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with 1.0 I have a strange phenomenon: even with a simple triangulated object there are parts of triangles (not even whole triangles) that are rendered black, and unrelated to shadow casting.
below a simple example (the middle one is MWR) and a quick render of my current project, where the grass (consisting of 1 triangulated object) and the sides of the concrete stairs (which is a rectangle divided in 2 triangles) are partly black. for the purple star, there is no material defined, just the default fz color. the grass is an image map.

any clues?

tnx
wim

Could be a bad geometry. Did you triangulate all faces?

Maybe try to reload the geometry with the new reload button.

I had this in beta and RC and it was always due to bad geometries/non triangulations or reverse directions

it is not bad geometry, I know that trap. the star is a one click generated object directly from formz, with the star function. and the grass rendered well in rc5

wim

wimver wrote:with 1.0 I have a strange phenomenon: even with a simple triangulated object there are parts of triangles (not even whole triangles) that are rendered black, and unrelated to shadow casting.
below a simple example (the middle one is MWR) and a quick render of my current project, where the grass (consisting of 1 triangulated object) and the sides of the concrete stairs (which is a rectangle divided in 2 triangles) are partly black. for the purple star, there is no material defined, just the default fz color. the grass is an image map.

any clues?

tnx
wim

...

could be a smoothing/ normals issue. did you try to recalculate normals in studio? maybe you should send the file to NL tech support.

markus

Hi Wim,

I have encountered the same problem. These black triangles seem to appear only with diagonal objects in my render. Plain extruded objects (cubes etc.), nurbs and free forms don't have such a problem.

I don't think it is an issue with the normals as it only affects a part of the object and not the entire object.

can any of you do this simple 1 minute test:

open a new doc in fz, draw a star with the star tool (any size or param setting will do) with a plain color, and then hit render?



this is what I did in the image above. the star object is only made of triangles, so no triangulation issue. also the normals all point outwards.
If any of you can reproduce this, it is obviously a NL matter, else I must check my configuration or reinstall.

here are 2 MWR screenshots with the normals on:




tnx
wim

Hi Wim,

Did the test for you and I have a similar result. I suspected previously, that it might have to do with the way formZ defines geometries (which is of course very different from all other 3d modellers). All my diagonal objects have the same problem. But I am not an expert. Maybe NL/Juan should investigate this.

I find if the "scenescale" is set to anythign other than
0.01 then black areas appear in my render.

We are investigating it just now. The problem is regardless the order of the vertex that define each triangle. Theorycally MaxwellZ does not need to know which sort of geometry is being rendered, it just ask formZ api for the list of vertex, the tessellation is done in the formZ side. So MAxwell does not know if the order is right, it seems to work in most of the cases but not in all of them. We are working on it just now, I hope we can do something in our side. Although some features will not come until formZ 6 is avalaible, we can try to fix others meanwhile. We have put all our efforts in the integration of the material editor inside plugins and now we can be focused in this other issues.

Regards,

Juan

Thanks guys,
at least I know it has nothing to do with the installation.
too bad I have to go back to RC5 now..... I already calculated new rendertimings for my customers while I thought to have the architectural glass available ... my mistake.

thanks Juan for taking care of it. I put all my hope on you!

cheers
wim

wimver wrote: too bad I have to go back to RC5 now.....

But do you get the same issue with RC5 or this only with RC1?
We are trying to know what is happening here. If you want you can send us to maxwelltech@nextlimit.com a little scene that reproduces that undesired behavior (apart from the star primitive, which I am investigating now). If the scene is too big you can send me a private message to look for another way to download it.

Regards,

Juan

Juan,

the scene with the appartments rendered just fine with RC5. so did all the other stuff I produced so far.

I will send you the grass only, that is not too big.
thanks
wim

Hi wimber,
It will be incredible useful if you also send us a mxs file of the grass with both RC5 and 1.0.
Thank you very much!

Juan