bugfix [#24331] EdgeSlide not as flawless as 2.49's

ensure minimum mouse distance for sliding edge verts else it becomes unusable.

1 files changed, 20 insertions, 1 deletions

diff --git a/source/blender/editors/transform/transform.c b/source/blender/editors/transform/transform.c
index e6a42b9a921..a43078e5d6a 100644
--- a/source/blender/editors/transform/transform.c
+++ b/source/blender/editors/transform/transform.c
@@ -4563,7 +4563,26 @@ static int createSlideVerts(TransInfo *t)
 	start[0] = t->mval[0];
 	start[1] = t->mval[1];
 	add_v3_v3v3(end, start, vec);
-	
+
+
+	/* Ensure minimum screen distance, when looking top down on edge loops */
+#define EDGE_SLIDE_MIN 30
+	if (len_squared_v2v2(start, end) < (EDGE_SLIDE_MIN * EDGE_SLIDE_MIN)) {
+		if(ABS(start[0]-end[0]) + ABS(start[1]-end[1]) < 4.0f) {
+			/* even more exceptional case, points are ontop of eachother */
+			end[0]= start[0];
+			end[1]= start[1] + EDGE_SLIDE_MIN;
+		}
+		else {
+			sub_v2_v2(end, start);
+			normalize_v2(end);
+			mul_v2_fl(end, EDGE_SLIDE_MIN);
+			add_v2_v2(end, start);
+		}
+	}
+#undef EDGE_SLIDE_MIN
+
+
 	sld->start[0] = (short) start[0];
 	sld->start[1] = (short) start[1];
 	sld->end[0] = (short) end[0];