If I understand correctly, are you asking how to actually find out what packet data is required for an action? If so, here goes....
Firstly, you need the sendPackets offset... Can find that on
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So, open up OllyDbg and set a breakpoint at this address. You will find it breaks here at random occasionally - The client sends packets requesting updates for things sometimes, so you have to be ready to hit run in Olly (F9) then very quickly perform the required action in game before you get another false trigger.
So, with that in mind, make sure Olly is running, then do something in game... For this example, I hit the meditate shortkey.
Olly should break, as per picture 1:
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Assuming all has gone well so far, if you now look in the stack window in Olly, the 2nd and 3rd values from the top are the ones you're interested, as outlined in the above pic.
The 2nd stack value (the top one in my red box) is the address of the packet data that is being sent (address 0x29B60A58). Note that this address changes every time a packet is sent.
Now, right click on this address in the stack and choose 'Follow in dump'.
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The memory window should now set it's origin at the address we want.
Now, note the 3rd value in the stack (the lower number in the red box on the first picture). This is the size of the packet, i.e., 2 bytes in this case.
So, looking at the memory window:
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We see the first two bytes are 0x2E, 0x00
If you take a look at the
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Note that some packets have parametric information too, such as playerId, or NPC / mob / resource IDs, etc. It's up to you to figure that stuff out ;)
Sorted =]
I have a feeling I may have misinterpreted the above question, but hopefully this is useful nonetheless :P