[gthumb] curve editor: consider only the x coordinate to select the point

[Paolo Bacchilega <paobac src gnome org>]

commit fe652c3d86eb77aad9d851d0f5c8810bcc35bb1e
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Wed Jan 7 12:33:51 2015 +0100

    curve editor: consider only the x coordinate to select the point

 extensions/file_tools/gth-curve-editor.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/extensions/file_tools/gth-curve-editor.c b/extensions/file_tools/gth-curve-editor.c
index 5fffe24..a8a7d06 100644
--- a/extensions/file_tools/gth-curve-editor.c
+++ b/extensions/file_tools/gth-curve-editor.c
@@ -580,7 +580,8 @@ gth_curve_editor_get_nearest_point (GthCurveEditor  *self,
                GthPoint *q = &points->p[i];
                double    d;
 
-               d = sqrt (SQR (q->x - p->x) + SQR (q->y - p->y));
+               d = q->x - p->x;
+               d = ABS (d);
                if ((d < POINT_ATTRACTION_THRESHOLD) && ((*n == -1) || (d < min))) {
                        min = d;
                        *n = i;