Some think BOM is a disaster and the majority of designers will not adopt it. I disagree.
You can ID some of the mental midgets in the forum that are having a problem figuring out what BOM will do and how it will be used. See Bakes on Mesh Feedback. Having debated some of these people on other issues I suspect they are arguing based on what they imagine BOM to be, not what it realIy is. They have done little if any research or experimenting to find reality.
Some think all clothing is reverting to system clothes. It isn’t. We will still have mesh clothes. Others think materials will be impossible to use with a mesh body taking advantage of BOM. This area is a bit more confusing, but I don’t see anything that will stop us using an Applier to add specular and normal maps to attachments as the BOM service doesn’t know about those layers.
So, the diffuse layer will come from BOM and specular and normal layers from an Applier.
How developers will implement materials for items using BOM and delivered using system-clothing items is up in the air. I suspect we will get a system-clothing item and an Applier for the material in the package we purchase.
I think we will see rapid mass adoption by content creators. BOM will remove, some say, 90% of their workload. So, adopting BOM will be a no-brainer.
UVMaps – Several people are thinking the old system clothes can be used on the new mesh bodies that are flagged to use BOM. Well, sort of yes. Why people would do that is WAY debatable. But, ‘why’ isn’t the current question, which are ‘can and how’.
In general, the current mesh bodies use UVMaps for tats, underwear, and clothes which are similar to the map for the classic avatar. But, there is no requirement for them to use the same map and some don’t.
The BOM doesn’t consider UVMaps. The one making the clothes handles that when they make the clothes. The designer targets the UVMap for which they are designing, which historically has been the classic avatar. The BOM is designed with that in mind and the assumption is it only needs to stack up textures made for similar UVMaps and composite them.
If a designer creates a mesh with a different UV map, say separate arms – left and right, that will work.
Cathy Foil gives a step by step in this post.
None of the new stuff breaks any of the old stuff. So, those using the classic avatar and classic clothes will only see a change in in texture quality going from 512 to 1024. If they make clothes they will see a few new options in the dialogs for new clothing but not anything they have to use.
None of this new stuff breaks any of the current mesh avatar bodies and attachments. Those using them will see no change.
Scripting this stuff is something we will learn more about later. Vir Linden on 4/9 said they aren’t there yet. (Ref) The scripting language doesn’t usually change until a project is well into RC. So, it is too soon to say what options we will have.
More… links below.