Slowly getting the hang of Blender, now having issues getting the results into Poser.

Created a nice profiled piece, rendered in Blender just fine (in both Blender Render and Cycles), exported as .obj.

I've figured the correct export scales and such to bring it in to Poser properly scaled and oriented, but I'm getting ghost edges in places that get filled by the materials. It's like the material is being placed on something that isn't there.

The image below shows the profile as wireframe and as it appears in the preview window (renders the same), with the offending additions circled...

any clues as to what is happening? I've tried exporting with default settings, all sorts of variations both on export and import and always the same.

Cheers.

Looks like edges were added between several verts and polys resulted, can't really tell unless you show a true wireframe with verts and edges visible. Just a guess, hard to tell. Also that object as is won't render properly in poser (smoothing artifacts) unless you add some edge loops or control edges. Is it manifold or one sided geometry? I.e. is it a closed surface or a deformed plane? if it's a plane than disregard the smoothing comment.

Additionally notice how your contours and edges are being oversmoothed? This can be resolved either by lowering the crease angle, disabling smoothing, or, as stated above, adding more parallel edges close to each contour corner.

Thanks for that, I'll look into your suggestions. I'm guessing that Poser doesn't like ngons? It is closed (not a deformed plane), but the end faces are single faces...

That was it, cheers! The end faces needed added lines connecting a few vertices and breaking up a complex area. I also reduced the crease angle to 40 and it renders fine now!

That's typical behaviour for a complex Ngon with concave edges. Unless you particularly need a face there, the easiest fix is just to delete it, otherwise chop it up into smaller areas to get rid of the concave boundaries.

Chopped it up... knife tool is wonderful! I've had too many problems in the past rendering with IDL and light leakage through non closed objects, that it was pretty much automatic to close it. Still, early days; that was my first real success getting something done in Blender and into Poser.

This is a good little tutorial about modelling for Poser that details dealing with ngons.

http://www.renderosity.com/mod/bcs/modelling-for-poser/82834/

That's funny... I have that! I bought it long before I knew how to do any modelling, then put it away for 'future reference' then promptly forgot about it... re-reading it now. Thanks for the reminder!

I don't see any ngons in the wireframe.

The problem appears to be entirely due to smooth shading and not because of the geometry. This is a known issue for Poser and modelers creating for Poser MUST either model directly for it, including chamfers and additional edges so that smooth shading calcs don't distort limited geometry, or they must adjust the smooth shading effects for their objects, manually, once inside of Poser.

It is more desirable, by far, to model specifically for Poser and to take that into account when modeling low-poly inorganic objects, specifically, even those that may have some smooth transformation in their topology. That means that, for Poser-specific models, models will generally have more edges/faces than necessary for renderers other than Firefly, which is specifically targeted towards rendering organic shapes very well, but inorganic ones (like boxes, flat objects, sharp-edged objects, not so well.

There used to be a submission guide around here that concerned the standards that .obj models must adhere to. In short - Chamfered edges, all quads, no ngons, limited stars/diamonds, etc.. are the norm. At least, what "should" be paid attention to in an object modeled for use in Poser/Firefly.

It's worth doing a google to see, exactly, how smooth shading works so that you can create models that will not exhibit smooth shading artifacts under normal rendering conditions. When modeling for Poser and when in doubt, the solution is always "more polys... " :) (Especially near sharp edges, so the shading calcs have enough info and aren't limited by single calcs across such a large distance.)

PS - Instead of chamfering those edges, which isn't desirable in this model, you can use what some refer to as "guide edges", specifically added so that smooth shading algorithms have enough verts to calc to render a hard edge that is not distorted. (Add another two edges, very close to the "sharp edges", for instance, and you may also wish to add additional edges down the length of the model so you don't get smooth-shading "buckling" at certain spots where calcs become useless, since there's no new geometry to correct them.) Granted, however, it is difficult to get Firefly to render hard edges without doing what would normally be considered as over-inflating the geometry of a particular model. BUT, if one wants something that works just fine with smooth shading, right out of the box, without additional user fiddling-with for users of Poser/Firefly, this is just what you have to do.

