Merge pull request #121 from KOLANICH/2BoxVector

Added a vector between 2 boxes which may be useful for users of the library

pdfminer/utils.py

@@ -292,6 +292,28 @@ def matrix2str(m):
     (a, b, c, d, e, f) = m
     return '[%.2f,%.2f,%.2f,%.2f, (%.2f,%.2f)]' % (a, b, c, d, e, f)
 
+def vecBetweenBoxes(obj1, obj2):
+    """A distance function between two TextBoxes.
+
+    Consider the bounding rectangle for obj1 and obj2.
+    Return vector between 2 boxes boundaries if they don't overlap, otherwise returns vector betweeen boxes centers
+             +------+..........+ (x1, y1)
+             | obj1 |          :
+             +------+www+------+
+             :          | obj2 |
+    (x0, y0) +..........+------+
+    """
+    (x0, y0) = (min(obj1.x0, obj2.x0), min(obj1.y0, obj2.y0))
+    (x1, y1) = (max(obj1.x1, obj2.x1), max(obj1.y1, obj2.y1))
+    (ow, oh) = (x1-x0, y1-y0)
+    (iw, ih) = (ow-obj1.width-obj2.width, oh-obj1.height-obj2.height)
+    if iw<0 and ih<0:
+        # if one is inside another we compute euclidean distance
+        (xc1, yc1) = ( (obj1.x0+obj1.x1)/2, (obj1.y0+obj1.y1)/2 )
+        (xc2, yc2) = ( (obj2.x0+obj2.x1)/2, (obj2.y0+obj2.y1)/2 )
+        return (xc1-xc2, yc1-yc2)
+    else:
+        return (max(0, iw), max(0, ih))
 
 ##  Plane
 ##