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Jykke
08-20-2009, 05:23 AM
For some reason it's very hard to get the camera angles etc. just right so the terrain is usable as a map. Sometimes the top view doesn't work and you have to tilt the camera angle to get the mountain shape to show. The problem here is how to make a 3d mountain that has the shape feel to it, and still be able to have that overview type of map.

Just to demonstrate it (or atleast trying to demonstrate), I've rendered few images of the same terrain from couple of different angles.

First one is the side view (mountain profile)
Second one is the top view
Third one is the tilted view

Any thoughts on this issue? :S

Jykke
08-20-2009, 05:27 AM
Oh, and I must post the lyrics of the song I listened while doing this :D

Amorphis - Skyforger

Inside this nonexistence
I know very clearly
The directions, all the points
Of every potential quarter

I forge my wisdom
Into an arc surrounding all
I forge my heartbeat
To a dome all heavens wide

I know the sun and the moon
The names of stars
Their movement and purpose
I mark the place of polaris on these impossible heights

I forge the horizons
I craft them for flowing blood
I forge the places
Precise for silver, precise for gold

In solitude, I measure out
The range of barren lands
I drain unto the nothingness
The intersecting curves
I look at all directions
I look at one clear point
I see them all come together
I see into the heart

This here is my place, it is my work
I was made the maker of the sky

I am the maker of the sky
I am the forger of the arc

Coyotemax
08-20-2009, 05:28 AM
top isn't bad, but I kind of like the 3rd one. it's enough of an angle you can see the mountain shape and the shadow brings it out, but not so low you can't see things in behind it, as a proper map :) if that's the steepest it gets, you wouldn't find much in the way of mappable features on that section anyhow (unless you're mapping out ski areas, then i'd go for the first view anyhow)

Jykke
08-20-2009, 05:45 AM
yeah, tilting the camera makes it look better, though it brings the issues of perspective. Isolike perspective might solve almost all the issues, but I'm not totally sure how to get it work with vue.. Maybe zooming the camera all the way back might produce this kind of effect?

Steel General
08-20-2009, 07:42 AM
They are all neat images.

I know little to nothing about 3d terrain programs, but I think the problem with the second one is more of a lighting issue than anything else. *shrugs*

Jykke
08-20-2009, 08:51 AM
They are all neat images.

I know little to nothing about 3d terrain programs, but I think the problem with the second one is more of a lighting issue than anything else. *shrugs*

Thanks for the input :) I'll look into it and maybe even solve the issue. The problem with the lighting is that if it is adjusted in the wrong way, then the mountain might get flattened, or it just might look odd. Well, I hope I find just the right settings.. then I'll be able to do a whole map based on the results.

Greason Wolfe
08-20-2009, 10:53 AM
One thing you might try, and this is what I do with some of my Terragen renders, is pull the camera waaaaay back then, set my target as dead center of the map while the camera position is slightly south of dead center. This still gives a fairly good "top-down" view, but also adds just a tiny bit of isometric view as well, but, usually, not too much to grossly hide things.

As I don't know anything about Vue, I'm not sure if this is a possibility for you or not, but when I have my settings right, I've got a bit of space to work with as far as cropping things out to be nice and square.

GW

Jykke
08-20-2009, 12:06 PM
same terrain, no trees, and a viewpoint similar to Greason Wolfe suggested.

Ascension
08-20-2009, 01:24 PM
I think that you've got it there. Looks pretty good.

Jykke
08-20-2009, 01:34 PM
I think that you've got it there. Looks pretty good.

I hope this is it :). It might be fun to be able to use this in an actual map. Thanks for the feedback!

Oh, and here's a final render with some trees (actually if I render the whole scene, there would be ~900 000 of them).

If there is more suggestions etc, I'll hear them gladly!

Greason Wolfe
08-20-2009, 02:43 PM
I think that's about got it. One thing to keep in mind, points further north in your scene will have a shallower angle of approach the further they are from the camera and target positions, so it may still come to pass that some things at the extreme northern edge of the scene, as a whole, may end up being partially hidden by mountains and such. This, of course, depends on how much area you are rendering and how high above the land the camera is.

GW

Jykke
08-20-2009, 02:47 PM
yeah, I might have to sling the camera all the way to the earth orbit :D to get the whole scene area to show just the right way. I did a new scene trying to emulate longer mountain ranges.. just to see how it would look like. Will post the picture when the rendering is complete.

Greason Wolfe
08-20-2009, 03:04 PM
Naw, you won't need full orbital distance, just a low orbit. :lol: As an example, to get the full "world" render for my Hearthstone map, I have to set the camera elevation at about 130 miles above the surface for an area that is 175 by 175 miles, or roughly three quarters of the average width and height of the area in question. Of course, depending on zoom levels, this can vary to some degree, but you probably get the idea.

