Page 127 - Learn To Program With Scratch

Stage’s backpack
Sprite’s backpack
costume #, costume STAGE
x-position, y-position, name, volume #,
direction, costume #, graphic effects, etc.
costume name, size,
volume, graphic
effects, etc. Variables with scope
For all sprites
All variables with
scope For this
sprite only clone
clone

Clone1 backpack Clone2 backpack
x-position, y-position, x-position, y-position,
direction, costume #, direction, costume #,
costume name, size, costume name, size,
volume, graphic volume, graphic
effects, etc. effects, etc.
All variables with All variables with
scope For this scope For this
sprite only sprite only

Figure 5-15: Clones inherit copies of their parent’s variables

To illustrate, let’s say the parent sprite owns a variable named speed
whose current value is 10. When you clone the parent, the new sprite will
also have a variable named speed with the value 10. After that, if the parent
sprite changes speed to 20, the value of speed in the clone will stay at 10.
CloneIDs .sb2 You can use this concept to distinguish between clones in your applica-
tions. For example, let’s look at the program in Figure 5-16.

The parent sprite and
its three clones, each
with its own unique ID

Figure 5-16: Using variables to distinguish between clones

Variables 105

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