Indigo 1.1.1

[Whaat]

I'm having trouble with the new subdivision features. If the the max number of subdivisions is set to zero, it renders fine. If the number of subdivisions is set to 1 or more, the geometry goes all crazy.

Am I missing something here? I have tried this with several different meshes and every time, the triangles 'blow up'.

I am not using displacement mapping or anything.

Code: Select all

 <normal_smoothing>false</normal_smoothing>
 <max_num_subdivisions>1</max_num_subdivisions>
<subdivide_pixel_threshold>0.0</subdivide_pixel_threshold>
<subdivide_curvature_threshold>0.0</subdivide_curvature_threshold>
<subdivision_smoothing>true</subdivision_smoothing>

[cpfresh]

same here actually. i cant even get a simple cube to subdivide without either 'blowing-up' (like a balloon) so large as it blocks the entire scene. either that or the cube faces actually blow apart (refer to attached images)

is there a way to find out exactly what the subdivision strings actually mean to the geometry of the model? itd help alot when trying to figure out what is going on.

[OnoSendai]

Hi guys,
as you've found out, the subdivision code (with smoothing) is pretty fussy when it comes to mesh topology.

For starters, the mesh needs to be a 2-manifold, and cannot currently have any boundaries. Subdivision smoothing on surfaces with boundaries will be supported in the next release.

Any pair of triangles are only considered adjacent by Indigo if they share an edge. An edge is shared if and only if the two triangles both index the two vertices making up the edge.

So what's probably tripping up a lot of people is that vertices shared between triangles must be written out to the scene file only once, and the triangles must index that vertex.

[fused]

ok. good to know. cindigo removes duplicate normals and texture coordinates from the exported objects (with the optimize option), but not vertices. will put that in, too.

[mrmoose]

I just try to use the Official Indigo Material Preview Scene and modified the previewmats.igs file to change the material. But if I add texture map an error popup...

How can i correct it?

Thanks

[drBouvierLeduc]

I had the same error. If I remember well, you must change the uv name of your material from "default" to "uv".

[mrmoose]

I had the same error. If I remember well, you must change the uv name of your material from "default" to "uv".

Thanks dr, it works!!!

[CTZn]

Hello ! At the beginning I thought that was stupid, but now I have to ask: is <subdivide_curvature_threshold> expressed in radians ?

Thanks !

[suvakas]

Hmm.. so it isn't as easy as I initially thought
I get the same kind of results than Whaat and I don't have a clue what to change. I'm using native Max routines for export so I can't alter how the vertices are stored inside obj or 3ds.

[Kosmokrator]

hhmmmm......

[CTZn]

Well suv I think we must learn to have more patience; we were warned that actual displacement stage was "fussy". I experienced this issue too, and i'm confident in that we will find improvements in the next releases.

Don't forget to use the <c> tag along with <b>, it will offset the surfaces in the direction of their normals if I'm correct.

We asked Ono for a test release and we get it: now test further

[OnoSendai]

Hi Suv, CTZn and other exporter writers,
come by the IRC channel,
#indigo on irc.enterthegame.com,
and we can discuss mesh topology issues.

[Whaat]

Hi guys,
as you've found out, the subdivision code (with smoothing) is pretty fussy when it comes to mesh topology.

Actually, the results were the same with or without subdivision smoothing enabled (ss long as max number of subdivisions is greater than 0)

So are you planning to make the subdivision code work with with this type of topology? (duplicate vertices) It definitely would make things easier for the exporter writers.

I always thought that duplicate vertices were unavoidable because the same vertex position can have multiple UV coordinates and vertex normals... How do you export the correct UVs if a vertex can only be listed once in the topology list?

[OnoSendai]

Hi Whaat,
If the surface is supposed to be C1 continuous, then the vertex normal depends only on the vertex position.
If the surface is not supposed to be C1 continuous, e.g. it's creased along an edge, then duplicate normals at the same position are alright, as each vertex can have a different normal.

UV coordinates may be a different issue. I guess the question is, will you ever need to have two different uv coordinates at the same vertex position, for different triangles, on a C1 continuous surface?

[PureSpider]

There is also another problem...
If the displacement, mesh subdivision and smoothing is off at all - just like with 1.0.9 - the mesh is sometimes not smoothed correctly in 1.1.1 but in 1.0.9 it is...