use guides. To use them, first make sure you have turned on the rulers (View>Rulers). Once they're on, make the circle selection. Then, click on the top ruler and drag down to create a guide, it will snap to the edges and center of the selection. Do the same from the left. If you can't see the guides or they aren't snapping, make sure EXTRAS is checked in the view menu, and that GUIDES is checked in the SHOW submenu. Also make sure that SNAP is checked in the view menu as well as GUIDES, LAYERS, and DOCUMENT BOUNDS in the SNAP TO submenu. With all that done, you'll easily see the center of the circle and if you click close enough to the center, the end of the gradient will snap to the center.

Then, once you have one circle made on its own layer. Instead of doing all that again, just duplicate the layer as many times as you need and position them. You can duplicate a layer by dragging the selected layer down to the new layer icon at the bottom of the layers palette.

--Racc

[doonee]

right on, racc
thanks a lot for starting me up here ....

d