Game Development Reference
Figure 13-8 . Tracing the shape of a flipper with an alpha threshold to ignore the image shadow
Tip If for any reason the Shape Tracer result isn't what you want, and neither
the Tolerance nor the Alpha threshold setting lets you fix the shape, you can
still manually edit the shape after closing the Shape Tracer. Just click any vertex
and drag it. You can also double-click a vertex to remove it or double-click a
line segment between two vertices to add a new vertex.
Repeat the same process for the flipper-right image. And don't forget to set the
collision bits for both flippers. You'll want to check the Flipper category and the
Mask check box in the Ball row. Figure 13-8 shows the correct collision bit settings.
You should set the anchor point of the left flipper to Pixel coordinates 27,78—and
97,79 for the right flipper.