Introducing Starling

MovieClip

We saw previously how to use the Sprite API in Starling, but what about animations like with MovieClip? Every Flash developer is familiar with the concept of movieclip, for the past few years, most AS3 developers have recreated the MovieClip API based on BitmapData to accelerate rendering through the use of bitmaps, but also to get independent framerate for each MovieClip.

Figure 1-33 illustrates a sprite atlas showing each frame of our MovieClip.

Figure 1-33. A sprite atlas for our running boy

The idea is that each frame will be sampled by the GPU and displayed in our scene; by updating the texture on each frame we will reproduce the concept of movieclip. So how do we create this animation? Well, Flash Pro is your best friend for that, each frame of your animation is exported to a sequence of images. Then those images are loaded into a tool like TexturePacker (http://www.texturepacker.com), which exports them merged into a single texture used to feed our MovieClip object. Note that Flash Pro CS6 is able to generate Starling sprite atlases directly from a MovieClip, so you can benefit from a tighter integration.

Figure 1-34 illustrates the frames of a sprite atlas:

Figure 1-34. Frames in a sprite atlas

If you are mipmapping your sprite atlas, you need to make sure you that there ...