Game Development Reference
In-Depth Information
will still be used as references in the COLLADA document. This option is very useful when frequently exporting your
scene is necessary but you have not changed your images. It's also useful if you modify the images outside of Unity
and you do not want the exporter to delete your changes.
Lastly, the UV set option defaults to “Export First UV Set,” which is the texture mapping used for diffuse textures.
This version of this exporter only exports diffuse materials, so the other UV sets in the other choice in this menu,
“All Three UV Sets,” will be needed only if you know how to use the extra information in the application that will
import the COLLADA document.
Animation Options
For the animation export, the first choice here is whether or not to export any animations. If you select “Animation
export,” the exporter will automatically bake matrices in the scene and export animations as 4x4 matrices. The
animation clips options can be set to “Export All Clips” or “Export Single Clip.,” as shown in Figure
8-6
. If “Export
All Clips” is selected, all the animation curves will be stored at successive times, and the correct animation_clip
information with begin and end times for each clip will be exported. If the importer does not support the clip
information, the different animations will simply appear to be playing continuously one after another. See the single
key section for instructions on exporting just a single clip.
Figure 8-6.
Animated character from Angry Bots game
As for the evaluate frames option, the default is “Export All Animation Frames,” which will export one matrix
per frame of animation. If you select “Export Animation Keys,” only the matrices at keyframes will be exported.
This option should be used only if the software into which you want to import your COLLADA document is able to
interpolate the values between the keyframes.
The single key option defaults to “Eliminate Single Key Animation.” This is included because Unity allows single
key animation in clips that would freeze the animation to the value in that key.
