Let's have a look at how scripts can be used to control the progress of a game. Loops repeat when a statement is true.
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this script simply loops from the given conditiontest = 10 decrementing by 1 each time, test -= 1 down to 0 displaying the value of test and then exits the level. |
As long as a given condition is true, the while loop will repeat 0 or more times. A while loop evaluates its test expression before executing the body of the loop. |
Okay, so counting down for a ten count and then exiting the level may not be much of a gameplay, however, the principle is valid for many scenarios. A popular application of a while loop is to check if a certain type of monster has been completely wiped out and then something happens, like a door opens or closes, or a sector rises or lowers.
For example:
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A do loop is simply a while loop turned on its head. First comes the loop, then the test expression. |
Unlike a while loop, a do loop always executes at least once. |
Again an example to do the same as before, count from 10 to 0 and end the level.
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In a for loop the initialzing test and modifying expressions are grouped
in one area, separated by a semicolon. |