From b8f5a7ea02f1e9ba56fa41102b16c1fc3bea6dff Mon Sep 17 00:00:00 2001
From: Konstantin Baierer <unixprog@gmail.com>
Date: Tue, 25 Aug 2020 15:39:55 +0200
Subject: [PATCH] use polygon_for_parent from ocrd_utils

---
 ocrd_tesserocr/crop.py           |  2 +-
 ocrd_tesserocr/segment_region.py | 28 +---------------------------
 2 files changed, 2 insertions(+), 28 deletions(-)

diff --git a/ocrd_tesserocr/crop.py b/ocrd_tesserocr/crop.py
index 77d5493..e28eb98 100644
--- a/ocrd_tesserocr/crop.py
+++ b/ocrd_tesserocr/crop.py
@@ -9,6 +9,7 @@
     coordinates_of_segment,
     bbox_from_polygon,
     bbox_from_points,
+    polygon_for_parent,
     polygon_from_bbox,
     points_from_polygon,
     bbox_from_xywh,
@@ -27,7 +28,6 @@
 from ocrd import Processor
 
 from .config import TESSDATA_PREFIX, OCRD_TOOL
-from .segment_region import polygon_for_parent
 
 TOOL = 'ocrd-tesserocr-crop'
 LOG = getLogger('processor.TesserocrCrop')
diff --git a/ocrd_tesserocr/segment_region.py b/ocrd_tesserocr/segment_region.py
index df5e1ec..4867fd2 100644
--- a/ocrd_tesserocr/segment_region.py
+++ b/ocrd_tesserocr/segment_region.py
@@ -1,7 +1,6 @@
 from __future__ import absolute_import
 
 import os.path
-from shapely.geometry import Polygon
 from tesserocr import (
     PyTessBaseAPI,
     PSM, RIL, PT
@@ -12,6 +11,7 @@
     make_file_id,
     assert_file_grp_cardinality,
     coordinates_for_segment,
+    polygon_for_parent,
     polygon_from_points,
     polygon_from_x0y0x1y1,
     points_from_polygon,
@@ -23,7 +23,6 @@
     MetadataItemType,
     LabelsType, LabelType,
     CoordsType,
-    PageType,
     OrderedGroupType,
     ReadingOrderType,
     RegionRefIndexedType,
@@ -304,28 +303,3 @@ def _process_page(self, it, page, page_image, page_coords, page_id):
             not og.get_UnorderedGroupIndexed()):
             # schema forbids empty OrderedGroup
             ro.set_OrderedGroup(None)
-
-def polygon_for_parent(polygon, parent):
-    """Clip polygon to parent polygon range.
-    
-    (Should be moved to ocrd_utils.coordinates_for_segment.)
-    """
-    childp = Polygon(polygon)
-    if isinstance(parent, PageType):
-        if parent.get_Border():
-            parentp = Polygon(polygon_from_points(parent.get_Border().get_Coords().points))
-        else:
-            parentp = Polygon([[0,0], [0,parent.get_imageHeight()],
-                               [parent.get_imageWidth(),parent.get_imageHeight()],
-                               [parent.get_imageWidth(),0]])
-    else:
-        parentp = Polygon(polygon_from_points(parent.get_Coords().points))
-    if childp.within(parentp):
-        return polygon
-    interp = childp.intersection(parentp)
-    if interp.is_empty:
-        # FIXME: we need a better strategy against this
-        raise Exception("intersection of would-be segment with parent is empty")
-    if interp.type == 'MultiPolygon':
-        interp = interp.convex_hull
-    return interp.exterior.coords[:-1] # keep open