Round shapes too expensive?

[Francois]

It was to be expected that I'd turn up here with questions, right!? Right!

So I made a nice Nissen hut, you know, one of these WW2 corrugated steel huts, looking like a cylinder buried halfway in the ground.

Now, SketchUp lets you neatly plaster your photos on its surfaces.
Oops... FLAT surfaces!
And now I have a round one..... which ultimately is made up of 12 flat strips in this case.
Soooo..... it won't accept my 1 photo (featuring both sides of the hut). That means I had to make 12 separate photo strips that I craftily arranged upon the surface.

And it LOOKS good... but...

Does this mean I now have draw calls for 12 +2 photos instead of 1 +2 !? That will make a dent in performance o FSX, right?

Question: Is there a better way to do it with SketchUp or should I use Gmax after all for round shapes ????

Inquisitive minds want to know......

 

[arno]

Hi Francois,

In SketchUp you can determine how many faces your rounded surfuce gets. Having 12 is certainly not too much, so that won't be too expensive. But that was not your question.

Also in SketchUp you can apply the same material on all 12 segments. So that means only one texture is used for all. Just create the material and apply it to all polygons with the paint bucket.

Making sure that the texture aligns correctly on the different faces can be a bit tricky. I feel that is a weak point of SketchUp. But it seems you already figured that out now .

Applying the texture might be a bit easier in GMax, but for the final result it does not matter. You can make objects in SketchUp that are just as good for the performance as you can in GMax.

 

[Francois]

Aha ! I didn't know about the number of faces yet... will investigate in that too.

But for the textures: I can't use the same one for all faces, because of the photo (and object). It was darker at the bottom (dirty), lighter at the top. Also a chimney on it halfway, and some plating at the top.

So yes, I can probably use one textures in more than one place, but not on all faces. I'd still have some 6 or 8 different textures. I could cheat and paste the ones fro the right also on the left, without mirroring them..... *cough*.

I'll do some more experimenting Thanks !

 

[scott967]

I think the intended approach is import an image that you place "in front of" your object and then project it onto the surface of your object. Haven't had any good luck with it myself so haven't really tried too much.

scott s.
.

 

[GaryGB]

Hi Francois:

[EDIT]
Some Sketchup references...

Specifying the number of sides for a circle:

...or an arc:

http://sketchup.google.com/support/bin/answer.py?hl=en&answer=94740


Perhaps this might also simplify texturing (applying a Material with the Paint Bucket)

onto curved surfaces made from a Circle "extruded" with the Push-Pull Tool

to make a 'Cylinder', or an Arc "extruded" to make a 'partial cylinder':


http://download.sketchup.com/OnlineDoc/gsu_mac/D-Modification_Tools/modtool-PositionTexture.htm

The section "Repositioning a Material on Hidden Geometry" explains how to work with a 1 piece texture image which one could first prepare in a graphics program so that it might wrap around a cylinder ...or over the top of a "partial cylinder" (ex: a curved roof surface).
[END_EDIT]


PS: While working, one can check on a project's complexity via:

Sketchup Menu > Window > Model Info (...select "Statistics" and "Entire Model" with "Show Nested Components" checked)


Hope this helps !

GaryGB

 

[arno]

Hi Francois,

If you are really concerned about performance, you can probably best try to combine all the texture elements on one big sheet later on. That will keep the drawcalls down.

In SketchUp you can still use the different textures, if that makes the mapping easier. ModelConverterX can combine them in one sheet for you.

Or the other approach is to design the combined sheet by hand and then map the right element on each polygon.

As mentioned by Scott, I never had a lot of success with projecting the photo as a texture. It seems just to hard to get a clean photo of any object and from any angle.

 

[Francois]

May thanks for all the reactions. I'll do some more reading Gary
And yes, Scott, I also did the 'draw-after-photo thing once (with the first object I made this summer, our house. It worked, but isn't easy !

And yes, I saw (and used) your explanation of putting textures on one 'sheet', Arno. That works in many cases.... but not always I think. Wouldn't I run into quality (i.e. resolution) problems sometimes when having to reduce the size of (partial) textures so much?

I.e. take a LARGE building as example, with many different parts that need to be textured. If I would put all the bits and pieces on one 1024x1024 sheet, it would mean that individual parts would become really small, and would have to be extended over the model again, thereby losing detail?

Or maybe I am totally wrong in that assumption. More experimenting today !

 

[arno]

Hi Francois,

I normally choose one resolution for my building and then I make sure that all texture elements are designed at that resolution. So for a tall building that might mean you have to divide it into a few segments, because it will not fit on the sheet at once.

 

[Francois]

Understood ! Thanks

 

[Sidney Schwartz]

Projecting a material onto an object is explained on page 231 of the manual. It works, and it's the easiest way to do what you want. There's also a "Wrapping Material Around Corners" procedure that looks like it would accomplish the same thing, but with many more steps. I haven't tried that one.

 

[Francois]

Hi Sidney.
Manual !!!???? I am wrestling through the online help .... 'search' ... all the time.

Ah, you mean the Version 7 pdf manual... there's an idea. I threw it away together with my old version, assuming 8 would have a new one. Not.

Looked it up, and yes, that's what I've been doing. Importing and repositioning images.

But here's a laugh for all of you following my adventures..... yesterday I spent most of the day constructing a new building and fabricating a 1024x1024 texture sheet with all bits and pieces of images on it.

Then last night I tried to apply those bits of wall and ornaments. But.... each time I 'stuck' it on the model, the wall became transparent !!!!

I turned off the PC in disgust after having tried from 7 to 10 pm last night.

And then, when laying in bed and still mulling over this (it worked fine few days earlier), it suddenly came to me. By default I have my layered photo tool set to 'transparent background'. So the new images were on a transparent sheet... and as we use the entire sheet to stick on the model, before repositioning, I was looking right through it.

So now I know that the 'wall' becomes 'image' in SketchUp and that it is not a layer (image) sticking onto another layer (wall).

Alright, for more laughs, join me later tonight. I am sure I'll step into another quagmire today....