GW

waldronate
08-20-2009, 03:44 PM
I recommend the techniques at http://www.shadedrelief.com/ specifically http://www.shadedrelief.com/plan_oblique/plan_oblique.pdf for further reading. I used the project/unproject technique for my march 2009 challenge entry ( http://www.cartographersguild.com/showthread.php?t=4676 ) and the silly Turtellaria map ( http://www.cartographersguild.com/showthread.php?t=6382 ).

One of the things on my list is to add a non-photorealistic renderer to one of my projects and do 3D orthographic or perspective with suggestive contours. Or even just edge-detecting on the Z-buffer to bring out the edges of the mountains. That way mountintops don't get lost in the distance as easily. Photorealistic rendering is fun and all, but I hear lots of whining from folks who claim "that's just math, it's not Art."

Jykke
08-20-2009, 04:01 PM
Some of us are "artistically" talented.. others need proper tools to project their vision. :) Here's a fresh render of a projection:

Jykke
08-20-2009, 04:49 PM
I recommend the techniques at http://www.shadedrelief.com/ specifically http://www.shadedrelief.com/plan_oblique/plan_oblique.pdf for further reading. I used the project/unproject technique for my march 2009 challenge entry ( http://www.cartographersguild.com/showthread.php?t=4676 ) and the silly Turtellaria map ( http://www.cartographersguild.com/showthread.php?t=6382 ).

One of the things on my list is to add a non-photorealistic renderer to one of my projects and do 3D orthographic or perspective with suggestive contours. Or even just edge-detecting on the Z-buffer to bring out the edges of the mountains. That way mountintops don't get lost in the distance as easily. Photorealistic rendering is fun and all, but I hear lots of whining from folks who claim "that's just math, it's not Art."
There might be some 'racism' towards 3D mapping. Or atleast there is generally more interest when raster graphics is used in a map. Migh be just a hunch..

Tear
08-20-2009, 06:55 PM
There might be some 'racism' towards 3D mapping.

There is? I, personally, enjoy a good hand-inked map just as much as a rendered beauty. It's all about atmosphere for me. Different mediums produce different feelings in a viewer.

A rendered map might not get as much nostalgic and antiquity juices going as a hand-drawn one, but it often excels in terms of detail and sheer wow-factor, so both have their applications.

Just my opinion.

Hai-Etlik
08-20-2009, 09:07 PM
It sounds like you want an oblique projection with a projection plane parallel to the ground.

http://en.wikipedia.org/wiki/Oblique_projection

RobA
08-20-2009, 09:11 PM
Take a look here:

http://www.cartographersguild.com/showthread.php?t=1046

-Rob A>

Jykke
08-21-2009, 02:38 AM
Hai-Etlik, I'm not sure if the application I'm using (vue) enables me to do the type of projections etc you have mentioned. :S

RobA, there might be some problems as I don't use a single texture map on the terrain.. and I actually have some functions running that depend on the heightfield etc.. Though I might be able to render a flat looking terrain to get the "overall" texture of the scene, It still might prove to be a bit tricky to get it aligned & stretched to fit the heightfield on another program.. So I'm basically looking just a way to set the camera right, if that is possible in some way. :D

Tear, You may be just right about that. :)

Jykke
08-21-2009, 05:22 AM
This camera angle is probably a bit too low, but it shows the type of effect I woud want on a larger map.

Hai-Etlik
08-21-2009, 08:26 AM
Hai-Etlik, I'm not sure if the application I'm using (vue) enables me to do the type of projections etc you have mentioned. :S

You could simulate it with an orthographic projection and then using a height map as a displacement map.

Here's an example. Orthographic on the left, simulated oblique on the right.

16109

It'd probably just wreck your pretty picture, but it's worth a try. Getting proper oblique projection would work far better if you can convince the software to do it, or if you can export data into some other software that can.

PS:

Re: RobA's method. Just use the orthographic image as is, with lighting and all. Then use only ambient lighting in POV-Ray.

waldronate
08-22-2009, 03:55 AM
You can pseudo-project an image back from a 3D view to get a 2D view using the perspective and scale tools in Photoshop. The attached images show a trivial example in Wilbur.

The first one is a basic 2D image generated from a height field.

The next one is the height field and image from the first step in Wilbur's 3D viewer. The 2D distortion will eat a lot of resolution in the squished part of the image so I stretched the window to get it as large as possible. With a real 3D app you can render to a large resolution. (I overdid the 3D angle a bit so it's a little overtall for the mountains.)

The final one is the middle image pulled into Photoshop and some basic processing done to it. I applied the perspective filter to pull the top of the image out until the sides were vertical. Then I used the scale operation to stretch the perspective-distorted image back to its original square proportions.

This process gives you something like plan oblique relief from a generic 3D app with no need for special projections. It works better if you can put a bit of a horizontal barrel gradient into the height field before you render it. These techniques are from Tom Patterson's discussion at his web site (the http://www.shadedrelief.com site and http://www.shadedrelief.com/dem/dem.html ).

Jykke
08-22-2009, 04:48 AM
Ok, I'll have to take some time and test these techniques out. Thanks for the advice :)