Mesh/Exporting a mesh from 3ds Max

Mesh

• Basics

• Advanced

• Project Information

• Technical Information

• Mesh creation tools
  • Sample mesh content
  • 3DS Max
  • Blender
  • Maya
  • Sketchup
  • ZBrush
  • Other tools

Software Setup

Recent versions of 3ds Max have the Autodesk Collada Exporter included in the software. For older versions or as an alternative, you can get the OpenCollada plugin from the OpenCOLLADA Download Page or OpenCollada project page.

• Note: Even using the latest version of 3ds Max (2011 at time to write this), you need update your Autodesk Collada Exporter if you want export your meshes properly without problems. The Autodesk Collada Exporter is included (and free to download) in the FBX Plug-ins. You can download the latest version from Autodesk FBX page. OpenCOLLADA can't export meshes for SL. The exported file lost the UV coordinates and can't be rigged, so use Autodesk Collada instead.

Basic workflow

Scale to meters

One meter in 3D Studio Max converts to one meter in Second Life. In order for your model to upload with the expected scale, you will need to change Max's units to metric since it isn't the default unit settings.

To Set Up the Correct Scale for Your 3D Studio Max Scene:

1. From the top drop down menu, select "Customize" --> "Units Setup..."

2. In the "Units Setup" dialog box that appears, select "Metric" in the "Display Unit Scale" field. (At Default, Max has the units set to "Generic Units")

3. Under Metric you can choose between millimeters, centimeters, meters, and kilometers via a drop down menu.

Which metric system you would like to use depends on what you're creating. So long as you’re working in metric units, any metric system you choose to work in will upload equally in Second Life. Choosing meters should ideally work for most mesh creations for Second Life. If you are working on very small meshes like jewelery, choosing centimeters may prove more helpful.

4. Click on the button "System Unit Setup" in the "Units Setup" dialog box

5. In the "System Unit Setup" dialog box that appears, you'll probably see the following: "1 Unit = 1.0 Inches" as this is the default setting. Select the drop down menu for "Inches" and select a metric unit instead. For example: If you're using meters for the Display Unit Scale, select Centimeters to replace Inches here.

Reduce polygons

Keeping Track of Your Triangle Count

3D Studio Max has a utility that can keep a count of how many triangles or polygons you have in a selected object. This will be useful during the process of either cutting down or bulking up your model’s topology for your High, Medium, Low, and Lowest LODs meshes.

Adding the Utility “Polygon Counter” to Max’s (vers.2010) Default List of Utilities:

1. Go to the Command Panel and click on the “Utilities” (The Hammer) Tab.
2. Click on “Config Button Sets” Button - it is the button to the right of the “Sets” Button
3. In the “Config Button Sets” dialog box, there is a drop down menu for “Total Buttons”. 3D Studio Max 2010’s default list is set to 9 buttons. Bump the number up to ten. When you scroll down the right “Utilities” column, there will be a new blank button added to this list.
4. Find the utility named “Polygon Counter” under Max Standard in the left “Utilities” column. Click and drag “Polygon Counter” to the new blank button you just added. Click OK or Save the list as a new utility set and this will add the Polygon Counter Utility to the commonly used list of utilities in the Utilities Tab.

The Polygon Counter utility counts either triangles or polygons in a selected object(s) and it also gives a tally for all geometry in the scene. For the purposes of creating for Second Life, you will want to keep the count type set as “Count Triangles”. The Budget fields are values you can set yourself. It represents the maximum number of triangles/polygons you’ve allotted yourself for a model or a scene of models. Setting a Triangle/Polygon Budget will not affect your model if you go over budget.

UV texture Mapping

Part 1 http://www.youtube.com/watch?v=vUUhOCEujUI Part 2 http://www.youtube.com/watch?v=AApNZtlhei8 Part 3 http://www.youtube.com/watch?v=9DjqFpS6Nw8

Export to COLLADA

Before you export your mesh, make sure that it doesn’t have any stray vertices, overlapping edges, or ngons (polygons that have more than four vertices). These will either cause unexpected visual results in Second Life or worse, the mesh will fail to upload entirely.

Once that’s done, select the mesh and...

1. Go to File --> Export --> Export Selected

2. Select the directory you wish to save the exported .dae file and create a name for it.

3. In the “Save as type:” drop down menu, select “Autodesk Collada (.DAE)”. Note: If you are using an older version of Max that does not have this file type available, you will need to download the OpenCollada Plugin and select “OpenCOLLADA (.DAE)” from the menu list.

4. Autodesk Collada export will open a FBX Export dialog box. You shouldn’t need to change much to the default settings. If you’re exporting a skinned mesh, make sure “Animation” and “Deformations” are checked off. For all meshes, make sure that the “Up Axis” is set to “Z-up”. If the axis isn’t set to Z-up, the mesh axis(and the rig data) will be flipped on its side and/or rotated in Second Life. This will wreak havoc on a skinned mesh.

Best practices

[NOTE: All these links need to be updated because of the Forum software changing, and the threads being archived]

Forum thread on 3ds Max best practices

Forum request for input on debugging 3ds Max import workflow

Another forum thread on exporting a rigged mesh from 3ds Max

Forum thread on UVW mapping, mostly about 3ds Max

Forum thread on texturing in Max and uploading to Second Life