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>> SPEAKER 1: Let's take a look at a
program that I've been working on that

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has two sprites, each of which
has its own script.

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The biggest takeaway of this program is
that you can indeed have not only

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two sprites, but those sprite
scripts can run in parallel.

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That is, at the same time, which is to
say that's from scratch gives us

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multithreaded programming environment,
whereby two things can happen

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literally at the same time.

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>> Now here we have first
our bird sprite.

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And notice that this bird
has one script.

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Let's zoom in.

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Now according to this script, when the
green flag is clicked the bird is

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going to move to negative 150, 150.

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So really, the top left-hand
corner of the stage.

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And then he's going to point downward
at a 45-degree angle.

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>> Then he's forever going
to do the following.

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If he is not touching the cat,
he's going to move three

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steps or three pixels.

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And if he's on the edge of the
stage, he's going to bounce.

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And then he is going to do that
again and again and again.

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In other words, this bird is going
to flutter around the stage.

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>> Meanwhile, the cat is going
to be doing the following.

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He's going to start at negative
160, negative 160.

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So really, the bottom left-hand
corner of the screen.

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And he's going to pick a random
direction in which to point.

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>> Thereafter, he's going to forever
do the following.

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If he's touching the bird, he's going
to play the lion sound and roar, and

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then he's going to stop, thereby
ending this animation.

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Otherwise he's going to point himself
toward the bird and move one step.

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>> In other words, the cat is going to
perpetually follow this bird, but not

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quite at the same pace, thereby giving
the bird a bit of an advantage.

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Well, let's see what happens when
we do run these scripts.

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>> Let's go ahead and click
our green flag.

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And they're off.

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Notice that the bird is coming
up on the edge of the stage.

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And, indeed, he bounces.

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And again, bounces off that edge.

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>> The cat, meanwhile, is really
homing in on this bird.

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He's almost about to catch him after
one more bounce it seems.

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And--

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>> [ROAR]

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SPEAKER 1: Indeed, he's been caught.

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