From a6cef65c0713b7bb55315a0d4f1cfd83f90bf3c1 Mon Sep 17 00:00:00 2001
From: McLoo <unknown>
Date: Fri, 21 Feb 2020 02:15:24 +0100
Subject: Backport: Feature [feature-requests:497] Automatically scroll while
 dragging text. Added automatic scrolling when text dragged near edge of
 window.

Backport of changeset 7989:e98f6731bd39.
---
 doc/ScintillaHistory.html |  5 +++++
 src/Editor.cxx            | 14 ++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/doc/ScintillaHistory.html b/doc/ScintillaHistory.html
index bdef04b8f..36b002bf5 100644
--- a/doc/ScintillaHistory.html
+++ b/doc/ScintillaHistory.html
@@ -544,6 +544,7 @@
 	<td>Andreas Falkenhahn</td>
 	<td>Mark Reay</td>
 	<td>David Shuman</td>
+	<td>McLoo</td>
     </tr>
     </table>
     <p>
@@ -588,6 +589,10 @@
 	CF_UNICODETEXT.
 	</li>
 	<li>
+	Automatically scroll while dragging text.
+	<a href="https://sourceforge.net/p/scintilla/feature-requests/497/">Feature #497</a>.
+	</li>
+	<li>
 	On Win32, the numeric keypad with Alt pressed can be used to enter characters by number.
 	This can produce unexpected results in non-numlock mode when function keys are assigned.
 	Potentially problematic keys like Alt+KeypadUp are now ignored.
diff --git a/src/Editor.cxx b/src/Editor.cxx
index 5da9f2b75..1256082ed 100644
--- a/src/Editor.cxx
+++ b/src/Editor.cxx
@@ -4257,6 +4257,20 @@ void Editor::SetDragPosition(SelectionPosition newPos) {
 		posDrop = newPos;
 	}
 	if (!(posDrag == newPos)) {
+		const int oldCaretYPolicy = caretYPolicy;
+		const int oldCaretYSlop = caretYSlop;
+		const int oldCaretXPolicy = caretXPolicy;
+		const int oldCaretXSlop = caretXSlop;
+		caretYPolicy = CARET_SLOP | CARET_STRICT | CARET_EVEN;
+		caretYSlop = 2;
+		caretXPolicy = CARET_SLOP | CARET_STRICT | CARET_EVEN;
+		caretXSlop = 50;
+		MovedCaret(newPos, posDrag, true);
+		caretYPolicy = oldCaretYPolicy;
+		caretYSlop = oldCaretYSlop;
+		caretXPolicy = oldCaretXPolicy;
+		caretXSlop = oldCaretXSlop;
+
 		caret.on = true;
 		FineTickerCancel(tickCaret);
 		if ((caret.active) && (caret.period > 0) && (newPos.Position() < 0))
-- 
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