My first real model! (WIP)

[BS-er]

I have my first real model well underway:



It is intended to be an ancient comm tower or some other such structure left behind by the previous civilization.

I used some real-world textures from http://www.cgtextures.com, with minimal touch-ups.

I manually added some darkness for ambient occlusion to the side textures below the top portion.  Still, the top portion brings up the point that we won't be able to self-shadow these models in Ogre (without some extensive rework), and therefore its best to create structures that don't reveal that limitation so much.  That's one lesson learned from this effort.

Another concern with this model is pattern repetition.  The side pieces are designed to use the same portion of the texture, in a mirrored repetition.  I hope to add some sort of pattern or decal to these sides, some sort of ornate markings.  It's fine to repeat something like that on a symetrical structure like this, but it's a bit unrealistic to have the randomness of the cement pattern be repeated too much.  Still the mirrored repetition of the patterns doesn't seem to stand out much.

With this model I am hoping to embody some preferred principles for developing models in MAD:

• Avoid blanket texture repetition in general, i.e. the simple case of tiling the full texture square over an area of the model.  This is frowned upon in professional modelling in general, unless you can effectively use multi-texturing to make the repetition less glaring.  An example is repeating floor tiles, where you use another texture or two with different UV sets to add color variations and maybe dust.
• Mirrored repetition may be suitable when done as shown above, where the repetition is done in order to repeat a pattern on different faces.  Any ornate patterns would best be symmetrical across the vertical.
• Use real-world textures to good effect, especially for older weathered structures.
• Be aware of ambient occlusion needs, and avoid shapes that reveal self-shadowing limitations (like this model)
• Keep the number of materials to a minimum.  This structure uses only two different materials.  Using many different materials and textures can have a considerable performance hit.  It's best to fit as much as you can into fewer textures.  Ideally there should be no more than 2 dedicated textures for a given model, maybe 3 tops.  Using only two materials is desirable as well, but sometimes it may be necessary or advantageous to render a texture in several different ways.

Anyway, comments and feedback are welcome.  There's still much to do before I'll be satisfied with the model.

[bigbadbogie]

Looks more like a giant concrete watertank that belongs in a farmyard.

I would add a smooth modifier to the base and mid sections to make it look more rounded.

What program did you use to make it?

[Black Manatee]

Nice.  I especially like the rust glurg dripping down from the upper level.   

A couple of comments/questions:

• How big are your texture maps (e.g. 512 square, 1024, etc.)?
• What's the difference in performance hit between high-detail texture (e.g. 2048, 4096) versus high-detail geometry (e.g. more than 10,000 or 15,000 polys)?
• I like the idea of varying your texture orientation (mirroring and/or rotating) for stuff like cement blocks--it's actually something real-world tile-layers do when using cheaper (i.e., affordable) man-made tiles and flooring.  Still, I assume you put a fair amount of effort into making your textures "tileable" in the first place (seamless repetition), as well as setting up your faces to use the different orientation.  Given that fact, you might consider creating a variant (or two) of your texture map, using the same edges but different "innards."  In other words, rather than repeating as yours does now:  xabcdxdcbaxabcdxbcdax, it would go like this: xabcdxefghxbcdaxhgfex.  That's something Tim Aste does a lot (Torque's featured artist, who does a lot of exterior structures)--except he'll tile with four variants instead of just two.  That reduces the impact of the mirroring issue--although it requires a second texture map, of course!
• Along the same lines: here's an area where you'll probably be able to figure out something that I never was able to get work--I do think that multitexturing (with multi-UV resolutions) is a great compromise between the "excessive" realism, workload, and texture-load of using all real-world textures, versus the noticeable repetitiousness of tiling real-world textures. Virtually any building surface (concrete, steel, wood, stone, paint) will look pretty realistic when a well-executed tile effect (tiled smoothly at both the X and Y edges) is combined with a translucent dirt, rust, or wear overlay.
  
  Have you discovered a way to export multitextures via Blender?  Thus far, I've only been able to map one u-v texture (and thus, one material) per face--but if I could include a second U-V texture or material on a given face, I'd be able to map it differently (e.g., 0.5 reps per wall rather than 4 reps per wall)--which would allow me to create a dirt effect, and dramatically reduce the workload required for creating buildings.  If you know how to do this, I'd love to hear how it's done!
• The top surface (the diagonal area) apparently employs a stretched version of the U-V map from the middle one-third of the cylinder.  You may want to consider two alternative approaches in order to make it less obvious: 1) Use a different portion and/or orientation from the same texture map (e.g., a bit of the red band near the top, then moving down (inverted) to include the rivets; 2) Increase your number of reps in the x-axis so that they match up with the segments at the top of the flat cylinder portion.  That way, it'll be less stretched, and it'll also feature more of a contiguous look--like the segments are continuing from the sloped area down to the vertical edge of the cylinder
• Consider using the concrete texture--perhaps just with a different material effect (ambience/diffusion/whatnot) in the script file--for the base of the top section.  Right now, the rusty drip marks fan out too much and don't look as realistic as the sides of the cylinder, because they're on a flat surface.  An alternative would be to make the x-reps higher on that surface as well, so that the segments seem to continue all the way from the oblique top down to the flat base.

