Digital Art Zone

I’ve been playing a bit with this Christmas Tree:

http://www.daz3d.com/shop/yuletide-treasure-tree-2011

Excellent product as such, but there’s something I don’t understand. In the Poser preview it looks like the tree has dropped all its needles on the right side. Doesn’t matter if you rotate it, it’s the same from all angles.

Likewise, if I set up a symmetric light set, the right side of the tree is equally dark, compared to the left. I have to use a rather asymmetric light setup to make the light look somewhat evenly distributed. It only seems to affect the tree, not the props.

Anyone who knows why that is?

I’ve attached some pictures to demonstrate what I mean.

Are the needles on the tree billboards rather than geometry? I would imagine they are (I don’t have the product) and that can cause issue on how they face the camera and how light and shadow is cast.

EDIT> Not that I don’t fault the maker of the tree. All geometry would be a real system crusher. Not to mention, migraine inducing modeling.

jmper - 26 November 2012 10:19 AM

Are the needles on the tree billboards rather than geometry? I would imagine they are (I don’t have the product) and that can cause issue on how they face the camera and how light and shadow is cast.

EDIT> Not that I don’t fault the maker of the tree. All geometry would be a real system crusher. Not to mention, migraine inducing modeling.

No idea, don’t know what billboards are. But i agree, using geometry would probably be a gigantic task. In any case it’s very detailed and looks very good so I don’t complain…

I’ve attached a close up in case that may reveal something:

Does it change anything if you switch preview mode (OpenGL - SreeD or visa-versa)?  I have seen that before with transparencies. I assume it is not showing up in the render (those lower images are finished renders, right)?

Two-sided items showing odd artifacts after rendering

Does this help?

Billboards are transparent images often used to simulate foliage… a simple example would be a small square UV mapped with a leaf image on a black background… in the transparency setting poser is told NOT to render the black area… the modeler then covers the branch with many similar simple square polygons which will render out as leaves… the simple squares save resources as one does not have to model 6 billion actual leaves.

***Double post from quoting myself!

lordvicore - 26 November 2012 10:32 AM

Does it change anything if you switch preview mode (OpenGL - SreeD or visa-versa)?  I have seen that before with transparencies. I assume it is not showing up in the render (those lower images are finished renders, right)?

Well now that you mention it - I’ve just installed Poser 8 and PP 2012 in Win 7 - 64. In Poser 8 and PP 2012 - 32 the preview only works with SreeD, so I set them to use that. It seems however that this setting also affects PP 2012 - 64 (which I’m using here). I’ve now set it back to OpenGL, and this is how the preview looks now, in PP 2012 - 64. No difference in the rendered scene though, as far as I can see.

And yes, the two lower pics of the first three I posted are renders.

Wow…gone for a few minutes and the help posts floodgates open.

And looking at the picture you posted, they appear to be billboards to simulate the foliage (as lordvicore indicated). The foliage follows a similar path which would usually indicate a mapped transparency on a flat plane. Usually easier to tell if you observe it in the material room.

***GAAAH I quoted myself!

araneldon - 26 November 2012 10:36 AM

Two-sided items showing odd artifacts after rendering

Does this help?

Hmmm… thats interesting… I wonder if that is the cause of something I had a problem with once… some weird shadows that would show up in a triangulated polygon…  I googled it and never really fixed the problem and ended up redoing the part.

Since it is billboards, the only way I found to make the shadow and light look correct sometimes is to do what you did which was using a specialized light to enhance the offending side.

I really like this tree. IT renders quite well… Thanks for posting about it- although-sorry you are having trouble.

Looking at that again, it does appear to be made out of billboards… if you look on the left side some of the planes are tilted slightly to and fro.
My amateur guess is that the preview mode does not see the light interacting “properly” and perceives the whole part as transparent.

?

By the way, you are just asking why this occures (sorta like “is this normal?) and not trying to solve a problem… like you don’t actually need this to appear “normal” in preview mode for some reason… right?

araneldon - 26 November 2012 10:36 AM

Two-sided items showing odd artifacts after rendering

Does this help?

Hey, that seemed to fix it. I checked Normals Forwards for all the needle material groups I could find, and this is how it looks now, with symmetrical lights.  Thanks!

lordvicore - 26 November 2012 10:38 AM

Billboards are transparent images often used to simulate foliage… a simple example would be a small square UV mapped with a leaf image on a black background… in the transparency setting poser is told NOT to render the black area… the modeler then covers the branch with many similar simple square polygons which will render out as leaves… the simple squares save resources as one does not have to model 6 billion actual leaves.

Well here’s how it looks in the material room:

SereneNight - 26 November 2012 10:51 AM

I really like this tree. IT renders quite well… Thanks for posting about it- although-sorry you are having trouble.

Yes, it’s an excellent product - have been looking at others (Rendo had one for sale last week) but this is by far the best I’ve seen yet. And the problem is fixed now as you can see.