Re: 90 Rotation in one buffer only


Hi,

> //image width and height
> int w, h;

> //only first quadrant
> int w2 = w / 2;
> int h2 = h / 2;

> //loop through pixels
> for(int j = 0; j < h2; j++) {
> for(int i = 0; i < w2; i++) {
> tmp = getPixel(i, j);
> setPixel(i, j, getPixel(i, h - j));
> setPixel(i, h - j, getPixel(w - i, h - j));
> setPixel(w - i, h - j, getPixel(w - i, j));
> setPixel(w - i, j, tmp);
> }
> }

Except that this doesn't work. If you split your image into four parts,
labeled 1,2,3,4 from left to right, top to bottom, this flips 3 to 1, 4 to
3, 2 to 4 and 1 to 2. However, each of these operations is a mirroring.
If 1,2,3,4 contain letters, they will come out "left handed" after this
operation has been performed. Thus, no rotataion here, sorry.

So long,
Thomas
.

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