shadow bug

[bitkar]

hey, gentleman, never noticed it before.... do you get the same bug? tS7.61B8 vray1.5.3

If i put a bumpmap on it, it will make this bad quality shadow! why? do you know the bug, is there a workaround?

just put a bumpmap on any object and turn on shadows on any type of light to see it.

The problem is selfshadow casting. Casting shadow on other objects is ok. strange

[bitkar]

hm, seems like negative amp parameter on bump map solves the problem...although on the test scene I saw some artefacts on the edge of object, not too visible usually. worse is that the material looks a different then. :( shading looks strange.

anyone has another solution? is there a way to fix it? some patch or something?
this bug makes vray almost useless :( if one cant use bump on a rounded objects...

[Steinie]

Did you have the default spotlights on the object?
Try removing them and try an infinite light to see if it goes away.
If it corrected the problem, then create a new spotlight.

[bitkar]

I already tried infinite and spot light so far, (maybe I could try area light), shaders, bumps, set ON/OFF different switches on lights, rendering, whatever. This problem is not accidental. It occurs always I set rounded object with bump map (that has set shadow casting and recieving on) and light it up with a "non-area" light (or a light that cast sharp shadows). It obviously has problem with casting shadows on near 90 degree angle surfaces or something. So rounded objects are shaded very badly as you could see.

anyone has older tS7.5 with older vray1.5.2? has it got the same problem?

its a serious problem for me, as I need to use vray with "project dologran" iam working on. iam going crazy.

[marcel]

It is not a problem of vray. Lightworks do the same result with small sphere+ low poly+smooth aspect that receive shadow from a ray light. Not this problem with a map shadow. It is a bug of TS since the begin of Caligari

[bitkar]

It is not a problem of vray. Lightworks do the same result with small sphere+ low poly+smooth aspect that receive shadow from a ray light. Not this problem with a map shadow. It is a bug of TS since the begin of Caligari :)

well... i see you are right (i didnt see that when i checked the lw rendering for this, coz def. shadows are mapped :-/

thats a crap! iam damned.

btw: its not related to polycount too much... the sphere is not a lowpoly.

-----

seems like i will have to use LW and mapped shadows or HDRi lighting or very soft area light could also work to hide this bug. I was making some tests with lw only (coz iam at work and i dont have vray here, i need to test it home with vray). I hope i can find a good solution. Damn caligari for not repairing this bug. I dont get it, it cost money those days - paying for this bug is no good.

[bitkar]

btw: i tried a tS3.2 and the shadow bug is not there :D seems like i have to do it in ts3.2 :))) omg :(

[bitkar]

iam really down... discouraged, motivation is gone, totally down. I tried different things, but its just not as good as it should be. Mapped shadows just dont look good. Adding a skylight or IBL in LW for nice soft "GI-like" shadows makes the rendering time insane.

there is no way forward, and no way back...

[marcel]

Don't be worry. we find allways a way to do what we need.
When you smooth the surface of an object during the render (not with hight numbers of polys) the soft create interpolation between the faces. It seem the bug don't smooth the face that have the limit of the shadow that pass on it. the only solution to reduce the bad effect is to have more faces.
Another limitation of the render is the refraction on the face with a glass shader. the refraction is not smooted and a glass bottle need a lot of face for a good render. it is why i use quad and sds technic or nurbs (not in TS, nurbs are very bad to edit on TS).

[bitkar]

marcel: I use SDS almost all the time, its great flexible way to do smooth objects. My characters (dologran) are made from SDS and no mater how hight the polygon count is, the shadows are really bad with bump map. Without its ok. I use GI for soft shadows and spot for ray hard shadows, even better with smooth shadows ON. This lightsetup is great, everything looks good, but I cannot use it.

Iam not sure what you mean "smooth during rendering" and "interpolation between faces" ... "you mean smooth quad divide" tool?

and "It seem the bug don't smooth the face that have the limit of the shadow that pass on it." --- i dont get this one either.

Can you explain more what you mean?

btw: if I put llloots of faces on the object, so its really smooth, it sometimes doesnt have any effect, sometimes it makes the bug show less.

check out this sphere. On both its still visible, with bump its harsh, it has 12032 faces: (i will try a 2048x2048 bump map, maybe it can smooth it)