Creating a clothes library: some technical aspects

[ThomasL]

It turned out that the simple rig had no weights for the helpers - the rig file was made before the helpers were introduced. Now fixed in svn. Also improved weighting of skirt between legs in game and 2life rigs.

[Maia1003]

What happens if you import the character with the Helper Geometry option selected? The original clothes were made before the helpers were introduced, so they follow the body, whereas I think duststorm's clothes follow the helpers.

Good point. Though I don't think it's the cause. Linking to an armature in blender is done by assigning vertex groups to bones right?
Anyway, it's important to know whether it works in blender or not.
I still think it's an issue with the OSG exporter. Some limitation it can't get past.

Hi all,

Thank you for responding.
Everything works fine when rendering with Blender.

My concern is why these basic clothes behave accordingly with the body and not duststrom's clothes ?
I am not sure it is only related to OSG...

duststorm, have you created other clothes so that I can try them again ?

It is true that OSG would prefer to have a single mesh with a single texture layer and a single rig: I already post a question about how to use those clothes created with Makeclothes and join them to one mesh with the body. Someone replies that it would be a nightmare ! Could you suggest how to do that ?

Another point is that when I export a nude model in .obj in 3DS max, the model is well exported and I even don't need to delete the eyebrows and eyelashes meshes.
I need to try with dressed clothes, and as far as I understand, the clothes will be exported as separate meshes and again araises the issue of joining/merging the clothes ...

Maybe, a better approach would be definetely to get a one mesh (clothes and body), and again how would I do that from Makehuman and MakeClothes ?

Thank you very much.

Maia

[Maia1003]

It turned out that the simple rig had no weights for the helpers - the rig file was made before the helpers were introduced. Now fixed in svn. Also improved weighting of skirt between legs in game and 2life rigs.

Thanks ThomasL.
Duststorm, may I ask you to re-make your clothes with this improved version ?
Being able to put the clothes directly on the body is so interesting. Real-time cloth simulation could be experienced with OSG this way.

Thank you,
Maia

[ThomasL]

Duststorm, may I ask you to re-make your clothes with this improved version ?

No need for to change anything. The clothes follow the helper geometry, as they always have. The only thing that has changed is that the helpers are now moving with the bones.

But this bug only affected the simple rig. If your character was exported with another rig, e.g. the default mhx rig, nothing has changed, and the problem must still be there.

[Maia1003]

Try to stick at least below 10.000 polygons (that is tris, a quad consists of two tris. Since MH meshes only use quads you need to multiply the count by two to know the polycount in the engine)
.

Could you explain more here ? Why these number (10 000 polygons) ? It seems you know a lot about the matter, could you suggest reading about real-time rendering perfomance issues ?

Basic examples exist for the exporter and they are working for these simple examples.
I will check about the bone count, that seems important.

Thank you a lot,

Maia

[Maia1003]

Duststorm, may I ask you to re-make your clothes with this improved version ?

No need for to change anything. The clothes follow the helper geometry, as they always have. The only thing that has changed is that the helpers are now moving with the bones.

But this bug only affected the simple rig. If your character was exported with another rig, e.g. the default mhx rig, nothing has changed, and the problem must still be there.

So, with what rig should I export to Blender ?

Maia

[Maia1003]

What happens if you import the character with the Helper Geometry option selected? The original clothes were made before the helpers were introduced, so they follow the body, whereas I think duststorm's clothes follow the helpers.

helpers.png

Edit: Hm. But that cannot affect the shoes, since there are no helpers around the feet. Nevertheless, this is the only major difference compared to the original clothes is that I can think of.

As a newbie and knowing nothing about the underlying MH algorithms, so my question seems naive: isn't it logical that the clothes follow the body (as for th original clothes) instead of the helpers ?

[ThomasL]

For lingerie, yes. The helpers were introduced to cover the case that real clothes do not follow the body shape very closely. The most extreme case is a skirt between the legs, which is very far from any body part, especially in a pose where the legs are apart. Also an overcoat hides the body form pretty well, so needs helper geometry (which does not yet exist) do adapt to all targets.

[Maia1003]

For lingerie, yes. The helpers were introduced to cover the case that real clothes do not follow the body shape very closely. The most extreme case is a skirt between the legs, which is very far from any body part, especially in a pose where the legs are apart. Also an overcoat hides the body form pretty well, so needs helper geometry (which does not yet exist) do adapt to all targets.

Hi,

I understand that MH is designed to work closely with Blender but there are some issues for those who would like to use it outside Blender.
E.g, I tried to import the model to Blender with Helper geometry as you suggest: the helpers disappear when rendering with Blender, but when exporting to another format (osg), they are exported and must be deleted manually with the diamonds. The clothes don't follow either.

I understand that MH team could not take into account every single request, but for such a case, it is frustrating that the clothes do not follow the body because of the helpers. Is it possible to have some kind of checker box to enable/disable that ?

[duststorm]

Someone replies that it would be a nightmare !

I wouldn't be offput too much by someone's personal opinion which is not backed with proper explanation or experience. It's actually very logical that you would attempt such a thing if you were serious about getting MH characters into a realtime engine.

Look at my reply in the respective topic, I have posted some general directions and a tutorial video.

As for polycount and such, since I have quite a bit experience with realtime rendering engines, I have picked up a few good guidelines here and there. Deciding on polygon count, texture resolution, amount of different materials, ... really is a decision you should make taking into account the intended audience and the power of the machines that will be running it.

A good way of determining the detail you want to aim for is to look at video games. Look for a game which performance requirements you want to equal and find out what restrictions it uses. For example recent games have polycounts of 5000 to even 10000 for important characters. If you don't want to force your public into buying recent hardware, you might want to lower this number, and compare to somewhat older games for example.
A very important aspect for graphics performance these days is the tradeoff between number of polygons and amount of batches. A batch is a set of polygons that is rendered for one object with the same material. So a MH character with 5 different materials would result in 5 batches. The number of batches that are visible on one screen in one frame translate linearly in the time needed for the graphics card to process the image. (they are processed one by one in screen space)
Since modern graphics cards are fairly fast in processing lots of triangles, the optimal tactic is to group a good amount of polygons within one batch. Wasting a batch with only few geometry is not good for performance, but having too large batches might not be good either (since you will lose the advantages of culling unneeded geometry out of the picture, are limited on texture size, etc)
I don't have any good reading links handy, but I might have dropped some useful links in this thread if I remember correctly.
There are however a lot of indications on batchcount/polycount usage to be found on the net, along with comparisons from other games.

Again, how you should create your content depends for a large part on the specifics of the engine you are using. Have a look around for specific information for OSG.