--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/tesseract/src/textord/blkocc.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,248 @@
+/******************************************************************************
+ *
+ * File:         blkocc.h  (Formerly blockocc.h)
+ * Description:  Block Occupancy routines
+ * Author:       Chris Newton
+ *
+ * (c) Copyright 1991, Hewlett-Packard Company.
+ ** Licensed under the Apache License, Version 2.0 (the "License");
+ ** you may not use this file except in compliance with the License.
+ ** You may obtain a copy of the License at
+ ** http://www.apache.org/licenses/LICENSE-2.0
+ ** Unless required by applicable law or agreed to in writing, software
+ ** distributed under the License is distributed on an "AS IS" BASIS,
+ ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ ** See the License for the specific language governing permissions and
+ ** limitations under the License.
+ *
+ ******************************************************************************/
+
+#ifndef BLKOCC_H
+#define BLKOCC_H
+
+#include "elst.h"
+#include "params.h"
+
+namespace tesseract {
+
+class C_BLOB;
+
+/***************************************************************************
+CLASS REGION_OCC
+
+  The class REGION_OCC defines a section of outline which exists entirely
+  within a single region. The only data held is the min and max x limits of
+  the outline within the region.
+
+  REGION_OCCs are held on lists, one list for each region.  The lists are
+  built in sorted order of min x. Overlapping REGION_OCCs are not permitted on
+  a single list. An overlapping region to be added causes the existing region
+  to be extended. This extension may result in the following REGION_OCC on the
+  list overlapping the amended one. In this case the amended REGION_OCC is
+  further extended to include the range of the following one, so that the
+  following one can be deleted.
+
+****************************************************************************/
+
+class REGION_OCC : public ELIST_LINK {
+public:
+  float min_x;         // Lowest x in region
+  float max_x;         // Highest x in region
+  int16_t region_type; // Type of crossing
+
+  REGION_OCC() = default; // constructor used
+  // only in COPIER etc
+  REGION_OCC( // constructor
+      float min, float max, int16_t region) {
+    min_x = min;
+    max_x = max;
+    region_type = region;
+  }
+};
+
+ELISTIZEH(REGION_OCC)
+#define RANGE_IN_BAND(band_max, band_min, range_max, range_min) \
+  (((range_min) >= (band_min)) && ((range_max) < (band_max)))
+/************************************************************************
+Adapted from the following procedure so that it can be used in the bands
+class in an include file...
+
+bool    range_in_band[
+              range within band?
+int16_t band_max,
+int16_t band_min,
+int16_t range_max,
+int16_t range_min]
+{
+  if ((range_min >= band_min) && (range_max < band_max))
+    return true;
+  else
+    return false;
+}
+***********************************************************************/
+#define RANGE_OVERLAPS_BAND(band_max, band_min, range_max, range_min) \
+  (((range_max) >= (band_min)) && ((range_min) < (band_max)))
+/************************************************************************
+Adapted from the following procedure so that it can be used in the bands
+class in an include file...
+
+bool    range_overlaps_band[
+              range crosses band?
+int16_t band_max,
+int16_t band_min,
+int16_t range_max,
+int16_t range_min]
+{
+  if ((range_max >= band_min) && (range_min < band_max))
+    return true;
+  else
+    return false;
+}
+***********************************************************************/
+/**********************************************************************
+  Bands
+  -----
+
+  BAND 4
+--------------------------------
+  BAND 3
+--------------------------------
+
+  BAND 2
+
+--------------------------------
+
+  BAND 1
+
+Band 0 is the dot band
+
+Each band has an error margin above and below. An outline is not considered to
+have significantly changed bands until it has moved out of the error margin.
