So, what we have covered so far makes the work flow run something like this:
- Get the idea and make a picture of it: draw, photo, whatever. See the ‘Images’ section above on how to do that.
- Build the high poly model. Use modifiers and all the Blender tools available to easy the building.
- Once you have the model, decide if you want to bake a texture using the Blender lighting. Texture baking is a whole other tutorial.
- If you want to bake a texture, you need to make the UVMap and handle the texture creation at this point. Save the file and use a copy for making the new topology for levels of detail. Come back to the copy without the UVMap to continue modeling for the LoD’s.
- If you are not going to bake textures, you can skip the UVMap for now. I’m proceeding as if you chose not to bake a texture.
- Once the dress or blouse is modeled and texture baked or not, You need to make the lower poly model that will be the ‘high poly’ model for Second Life’s HIGH LoD. I place that model on its own layer. I usually use layers 6 to 9 for my LoD models.
- Make a mesh that is as low a poly model as will provide the shape and flexibility you need. The key is in making Edge Loops that will work with the deformation of the joints. Elbows and knees need to bend correctly. You can see the rings in image #### (Rings.jpg)
- Notice that the rings provide compression and expansion places for the arm to bend (A). The shoulder to arm joint does the same. However, the shoulder has complete rings (B) and incomplete rings (C). In general, avoid incomplete rings when possible. But, don’t go crazy avoiding them. The incomplete rings work but they can confuse some Blender tools. When the Edge Ring and Slide (Ctrl-R) works you are doing a good job on your rings.
- Once you have the HIGH LoD model built you are ready to consider your next step.
- If you are making clothes you are ready to start rigging and weight painting the HIGH LoD to test how it moves. This is an area of modeling that requires experience. You can gain some experience watching weight painting tutorials. But, you will only start to learn how this works when you start doing it. I am going to put that part in a separate tutorial. So, this tutorial splits for clothes makers and object makers.
- If you are making a table, chair, car, house, or other object that will not need to be animated, you are ready to start on the MEDIUM LoD and work your way to the LOWEST.
- With the LoD’s made you can start making materials and textures for the HIGH LoD and work your way to the LOWEST LoD. Again texturing and UVMapping are tutorials of their own. I won’t go into them here.
- I will advise you that each mesh item can have 8 materials/textures.
- All LoD models should contain the same number of materials/textures. This requirement comes and goes. It is safer to include them than have to come back and add them. You can hide textures on single triangles in the lower LoD’s if necessary.
- Create a shape for your physics layer. This is the shape the Havok Physics Engine will use to calculate collisions. It is the shape an avatar would walk on. The simpler this shape is the lower your Land Impact and upload cost will be.
- For most things a cube (12 polys) is a good physics shape. It is possible to use a single plane (4 vertices – 2 polys). Some have worked it down to a a single triangle. If avatars can bump into your object from different directions a cube is a safe bet. But, experiment.
- With clothing the physics layer is superfluous. The avatar’s collision hull is used. Keep your physics layer as simple as possible.
- The physics layer does not need a material/texture. From time to time an error has slipped in and the uploader insisted on the Physics Layer having the same number of materials as your HIGH LoD. But, that is a bug.
- Once the LoD’s and textures are ready, you can export for Second Life. I’ll include more details in another tutorial. But, I have a bit of the information in Page 8 of the Clothing Setup Tutorial.
With these tools in mind look through Gaia Clary’s YouTube tutorials.
Mesh attachments (Dress) – Modeling a simple dress. 6:43 minutes
Mesh Rigging – Rigging mesh dress. 4:50 minutes
Mesh Weighting – Shows weight painting. 9:02 minutes
These three videos cover the basic concepts. They do rely on Avastar, a program marketed by Gaia Clary and Domino Marama. It makes many tasks much simpler. I think it is worth the money in time saved. But, for learning Blender and understanding modeling, rigging, and weight painting you can’t beat doing it yourself.
This hopefully gives you the hard-to-find tools you need to work with models for Second Life. I know it lacks detail on the actual modeling. But, I was concerned that until you are rigging clothes much of what I would put in here wouldn’t make sense. Also, there are hundreds of video tutorials on character and model creation. I did not want to duplicate that information.
My next tutorial will be on weight painting. I’ll build a tight fitting skirt, rig it, and weight it. It will include setting up the rigging and showing the problems with weight painting for the Second Life avatar. I’ll be doing more with Bsurface too.
One of the challenges is ‘texture stretch.’ It is possible to minimize some stretch problems, but we can’t eliminate them. Even with the mystical Avatar 2.0 we would have stretch problems.
Q & A
If you are having a problem finding information on how to do something, ask in the comments. The keywords here are ‘problem finding.’ Most of the things we need to do are in a number of various tutorials.