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I got a 2D array of values that represent a b&w(1 or 0) bitmap(64x64).. Now i need to read the bitmap in a spiral way starting from (31,31) and store them in a 1 dimensional array.. I've been trying to come up with an efficient algorithm for some time now.... Can somebody please help me out?
thx
Perhaps present your algorithm first, then there's no danger of suggesting what you've already tried.
Well when I try stepping along a square shaped spiral, I move 1 pixel up, 1 pixel right, 2 pixels down, 2 pixels left, 3 pixels up, 3 pixels right, 4 pixels down etc..
So it seems that your move lengths are 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6 etc.
I.e movelength(n) = (n+1)/2
Or you simply increment the move length after each time you move horizontally.
Last of all you have to track your direction e.g.
0 = up
1 = right
2 = down
3 = left
Keep cycling through those.