How can I increment/decrement a multidemensional array without a loop?

[Hendrix]

Hi, I would like to pick four elements from a multidemensional array
and use the content of those elements. I want to do this without all
the subscript calls required for individual access, just want this for
speed. I know you can increment regular arrays via ++array or array++
etc. etc. but how do you do it with multidemensional arrays? lets say
I have array[x][y] and I need to access array[x+1][y+1] how can I do
this without the subscripts? The x and y count is at 64 by the way.

Thanks for any help.

 

[Ivan Vecerina]

Hi, I would like to pick four elements from a multidemensional array
and use the content of those elements. I want to do this without all
the subscript calls required for individual access, just want this for
speed. I know you can increment regular arrays via ++array or array++
etc. etc. but how do you do it with multidemensional arrays? lets say
I have array[x][y] and I need to access array[x+1][y+1] how can I do
this without the subscripts? The x and y count is at 64 by the way.

It's as simple as:
itemPtr += (rowLen+1);
Or in the case you mention:
itemPtr += 65;
Assuming that itemPtr points within: Item dataArray[64][64]; and
is in-range.

Note that, when starting to fiddle with item address calculations
in multi-dimensional arrays, I would recommend using a 1-dimensional
array and doing all offset calculations manually. While IIRC the
sub-arrays are supposed to be contiguous, using a consistent
approach should be preferred IMO.

hth,