std::map

[ludoz]

typedef std::map<String, AnimationState> AnimationStateSet;

What's that ?? what return that ? how can i access animationState object from animationstateset ?

[:wumpus:]

http://www.sgi.com/tech/stl/Map.html

Nuff said, it is a dictionary that can look up AnimationState objects by name (String).

You can use the find method to look up a key in a Map, like

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AnimationStateSet::iterator found = set.find("SwimSwimHungry");
if(found != set.end())
{
    // The animation state has been found, do something with it
}

[haffax]

Welcome to the complex world of the STL. A very good STL reference can be found here.

A std::map is set of key-value pairs. So in the case of your map the key type is String and the value type is AnimationState. There are several ways to access elements in the container.

One way:

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AnimationState state = myAnimationStateSet["walkloop"];

This is the easiest way, but there are a few properties that you must be aware of. Look into the dokumentation for details.

Another way is through iterators:

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// set iterator to first element in map
AnimationStateSet::iterator it = myAnimationStateSet.begin();
// while loop for all elements in the map.
while(it != myAnimationStateSet.end())
{
    String key = it->first;
    String state = it->second;
    //do something with them
    .....
    ++it; // set iterator to the next element
}

You can't possibly learn STL in one day. You should look out for a tutorial or some such.

[:wumpus:]

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AnimationState state = myAnimationStateSet["walkloop"];

Don't do this! Use find(). It generates more code than find() as it creates "walkloop" in cases it did not exist yet (initializing it to default values), which is usually not what you want anyway. This is one of the traps that makes STL outright dangerous to people new to it. Only use the [] syntax to set values:

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myAnimationStateSet["walkloop"] = AnimationState(param, param2, ...);