Texturing Meshes?

[SpookyHollows]

Hello! Hope I'm putting this in the right place. 
Anyways, I've been making some simple meshes in Blender, my first mesh came out okay, but I had to put a texture on it in SL. But now I made a chair model, it has a cushion on it too, so I want 2 different kinds of textures, one for the chair, and one for the cushion. How would I be able to do that in SL? I heard something about UV Mapping...? But how do I do that? How does UV Mapping work? Does it make the meshes textures show up correctly in SL? I'm a newb at these sort of things. 
I've watched many tutorials, but it's hard to keep track of it. x.x any help is greatly appreciated! 

 Small edit: I use Blender 2.73

[Reblend Weston]

Hi, i 've read ur post and i think i can share my knowledge. In Blender you must first use UV Unwrap method. How to do that there is allot of tutorials available in youtube. The second step is to corectly bake the texture ur applying to mesh. I do that by using cycles render, to enable also shadow effect on the objects. There is specific settings to do that in blender. Once the mesh is baked (with cycles render) u must than save the baked texture and the mesh model at the same time- only this will help to apply texture on mesh correctly). Do not forget to use blender settings when you export to collada the model. Upload texture and model seperately to SL and then use it. That way always works with me. If u need more help IM me inworld. Im giving you some example i recently did with Blender.

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[Rolig Loon]

There's no need to apply your textures in Blender.  In fact, there's a good argument for uploading your model without textures and then applying the textures in SL, as you have done already.  If you decide to offer your customers several texture options, it's a lot cheaper to upload the bare model once and then upload your  different textures at L$10 an upload than it is to upload several textured models.  If you decide to include a texture changer script so that your customers can change textures on the fly, you have to apply them on a bare model in world.

The vital step, regardless of where you apply the textures, is to do a decent job of creating a UV map while you're in Blender and then to define up to 8 areas (sets of polygons) on the model that will be the faces that you apply textures to later.  There are tons of tutorials about UV mapping.  Try the ones at machinimatrix.org for a start.  They're all designed for SL.  Like this series >>> http://machinimatrix.org/coffee-cup-tutorials/

[SpookyHollows]

But how do I apply multiple textures in SL? I only textured my first mesh in SL due to the fact I was having trouble with Blender, and the mesh only needed 1 texture.

I'd love to add scripts to my meshes in the future, but I have no knowledge of scripting. I have a simple UV map set up now too, do I need to bake it? I'm not sure how to do that with the textures in 2.73. 

[Rolig Loon]

As I said, once you have made your UV map, you can also define up to 8 sets of polygons ("faces" once your model is uploaded to SL) and you can apply a separate texture/color to each one if you want to, just as you can with any prim object that you texture in SL.  You don't need to bake anything in Blender if that's all you're doing.  You would only need to bake things if you were creating an Ambient Occlusion texture or applying some other textures in Blender itself.  I really do suggest watching at least one of the tutorial series at machinimatrix.com that I recommended earlier.

[SpookyHollows]

Sorry, I'm probably really annoying D:

I watched the tutorial you sent, but theres no other tutorials on there telling me how to do it. Like how to actually set up the faces. Even after I set up the UV map and uploaded the model to SL, it acts as 1 face, whenever I try to apply a texture it just goes over the whole model.

[Rolig Loon]

OK.... try this ...

That's a really simple model, with its UV map in the left window.  Notice that I have selected the Materials icon (top right) and have defined three materials ("Frame", "Glass" and "Material").  I did that in each case by clicking the "+" button to create a new material and giving it a name ("Glass" in the field that's highlighted here).  Then I have selected several polygons (one highlighted on the model at the moment) and clicked "Assign" to define those polygons as "Glass".  I assigned each of the polygons in my model to one of the three materials I have defined, and then saved everything.  When I upload the model to SL, face 0 in the uploaded model will be all of the areas that I have defined as "Frame".  Face 1 will be all the areas I have defined as "Glass" and face 2 will be all the areas I have defined as "Material".  SL lets you define up to 8 materials, so your uploaded model may have up to 8 faces.  You can apply the same texture to all of them if you want, or you can apply a different texture to each one, exactly the same way you would do it if you were applying textures to a prim cube.

[SpookyHollows]

OMG! Thank you so much! I'll have to make sure that I only use 8 materials when making a mesh. Hopefully SL can make it so you can have more faces in the future, but this makes it so much easier! 

[Rolig Loon]

Well, if you really must have more than 8 materials, you might consider dividing your model and uploading it in two parts.   Texture each separately and then link them.

[Drongle McMahon]

"Hopefully SL can make it so you can have more faces in the future"

In the development viewer Project-Import, this is possible, but it works by automatically splitting your mesh into multiple objects until each has no more than eight materials. It then gets imported as a linkset. Unfortunately, so far this has some rather unpleasant consequences. As usual for the automated uploader functions, you can do much better job by doing the splitting it yourself. So whether this will ever make it into the release viewer is unpredictable. My own view is that, since each material means another texture and so more loss of performance, it would be better to avoid it. We don't need chairs uploading a couple of dozen 1024x1024 textures before they can be rendered!