by Julie Applegate:
Creating 3D objects for iBooks
You may have used Strata tools in the past to add 3D to PDF documents and web pages. This gives you a way to add 3D to iPad, iPhone and iPod Touch documents. So now you can show off your 3D skills everywhere!
You can use Strata Design 3D CX 7, Design 3D CXi or Design 3D SE to export 3D objects for use with Apple’s iBooks Author. You will need Design 3D CX 7.0.3 or higher, Design 3D CXi v7.03 or higher, or Design 3D SE v6.2.4 or higher.
To use 3D content from the other Strata 3D products you’ll want to import the object into one of these Strata Design 3D products.
In Design 3D CX, CXi or SE, use the Export command to export a Collada (.dae) file. iBooks Author will import Collada files as 3D objects.
When targeting Collada and/or iBooks Author, it’s a good idea to make a copy of your model, and then modify the copy to create a version that better fits the iBooks/Collada purpose.
-Any textures you use that are greater than 1024 x 1024 pixels will be resized to 1024 x 1024 (by iBooks Author).
-Some files will produce multiple texture map .jpgs on export to Collada. These are textures which have been applied individually to parts of your object; groups, shapes or multiple objects.
-If the texture does produce multiple .jpg files, you will need to keep them in the same folder as the Collada file. The Collada file references these .jpgs and if they are moved, your object’s textures may not appear in iBooks.
You can use a camera in Design 3D to set up your view in iBooks. Here’s a quick way to do it:
-Insert your object(s), and set up your scene.
-Use the View tools to adjust the scene to the view you want.
-Select “New Camera From View” in the Modeling window’s Plus menu to create a new camera.
-Deselect everything – if you select only the camera, when you Export only the camera will be exported and the scene will appear empty.
-If you export with only object(s) selected, the camera’s view will not be exported with the file. In this situation your object’s orientation in iBooks may not be what you expect.
-You can export multiple objects to iBooks, as long as you don’t exceed the recommended polygon count (see Polygon Count section below).
-When exporting from Design if there are selected objects then only those supported objects that are selected will be exported. If there is no selection then all supported objects will be exported.
-If your objects appear inside out or if you can see through your object in iBooks, you may need to convert the object to a polygon mesh before exporting.
-If you can still see through your object in iBooks, you may have some backfacing polygons (reversed normals) in your object.
-To see the issues in Design 3D, select the object, then check “One Sided” in the Object tab of the Object Properties palette. Now turn on Backface Culling in the preferences and set your Modeling window display to GL Smooth. This should allow you to easily see any backfacing polygons in your object.
-If your object is a polygon mesh, you can use the Show Face Normals command in poly edit mode to find reversed normals (backfacing polygons). This command is new in Design 3D CX version 7.5.
The first-generation iPad is optimized for viewing 3D objects with fewer than 20,000 moderately textured polygons. The second-generation iPad (iPad 2) supports viewing 3D objects in a completed book with up to 50,000 moderately textured polygons. More complicated objects may result in an increased load time, slower behavior, or a blurry image.
You can check an object’s polygon count in Design 3D CX, CXi or SE.
Go to the Info panel of the Details palette. Choose Model or View Stats, then click the Collect button. This will display the number of polygons in your model of view.
Collada Export Options
When exporting to Collada for iBooks Author, make sure the .jpg option is checked. You should leave the other options unchecked.
For a more in-depth, video tutorial check out Chris Tyler’s project of a 9 volt battery blister pack. Chris created two tutorials showing you how to texture and render a sophisticated product packaging project. In this third tutorial he shows you how to translate that render-ready project into an iBooks-ready project. See it here.
To get started with the first tutorial where Chris shows you how to UV map the battery go here.