Simple array init question

[Daniel Keep]

Graham wrote:
> A floating point texture buffer - 3 floats per pixel, and (say) 640x480
> pixels.
> 
> Manfred Nowak wrote:
>> Graham wrote
>>
>>> several thousand elements large.
>>
>> In what domains do one need to represent dense multidimensional
>> structures with O(1) time for accesses of elements?
>>
>> -manfred 

Perhaps you shouldn't be using jagged arrays, then.  int[][] is *NOT* a
multidimensional array.  It's basically equivalent to this:

struct int_array
{
    int* ptr;
    size_t length;
}

struct int_array_array
{
    int_array* ptr;
    size_t length;
}

int_array_array buffer;

Notice those nested pointers; that means that your texture is not
necessarily contiguous in memory, which would make, for example, loading
the texture into GL a pain in the behind.  Not sure if the cache would
have problems...

I think there's a few multidimensional array templates floating
around... or if not, you can always write your own :)

	-- Daniel

-- 
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{
    return 4; // chosen by fair dice roll.
              // guaranteed to be random.
}

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