Need help with getting data from a DllCall. I'm bad at programming

[tqphan]

I'm making a DllCall to a function that requires a callback. The signature of the callback is as followed:

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typedef void (*tobii_gaze_point_callback_t)( tobii_gaze_point_t const* gaze_point, void* user_data );

So the two parameters for the callback are a pointer to a structure and another pointer to whatever that won't be used. I need the data from the first parameter. The structure is defined as follows:

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typedef struct tobii_gaze_point_t 
{
    int64_t timestamp_us;
    tobii_validity_t validity;
    float position_xy[ 2 ];
} tobii_gaze_point_t;

The first member of the structure is a "long long" which is an int64. The second member of the structure is an enum which is just an int (I think). The final member of the structure an array of 2 floats.



I register the callback with

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gaze_point_callback_address := RegisterCallback("gaze_point_callback", "Fast", 2)

.

I successfully call the dll and registered my callback and my callback function is being called. I'm having trouble extracting the data given to me.

My AHK callback fuction is as followed:

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gaze_point_callback(gaze_point, user_data)
{
    time_stamp := NumGet(gaze_point, 0, "Int64")
    validity := NumGet(gaze_point, 4, "Int")
    OutputDebug, %time_stamp%
}

I'm getting garbage numbers that doesn't make sense. Am I extracting data incorrectly? Also I am unsure how to extract the 2 floats. Please help !

[teadrinker]

If gaze_point is a pointer, should be

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gaze_point_callback(gaze_point, user_data)
{
    time_stamp := NumGet(gaze_point + 0, "Int64")
    validity := NumGet(gaze_point + 8, "Int")
    OutputDebug, %time_stamp%
}

[tqphan]

Thank you, sir! I'm getting the numbers that expected now.