From 4f312b8de423ee06c5c39bbe79d7da80cb27a0db Mon Sep 17 00:00:00 2001
From: Roy Qu <royqh1979@gmail.com>
Date: Fri, 29 Mar 2024 00:54:33 +0800
Subject: [PATCH] fix: left/top pos after font size changed

---
 libs/qsynedit/qsynedit/document.cpp |  1 -
 libs/qsynedit/qsynedit/qsynedit.cpp | 20 ++++++++++++--------
 libs/qsynedit/qsynedit/qsynedit.h   |  3 ++-
 3 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/libs/qsynedit/qsynedit/document.cpp b/libs/qsynedit/qsynedit/document.cpp
index e1409a79..c5f89ce5 100644
--- a/libs/qsynedit/qsynedit/document.cpp
+++ b/libs/qsynedit/qsynedit/document.cpp
@@ -1013,7 +1013,6 @@ QList<int> Document::calcGlyphPositionList(const QString &lineText, const QList<
         right += gWidth;
     }
     return glyphPostionList;
-
 }
 
 int Document::xposToGlyphIndex(int line, int xpos)
diff --git a/libs/qsynedit/qsynedit/qsynedit.cpp b/libs/qsynedit/qsynedit/qsynedit.cpp
index 2d5d1a56..e6b808c0 100644
--- a/libs/qsynedit/qsynedit/qsynedit.cpp
+++ b/libs/qsynedit/qsynedit/qsynedit.cpp
@@ -155,9 +155,9 @@ QSynEdit::QSynEdit(QWidget *parent) : QAbstractScrollArea(parent),
     hideCaret();
 
     connect(horizontalScrollBar(),&QScrollBar::valueChanged,
-            this, &QSynEdit::onScrolled);
+            this, &QSynEdit::onHScrolled);
     connect(verticalScrollBar(),&QScrollBar::valueChanged,
-            this, &QSynEdit::onScrolled);
+            this, &QSynEdit::onVScrolled);
     connect(verticalScrollBar(), &QAbstractSlider::sliderReleased,
             this, &QSynEdit::ensureLineAlignedWithTop);
     //enable input method
@@ -286,6 +286,8 @@ bool QSynEdit::canRedo() const
 int QSynEdit::maxScrollWidth() const
 {
     int maxWidth = mDocument->maxLineWidth();
+    if (maxWidth <= 0)
+        return INT_MAX; //all inlines invalid. Next paintEvent() will update it.
     if (useCodeFolding())
         maxWidth += stringWidth(syntaxer()->foldString(""),maxWidth);
     if (mOptions.testFlag(eoScrollPastEol))
@@ -3074,7 +3076,6 @@ void QSynEdit::doOnStatusChange(StatusChanges)
 
 void QSynEdit::updateHScrollbar()
 {
-    int nMaxScroll;
     int nMin,nMax,nPage,nPos;
     if (mPaintLock!=0) {
         mStateFlags.setFlag(StateFlag::sfHScrollbarChanged);
@@ -3087,9 +3088,8 @@ void QSynEdit::updateHScrollbar()
                 setHorizontalScrollBarPolicy(Qt::ScrollBarPolicy::ScrollBarAlwaysOn);
             }
             if (mScrollBars == ScrollStyle::ssBoth ||  mScrollBars == ScrollStyle::ssHorizontal) {
-                nMaxScroll = maxScrollWidth();
                 nMin = 0;
-                nMax = nMaxScroll;
+                nMax = maxScrollWidth();
                 nPage = viewWidth();
                 nPos = mLeftPos;
                 horizontalScrollBar()->setMinimum(nMin);
@@ -3735,15 +3735,19 @@ void QSynEdit::onChanged()
     emit changed();
 }
 
-void QSynEdit::onScrolled(int)
+void QSynEdit::onHScrolled(int)
 {
-    incPaintLock();
     mLeftPos = horizontalScrollBar()->value();
+    invalidate();
+}
+
+void QSynEdit::onVScrolled(int)
+{
     mTopPos = verticalScrollBar()->value();
     invalidate();
-    decPaintLock();
 }
 
+
 const PFormatter &QSynEdit::formatter() const
 {
     return mFormatter;
diff --git a/libs/qsynedit/qsynedit/qsynedit.h b/libs/qsynedit/qsynedit/qsynedit.h
index c228901a..d5f59ea8 100644
--- a/libs/qsynedit/qsynedit/qsynedit.h
+++ b/libs/qsynedit/qsynedit/qsynedit.h
@@ -664,7 +664,8 @@ private slots:
     void onUndoAdded();
     void onSizeOrFontChanged();
     void onChanged();
-    void onScrolled(int value);
+    void onHScrolled(int value);
+    void onVScrolled(int value);
 
 private:
     std::shared_ptr<QImage> mContentImage;