The "similarity" logic was giving added material way too much
negative weight. What we wanted to see was how similar the
post-change image was compared to the pre-change image, so the
natural definition of similarity is how much common things are
there, relative to the post-change image's size.
This simplifies things a lot.
Signed-off-by: Junio C Hamano <junkio@cox.net>
&src_copied, &literal_added))
return 0;
&src_copied, &literal_added))
return 0;
- /* Extent of damage */
- if (src->size + literal_added < src_copied)
- delta_size = 0;
- else
- delta_size = (src->size - src_copied) + literal_added;
-
- /*
- * Now we will give some score to it. 100% edit gets 0 points
- * and 0% edit gets MAX_SCORE points.
+ /* How similar are they?
+ * what percentage of material in dst are from source?
- score = MAX_SCORE - (MAX_SCORE * delta_size / base_size);
- if (score < 0) return 0;
- if (MAX_SCORE < score) return MAX_SCORE;
+ if (dst->size < src_copied)
+ score = MAX_SCORE;
+ else if (!dst->size)
+ score = 0; /* should not happen */
+ else
+ score = src_copied * MAX_SCORE / dst->size;