'tricky' stamp? - try awhile then forget about it

brookefox · 24 Mar 2012, 22:45

I've been working pretty hard for two days to get a road stamped on real terrain. No luck, just a lot of re-dos. Here are a couple of pics, by no means the only kind of errors that have appeared. Whether the stamp is grouped or ungrouped, has vertical faces included or not. I feel so disenchanted that I'm not going to fully explain unless someone thinks I'm doing something wrong, can help, or has had similar experiences or something to share about this. Breaking the job down into multiple jobs to eliminate any loops works better but then there is the overwhelming task of matching the displacements since SU gives no way of specifying it, and should, or it should at least give a way of matching or repeating it.

mitcorb · 25 Mar 2012, 02:52

Brooke:
I am not sure with the images what the difficulty is. I tried stamp and drape on a regular TIN using both a flat face curvy "road" and one with thickness and compound curve(left right and up down) Could the complexity of faces in your terrain maybe have something to do with it? Am I just not understanding the problem? Or, are you stamping/ draping sections of terrain to a base map?

Gaieus · 25 Mar 2012, 08:04

Brooke: that terrain mesh looks awful. Too long and thin facets therefore any kind of further manipulation will inevitably result in some even more awful appearance. I'd suggest "processing" it with terrain reshaper first: http://forums.sketchucation.com/viewtopic.php?t=11320 then you get a much nicer distributed TIN which can then be manipulated much easier.

mitcorb · 25 Mar 2012, 13:14

But, Gaieus:
Notice the last post in the Reshaper thread you linked. Brooke has already been there, back on the 18th.
I suspect part of the problem is the size of the portion being processed by the Stamp tool. In my experiment, I noticed a delay at about 75% in the progress bar at the bottom of the screen.

Gaieus · 25 Mar 2012, 13:59

No, I did not go through all the 18 pages.

(In fact, sometimes I also have issues with this plugin...)

brookefox · 26 Mar 2012, 22:47

@unknownuser said:

Brooke: that terrain mesh looks awful.

You have got your nerve, mister no-more-mister-nice guy.

The terrain is large and flat (600 acres; 50 feet Z) and was an unmanipulated result from sandboxing the contours. As can be seen in the first pic posted earlier, the redline offset does not include the subsequently erroneously shaped area within the loop. The contours were simplified in order to reduce the size of the result; without simplification I think the results would have been worse: longer, thinner triangles. I certainly agree they are not much to look at but that's what is produced with distant shallow contours, it seems. I had tried terrain reshaper but, as I recall, it resulted in large flat areas with a border of TINs near the contours; not smooth.

Thank you both for trying to help. Sniff...

Try these views, please. No road stamp, just drape (but the tannin rich creek was stamped previously; no loops, etc. there).

(How about that Component Sprayer!)

mitcorb · 27 Mar 2012, 01:05

Hi, Brooke:
All I can say is wow. I have not tried anything of this scale or scope--yet. I confess I still am not sure what the difficulty was.

Gaieus · 27 Mar 2012, 11:06

@brookefox said:

You have got your nerve, mister no-more-mister-nice guy.

What I meant by that was that a terrain with lots of very long and narrow triangles is very hard to work with nicely. Also that's why I suggested terrain reshaper as that would ("ideally" )create more evenly distributed triangles.

That third (top) view with hidden geometry looks nice though. That's much evenly distributed than what I could see from that side view earlier.

brookefox · 27 Mar 2012, 15:51

@gaieus said:

What I meant by that was that a terrain with lots of very long and narrow triangles is very hard to work with nicely. Also that's why I suggested terrain reshaper as that would ("ideally" )create more evenly distributed triangles.

That third (top) view with hidden geometry looks nice though. That's much evenly distributed than what I could see from that side view earlier.

I thought I knew what you meant, but on second thought... The long and thins were what 'stamp' produced. They were not a part of the original terrain, which is what you are now calling 'nice'. Fickle you! Please see my initial post: the original terrain is there as displayed hidden below the floating road in the upper, 'before' image. The image below that is the resulting stamp with the 'long and thins' (that I think you thought were my original). It is likely that I should have been more clear about those images.

That is the problem, Tim: 'stamp' just botched the thing badly. At least that is my story.

mitcorb · 27 Mar 2012, 18:42

Well, the problem with drape for me was all the triangulation in the drape skinning where the road rose either above or below the adjacent sculpted terrain, and the vertices in the drape did not coincide in the least with the vertices in the terrain.