[Avatar]

Well, if you can stand a bit of criticism...       you picked a bad angle to screenshot it from...  

As you say, repeating textures can quickly become noticeable, which is why so many games do what Battlezone did and create their textures in the form of large sections of the object, hand painted if you will.  This sacrifices some texture memory for the ability to differentiate large sections of the model.

In this case it's not overly apparent but if you look at the base of the tower you can see where you mirrored the UV mapping...  the top part of the concrete shaft has, to my imagination, an alien face staring out at you.   The bottom has an alien 'angel'. Both are the result of the subtle part of the texture being mirrored horizontally. This is common in many professional games also, and several similar examples can be found in Half Life, Battlezone 2, and other games I love...  There's a very large rock formation on Rend in BZ2 that looks like the face of the devil...

Anyway, other than that totally nit-picking bit of observation it's very good.  Looks a bit high poly to me but the engine smoothing plays a big part in that and it's not always easy to tell.  (remember, I'm old school and anything over 500 polys is obscenely high imho...  lol...)

-Av-

Holy crap Black Manatee must be a fast typer...    lol... 

[Black Manatee]

Kind of.  I do a lot of teaching over the web---including discussion groups with up to 15 people--so I've had to learn to be quick in order to survive! 

[BS-er]

Thanks for the honest feedback.  Criticism is actually very much needed.  Stepping away and coming back to it, I see that it does look like an odd sort of water tower, but maybe not like a futuristic/ancient structure.

I'm pleased with it as my first real model, but it reinforces what I've seen in the artist community: after working long and hard on a model, you start having trouble judging whether it is meeting its initial goal.  When you drop by the artist communities and forums, you see that they post their WIPs and other artists pick them apart, pointing out every little flaw and suggesting improvements.  Its the best thing they can do for each other actually.

The model weighs in at a whopping 278 vertices.  I hope today's hardware can handle it  .  Maybe there's a bit more room for some polys to add detail and complexity.

[OvermindDL1]

And some normal mapping to help 'round' out the bottom 3/4's of it. 

[BS-er]

Have you discovered a way to export multitextures via Blender?

I imagine that if I look hard enough I might find how Blender can export multitexturing.  I can accomplish the multitexturing after the material is exported, so its no tragedy if we can't do multitexturing in Blender.  Blender does support and export multiple UV coordinate sets.  We can write the Ogre material for multitexturing, as well as specifying which UV coord set is used for each texture.  I'll make it a point to see how much of that can be set up in Blender though.

Most of the time we'll need to hand-edit the material scripts anyway.  Blender (or Max or Softimage) serve their primary purpose by letting us form the model, link materials to faces, UV map, and add skeletons and animations.  When it comes to Ogre materials, these tools and exporters have their limits.

[BS-er]

And some normal mapping to help 'round' out the bottom 3/4's of it. 

That's if you're trying to make it look quite round.  This structure has sharp corners to its base and therefore it is correct to not smooth it with those few large polygons.  The result would be quite flawed.  Still I'm sure something is needed.  Adding more polygons for each edge would allow us to do a more realistic and correct rounding of the edges without gross shading errors.  Some more detail in the textures is needed as well I think.

[BS-er]

Actually I misunderstood you there.  I was thinking of the shading transition across the polys.  Bump mapping could improve the appearance, but I'd still like it to look good with bump mapping turned off. 

[BS-er]

What program did you use to make it?

I used Blender, which seems capable enough.  For a free program it is fairly powerful, although some aspects of the interface and GUIs are quite frustrating.

[Avatar]

I haven't seen many actual 'round' concrete objects of any real size, although using a tube for a form is quite common for smaller concrete bumpers and support pylons.  Larger concrete structures, at least in the US, are usually squared off as they're done with angular forms.

So, IOW, I think that bottom looks just fine IF it's made of concrete. 

I'll tell you how I approach something like this...  I do an internet image search for terrestrial versions of what I'm making until I find something that catches my eye.  I rough out what I want based on that, then make a few variations to see which of them 'moves' the thing in the direction I'm looking for.

In this case if whoever is supposed to have left that tower lying around is similar to some race that's around now, or been around in the past, I'd look at what that race left.  You know, check out some Mayan Temples, or Aztec Pyramids, or Czechoslovakian communications towers...   

IOW you need a muse...  mine's the internet but each must find their own...

-Av-

-Av-