Batch bake gives me black textures on some objects

[ncheater]

I'm fairly new to MR but the batch bake to texture seems to be pretty straight forward when I read the help.
My test scene has 5 objects (4 poly cubes scaled & rotated to form a floor and walls and a poly sphere in the middle). All awfully colored with different lambert materials without any fancy shaders to keep it as simple as possible.

It renders ok with MR so the lighting is working.

But when I use bake to texture (fully lit) one of my objects turns out completly black?? the others have the shadows and color correctly baked in the textures.

Any clues anyone? I'm using Maya 6.5

[joojaa]

Chak the objects normals are pointing outward! Also chek the shader it is assigned!

[ncheater]

Thanks for the fast reply but..
The normals are pointing outwards on all objects.
And one object that is working, is a duplicate of one that doesnt work (just rotated) so ist not the shader : (

I managed to get all to work if I rotated the non working objekt so that the side is pointing "up" use bake . hitting undo, rotate back to correct position, the use bake again.
Which makes me even even more confused...

[mandrak]

Is it duplicated, or instanced? Check that out - it shouldn't work with instances.
Also, there might be a sharing problem with shaders, so You could try recreating new shading network for the object in question.

[ncheater]

Hmm Nope
The object is duplicated as copy.
And applying a new material didnt help either : (

this it what is look like, how can rotating it make any difference ???

[failure]

Disable shadow casting for walls

[ncheater]

Made some difference, but not usefull.
Turned off Casts Shadows under Render Stats for the 2 walls. correct ?

Instead of a totally black object I got a stripe along the left side with a tint of red, and the rest black as before.

If anyone would like to try and reproduce the error here is the file just run batch bake and see if it look the same, or if it's just my computer (or me) thats stupid

[failure]

ma please

[mandrak]

I think one row of Your UV's is conected into one streched face that is spread all over entire map, so You get this artifact. FOr baking to be successful, UV's can't overlap.

[ncheater]

Thankz a ton
Here as ma

[mandrak]

Nope, sorry. I've checked it out now, so I see they are ok.
I think it has to have sth with the way mr calculates fg inh baking. There's some difference in max/min values in these two.

[joojaa]

the min max radius settings MUST be set manualy whan baking as mr has no clue on how big the objects are compared to cam views (yes its explained in the manual under beking with mr).

But no that does not seem to be the point here.

[failure]

No, uv's are not ok. They must be in 0-1 range.

[ncheater]

Je I saw that but since the other objects worked with baking I didnt set the max min, somehow it does figure out how big it is ( or it just works...)

And why the H... does rotating the object in a sertain way solve the problem ??

[failure]

It doesn't. it just happens to look like it in this particular case. ( Well almost because you still have artefacts on third picture - note the squeezed ball shadow on both sides of the blue box )

If you have overlapping uv's or uv's out of 0-1 range ( which is technically same as overlapping ) the renderer will have to store two or more pixels in the same place in texture. Which is of course not possible so the one that is rendered/stored last is the one you see as the end result. This tends to look like a pretty random behavior if you don't understand what's underneath.

Min and max fg radius has nothing to do with this.

[ncheater]

Jeee
Thankz everyone
Newer checked the uv's didnt think they could mess up when just using simple cubes.
I got the same reply now from Alias support that the UV's are outside the 0-1 range.
But U all were 2 days behind with the question and gave me reply's and the solution faster : )