I’d dearly love to see this…

Richard,

Yeah, that’s what it looks like it’s doing. I’ve tested it with BMPs in greyscale, paletted-256, and 24-bit colors.

If I use the same source image for multiple tiles, the tiles match perfectly. If the subsequent images, however, have a different height spread, it ends up being slightly off.

I don’t think this is something that can be andquot;fixedandquot;, because your heightmapping algorithms are very accurate and work exactly as they should. And you know what they say….if it ain’t broke, don’t fix it <!– s:) –><img src="{SMILIES_PATH}/icon_e_smile.gif" alt="" title="Smile" /><!– s:) –>

The only practical way to achieve the effect I want would be to accept a single heightmap, have the user choose a andquot;grid sizeandquot; like 4×4, 8×8, or whatever, and then output the correct number of andquot;tilesandquot; as separate objects. But I personally think that’s too much work for a dubious gain (it’s a left-field and rather niche request, after all), so I wouldn’t worry about it if I were you.

On the bright side, I’ve been getting wonderful results with the Deform tool. I’ve made a fairly convincing mountain range with it on a face subdivided several times. If I have time, I may be able to do a tutorial on using the Deform tool to create terrain.

-Mel Ebbles

I’ve been playing around with the terrain tools, and I’ve found a couple of real annoying things that I don’t know how to deal with.

If I take a large heightmap and then split it into smaller images for importing into 3DC, none of the generated terrain objects will exactly match up. There’s always some margin of error in the Y values. This is unavoidable, really…but I wish I could stitch them together without actually attaching them to each other permanently.

This is for a realtime application, so having a single humongously massive uberterrain with an umpzillion polygons is way out of the question.

So, got any ideas on how I can:

1. Split a large terrain into smaller tiles without 8 hours of ctrl-clicking faces, then cutting and pasting;

-or-

2. Stitch several smaller terrains together in such a manner that they are still separate geometries, but precisely aligned along the andquot;seamsandquot;?

-Mel Ebbles

Mel,

Actually, I meant that I mirrored the texture itself in andquot;paintandquot; and it matched up fine. Based on what I know about how the program works, equal colors should match up. So… I would guess that means you don’t have exactly equal colors for some reason.

Richard

Mel,

I tested this and my mirrored heightmap did match up OK. Did you mirror your height map? As long as the pixels along the edges are identical from one map to another it should link OK (but I could be wrong).

Alan,

Export a height map? In what way? Create a bitmap from a fractal terrain object?

Richard

Master,

form memory, not to good, you can import into the terrain tools at 200X200 ? Could you not reduce your height map down to this, create your terrain (maybe at a higher quality) and then stretch it out afterwards ? Or would you loose too much quality in your map ?

On the subject of the terrain tool – any chance of been able to export a height map from it, Richard ? (Might add this to wish list for v6 )

Half expect an answer that your height map is 1024*768…….still might be worth a try ?

andquot;Grasshopperandquot;

Grasshopper,

As usual, you catch on rapidly. I can indeed reduce and import a 200×200 heightmap and still preserve a lot of quality.

Heightmaps of that size look very, very sweet as 3D terrains. My problem is the fact I’m working on a flight sim for my cute little airplane, and I have to support users with lousy video cards. (like me, max texture size is 256×256 for my accursed Voodoo 3 3000, which I incidentally bought THREE WEEKS before 3dfx announced they were folding like a cheap TV table. Aren’t I a genius? LOL). And there’s a large number of people with cards just like it, and I don’t want to exclude them from the andquot;marketandquot;.

So I have to either tile the same texture across the whole terrain, which is painless but kinda boring to look at. Or I can just cover it with one 256×256 texture, which starts looking pretty bad when you scale the terrain up to, say, 8000x800x8000 units.

Or I can paint a single large terrain texture and slice it into 256×256 sections, and manually paint them onto the corresponding regions in 3DC, which would look very good, but the idea of manually selecting, like, 32,000 faces kinda scares me. Plus having the game engine processing 32,000 faces 30 times a second when 3/4ths of them are actually out of view just seems a criminal waste of processing power.

What I’d really love is some sort of utility or plugin that could unlink the faces of a single terrain object into several smaller tiles, each being in its own group. Then I can use one heightmap, run the plugin on the object, and end up with a nicely sliced terrain ready for use in a flight sim. Then in the game, I can hide/unhide sections of the overall andquot;worldandquot; based on camera distance, keeping the visible polycount to a manageable level. Unfortunately, I don’t have Visual Studio installed anymore and the CD’s shot. So that notional 3DC plugin is just a pipe dream at this point.

Richard,

Yes, the mirror tools work perfectly. What I meant was, take a 128×128 heightmap, split it into 4 64×64 images, and then import each of them into 3DC as an individual terrain object.

When you butt them together, you’ll notice that there’s some height averaging andquot;problemsandquot;, i.e., the same color value in Map 1 doesn’t necessarily translate to the same Y height in Map 2. This, from what I understand, is a normal side effect of the pixel color-to-height value sampling process.

On a side note, I love the Deform tool. I ran the Create Face plugin, executed several Divide operations on it, and used the Deform tool to make some fairly nice terrain features on the flat surface itself. I’m so happy it obeys the XYZ constraints…and I’m wondering if it would be possible to add some sort of andquot;altitudeandquot; parameter to it?

i.e., if you select 128 as the andquot;altitudeandquot;, the deform tool will only deform in a -128 to 128 unit range, with the current pixel’s XYZ location values being the andquot;0andquot; value in all three axes. It’d make the Deform tool a lot more powerful. I suppose you could add Min Extent and Max Extent input boxes to the Deform tool’s right-click popup. Workable? I know it’d make editing mirrored terrains much easier than manually eyeballing the Deform tool when making trenches and valleys.

Oh, and Alan’s heightmap-exporting idea has a lot of practical merit. Insane Software has a freeware terrain texture tool that takes a heightmap and several source textures as input, and generates a composite texture with per-pixel lighting and correct colors at varying altitudes for, say, rock/grass/sand/snow and whatnot. Being able to export a 3DC fractal terrain to a grayscale heightmap would allow people to make use of tools like that.

-Mel Ebbles

And you were using BMPs?

Richard

Nope. So much for that theory.

Doesn’t even matter if the colors in the rightmost vertical strip of pixels in the first image matches the colors in the leftmost vertical strip of pixels in the second image. The Y values on both terrains are still off by a few units along the andquot;seamandquot; where both images would meet.

I even went so far as to use the pen dropper to sample all 64 pixels on both bordering sides of the mini-heightmaps in Paint Shop Pro, and the colors matched exactly. Didn’t make a difference. So splitting heightmaps into a lot of smaller terrains isn’t feasible.

Bummer.

-Mel Ebbles

Richard,

Er, I think you’re correct. I forgot that my image splitter was probably reindexing the palettes of each subimage…and since there’s a lot of variance across the andquot;ubertextureandquot;, it stands to reason that certain squares might have more or less color variances than others. So that’d explain the mysterious height offsets, if it’s actually a 256-color palette reindexing that’s the culprit.

I’m going to experiment and see if that’s the problem. News at 11.

-Mel Ebbles

I think I know what it is. 3DC scales the result to the height indicated. If the maximum andquot;heightandquot; (color) of one is different than the other then they will be scaled differently.

Richard

Alan,

That’s not really an option at this time. Too many things on my plate. I’ll add it to andquot;the listandquot; though.

Richard

yes please – for the reason that Mel gave andnbsp;