Flash MX 2004 Games : Art to ActionScript

}
}
return false;
Chapter 8: In tip-top condition
This little function returns true if the point (x, y) is inside the rectangle (left, top, right, bottom).
To use the function in the first example we would use:
if (pointInRect(clip._x, clip._y, 100, 200, 300, 400)){
//Do something
}
‘Examples/Chapter08/Conditions02.fla’ shows this function in action.
But if we want to run the code if the character is inside the rectangle (100, 200, 300, 400) or
the rectangle (400, 25, 500, 127) then we can combine two calls to the function using:
if (pointInRect(clip._x, clip._y, 100, 200, 300, 400) ||
pointInRect(clip._x, clip._y, 400, 25, 500, 127)){
//Do something
}
The symbol ‘||’ is the logical Or, if one side or the other of the symbol is true then the combined
result is true. Notice how Flash allows you to put a long line onto two or more lines; Flash ignores
what is referred to as ‘white space’ which includes spaces and carriage returns, so you can fit the
code into a narrower text box.
Let’s try out a more colourful example
When you are learning about using any sort of
programming language there is no substitute for
hands-on experience. We are going to look at a
practical example of the ‘if ’ statement in action and
you are firmly encouraged to run your copy of Flash
and open ‘Examples\Chapter08\Conditions03.fla’.
Take a look at the _root level timeline. There are
five layers; each layer has been named with a relevant
name. Most of the code we are going to study
is in the layer ‘Control’ on frame 1. When declaring
new functions for a movie clip or _root level
timeline, frame 1 is a good place to put the new
function code. In this example we will be using a
function that is placed on the first frame.
The purpose of the program is to detect when
Figure 8.2 The layers used in the
Conditions03 project
the mouse arrow overlaps with the box in the middle of screen. As well as detecting the overlap,
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