--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/tesseract/src/textord/equationdetectbase.cpp	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,68 @@
+///////////////////////////////////////////////////////////////////////
+// File:        equationdetectbase.cpp
+// Description: The base class equation detection class.
+// Author:      Zongyi (Joe) Liu (joeliu@google.com)
+// Created:     Fri Aug 31 11:13:01 PST 2011
+//
+// (C) Copyright 2011, Google Inc.
+// 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.
+//
+///////////////////////////////////////////////////////////////////////
+
+#ifdef HAVE_CONFIG_H
+#  include "config_auto.h"
+#endif
+
+#include "equationdetectbase.h"
+
+#include "blobbox.h"
+
+#include <allheaders.h>
+
+namespace tesseract {
+
+// Destructor.
+// It is defined here, so the compiler can create a single vtable
+// instead of weak vtables in every compilation unit.
+EquationDetectBase::~EquationDetectBase() = default;
+
+void EquationDetectBase::RenderSpecialText(Image pix, BLOBNBOX *blob) {
+  ASSERT_HOST(pix != nullptr && pixGetDepth(pix) == 32 && blob != nullptr);
+  const TBOX &tbox = blob->bounding_box();
+  int height = pixGetHeight(pix);
+  const int box_width = 5;
+
+  // Coordinate translation: tesseract use left bottom as the original, while
+  // leptonica uses left top as the original.
+  Box *box = boxCreate(tbox.left(), height - tbox.top(), tbox.width(), tbox.height());
+  switch (blob->special_text_type()) {
+    case BSTT_MATH: // Red box.
+      pixRenderBoxArb(pix, box, box_width, 255, 0, 0);
+      break;
+    case BSTT_DIGIT: // cyan box.
+      pixRenderBoxArb(pix, box, box_width, 0, 255, 255);
+      break;
+    case BSTT_ITALIC: // Green box.
+      pixRenderBoxArb(pix, box, box_width, 0, 255, 0);
+      break;
+    case BSTT_UNCLEAR: // blue box.
+      pixRenderBoxArb(pix, box, box_width, 0, 255, 0);
+      break;
+    case BSTT_NONE:
+    default:
+      // yellow box.
+      pixRenderBoxArb(pix, box, box_width, 255, 255, 0);
+      break;
+  }
+  boxDestroy(&box);
+}
+
+} // namespace tesseract