+*************************************************************************/
+class BAND {
+public:
+  int16_t max_max; // upper max
+  int16_t max;     // nominal max
+  int16_t min_max; // lower max
+  int16_t max_min; // upper min
+  int16_t min;     // nominal min
+  int16_t min_min; // lower min
+
+  BAND() = default; // constructor
+
+  void set(                  // initialise a band
+      int16_t new_max_max,   // upper max
+      int16_t new_max,       // new nominal max
+      int16_t new_min_max,   // new lower max
+      int16_t new_max_min,   // new upper min
+      int16_t new_min,       // new nominal min
+      int16_t new_min_min) { // new lower min
+    max_max = new_max_max;
+    max = new_max;
+    min_max = new_min_max;
+    max_min = new_max_min;
+    min = new_min;
+    min_min = new_min_min;
+  }
+
+  bool in_minimal( // in minimal limits?
+      float y) {   // y value
+    return (y >= max_min) && (y < min_max);
+  }
+
+  bool in_nominal( // in nominal limits?
+      float y) {   // y value
+    return (y >= min) && (y < max);
+  }
+
+  bool in_maximal( // in maximal limits?
+      float y) {   // y value
+    return (y >= min_min) && (y < max_max);
+  }
+
+  // overlaps min limits?
+  bool range_overlaps_minimal(float y1,   // one range limit
+                              float y2) { // other range limit
+    if (y1 > y2) {
+      return RANGE_OVERLAPS_BAND(min_max, max_min, y1, y2);
+    } else {
+      return RANGE_OVERLAPS_BAND(min_max, max_min, y2, y1);
+    }
+  }
+
+  // overlaps nom limits?
+  bool range_overlaps_nominal(float y1,   // one range limit
+                              float y2) { // other range limit
+    if (y1 > y2) {
+      return RANGE_OVERLAPS_BAND(max, min, y1, y2);
+    } else {
+      return RANGE_OVERLAPS_BAND(max, min, y2, y1);
+    }
+  }
+
+  // overlaps max limits?
+  bool range_overlaps_maximal(float y1,   // one range limit
+                              float y2) { // other range limit
+    if (y1 > y2) {
+      return RANGE_OVERLAPS_BAND(max_max, min_min, y1, y2);
+    } else {
+      return RANGE_OVERLAPS_BAND(max_max, min_min, y2, y1);
+    }
+  }
+
+  bool range_in_minimal( // within min limits?
+      float y1,          // one range limit
+      float y2) {        // other range limit
+    if (y1 > y2) {
+      return RANGE_IN_BAND(min_max, max_min, y1, y2);
+    } else {
+      return RANGE_IN_BAND(min_max, max_min, y2, y1);
+    }
+  }
+
+  bool range_in_nominal( // within nom limits?
+      float y1,          // one range limit
+      float y2) {        // other range limit
+    if (y1 > y2) {
+      return RANGE_IN_BAND(max, min, y1, y2);
+    } else {
+      return RANGE_IN_BAND(max, min, y2, y1);
+    }
+  }
+
+  bool range_in_maximal( // within max limits?
+      float y1,          // one range limit
+      float y2) {        // other range limit
+    if (y1 > y2) {
+      return RANGE_IN_BAND(max_max, min_min, y1, y2);
+    } else {
+      return RANGE_IN_BAND(max_max, min_min, y2, y1);
+    }
+  }
+};
+
+/* Standard positions */
+
+#define MAX_NUM_BANDS 5
+#define UNDEFINED_BAND 99
+#define NO_LOWER_LIMIT -9999
+#define NO_UPPER_LIMIT 9999
+
+#define DOT_BAND 0
+
+/* Special occupancy code emitted for the 0 region at the end of a word */
+
+#define END_OF_WERD_CODE 255
+
+extern double_VAR_H(textord_underline_threshold);
+
+bool test_underline(  // look for underlines
+    bool testing_on,  // drawing blob
+    C_BLOB *blob,     // blob to test
+    int16_t baseline, // coords of baseline
+    int16_t xheight   // height of line
+);
+
+} // namespace tesseract
+
+#endif