diff options
| -rw-r--r-- | converter/ppm/ppmtospu.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/converter/ppm/ppmtospu.c b/converter/ppm/ppmtospu.c index c655ca05..5bbbc2d3 100644 --- a/converter/ppm/ppmtospu.c +++ b/converter/ppm/ppmtospu.c @@ -245,9 +245,10 @@ sort(struct PixelType * const pixelType, int i, j; /* Rearrange so that everything less than 'pivot' is on the left side of - the subject array slice, while everything else is on the right side (we - won't know until we're done where the dividing line between the sides - is), then sort those two sides. + the subject array slice and everything greater than is on the right + side and elements equal could be on either side (we won't know until + we're done where the dividing line between the sides is), then sort + those two sides. */ assert(left <= right); @@ -259,8 +260,10 @@ sort(struct PixelType * const pixelType, --j; if (i <= j) { - /* A pixel not less popular than pivot is to the left of a pixel - less popular than pivot, so swap them. + /* An element not less popular than pivot is to the left of a + pixel not more popular than pivot, so swap them. Note that we + could be swapping equal (pivot-valued) elements. Though the + swap isn't necessary, moving 'i' and 'j' is. */ swapPixelType(pixelType, i, j); ++i; |