The end face had 17 edges. I think that qualifies as an ngon. The image I posted was hidden wireframe to show just the profile, whereas I probably should have shown the full wireframe and verts. Most of what you said, Morkonan,is included in that tutorial package mentioned by kljpmsd, including a very good section on smoothing and crease angles. Thanks for the input, though. Just starting out is the best time to avoid bad habits...

The end face had 17 edges. I think that qualifies as an ngon.

Ah. :) But, that "depends", really. Seventeen edges? How in the world did that happen? Was this a boolean-generated object? A .ai generated object? Or... user error? :D Anyway, glad you sorted it out. As it stood, as shown in the somewhat "hidden wireframe" (kind of a wire at any rate) render, if it was constructed like that, then a few extra edges and, perhaps, chamfers long the long-side, would probably take care of the shading issue.

It was a boolean cut... but as I didn't then divide the resulting face up I guess it also qualifies as user error ;-)

It was a boolean cut... but as I didn't then divide the resulting face up I guess it also qualifies as user error ;-)

No, it wasn't due to "user error."

It was due to ... "boolean cut." :)

Boolean operations are teh Evil... They almost always make a hash out of the topology. Generally, boolean operations in most modelers don't care a bit about topology - They'll massacre everything to achieve the operation, which is usually counterproductive. Booleans in certain very nice modeling packages can do a much better job, sometimes requiring a few different fine-tuning operations, but...

By far, if you have a choice, choose to do the shape by hand rather than use a boolean operation to do it. Unless your program can help you retopo the object or has some sort of nifty "smart boolean" (NO SUCH THING! ;) ) you will always get better results forming the object by hand. Always.

Yes, boolean operations seem to be there to be a general helper for the modeler. But, that is wrong...

The Boolean is a lie!

;)

(Note: Achieving the shape you produced can be done other ways than polygon modeling strictly from scratch. For instance, some 3D modelers allow you to import Adobe Illustrator files (.ai) and other vector image formats. These will generally be imported as "line art" types of volumeless models. (2D Lines) From bases such as these, you could do a simple extrusion to achieve the shape derived from a pattern of curves you created in a 2D application. Also, some modelers have internal "line" tools which let you create the very same sort of objects, suitable for the same sort of extrusion operations. Some of them could even be dynamic, allowing you to change the shape of the extrusion on the fly, simply by manipulating the curve it was derived from.)

Yep. Haven't got up to the line and extrude method yet, but have already collected a very nice set of profiles in line form. Boolean seemed the easiest way to get a true 45 degree cut in a modified box (although I could have angled the face to 45 degrees before profiling, but if I wanted angles to go in all directions I started with a straight section then cut them at the required angles). I also used boolean to create a joined geometry, but after the first experience with it in Poser, I went back and altered some of the faces. Works much better now (no long triangles!).

Having said that, I'm most probably going with the extrude line option. I have also now learned how to turn the straight section through 90 degrees with no 'caps' (so doing what line and extrude does). For curved sections of walls, the line and extrude option is probably the only practical way.

It sounds like you're progressing pretty fast with Blender! Congrats! Every time I look at the latest release, I throw up a little in my mouth... :) But, hey, if it works for you, that's all that matters! (I am sure I'm going to have to learn it, one day. /sigh)

Something to note: If Blender has a good retopo tool, you might be able to get away with a Boolean operation and end up with some topology you can tweak to be suitable.

Ah, found it: http://wiki.blender.org/index.php/Doc:2.4/Manual/Modeling/Meshes/Editing/Retopo

Seems like they're putting everything in Blender. When it can change my oil and balance my checkbook, I might try to learn it. :)

Happy vert pushing!

Cheers, and there is a push to have the interface simplified and standardised so people can still find things. I have the advantage of never getting comfortable with other packages; played with Max, Lightwave, Hexagon, then Blender. All have different UI's, so Blender was just a variation, not 'alien'. Despite that, I'd vote for a more consistent layout between versions. 

I've seen the retopo stuff, but haven't got anywhere near that yet.