From 82709ea38309bfbdffd70be1695e6617351adc9c Mon Sep 17 00:00:00 2001
From: Mathieu Pellerin <nirvn.asia@gmail.com>
Date: Sun, 18 Oct 2026 17:39:53 +0700
Subject: [PATCH] Add a QGIS patch to speed up project loading with large
 project files

---
 vcpkg/ports/qgis/portfile.cmake               |  1 +
 .../qgis/project_load_optimization.patch      | 62 +++++++++++++++++++
 2 files changed, 63 insertions(+)
 create mode 100644 vcpkg/ports/qgis/project_load_optimization.patch

diff --git a/vcpkg/ports/qgis/portfile.cmake b/vcpkg/ports/qgis/portfile.cmake
index 05f3e5dd32e..dd1bc2f26f9 100644
--- a/vcpkg/ports/qgis/portfile.cmake
+++ b/vcpkg/ports/qgis/portfile.cmake
@@ -15,6 +15,7 @@ vcpkg_from_github(
         processing.patch # Needed to avoid link issue with tinygltf (ATM embedded into QGIS) and _GEOSQueryCallback defined multiple times
         mesh.patch
         vector_tiles_dpi_fix.patch
+        project_load_optimization.patch
 )
 
 
diff --git a/vcpkg/ports/qgis/project_load_optimization.patch b/vcpkg/ports/qgis/project_load_optimization.patch
new file mode 100644
index 00000000000..75b80183429
--- /dev/null
+++ b/vcpkg/ports/qgis/project_load_optimization.patch
@@ -0,0 +1,62 @@
+diff --git a/src/core/project/qgsproject.cpp b/src/core/project/qgsproject.cpp
+index c2220801b7f..8df9e7157a8 100644
+--- a/src/core/project/qgsproject.cpp
++++ b/src/core/project/qgsproject.cpp
+@@ -2141,32 +2141,37 @@ bool QgsProject::readProjectFile( const QString &filename, Qgis::ProjectReadFlag
+     return false;
+   }
+ 
+-  QTextStream textStream( &projectFile );
+-  QString projectString = textStream.readAll();
+-  projectFile.close();
+-
+-  for ( int i = 0; i < 32; i++ )
++  if ( !doc->setContent( &projectFile ) )
+   {
+-    if ( i == 9 || i == 10 || i == 13 )
++    projectFile.seek( 0 );
++    QTextStream textStream( &projectFile );
++    QString projectString = textStream.readAll();
++    projectFile.close();
++
++    for ( int i = 0; i < 32; i++ )
+     {
+-      continue;
++      if ( i == 9 || i == 10 || i == 13 )
++      {
++        continue;
++      }
++      projectString.replace( QChar( i ), u"%1%2%1"_s.arg( FONTMARKER_CHR_FIX, QString::number( i ) ) );
+     }
+-    projectString.replace( QChar( i ), u"%1%2%1"_s.arg( FONTMARKER_CHR_FIX, QString::number( i ) ) );
+-  }
+ 
+-  // location of problem associated with errorMsg
+-  int line, column;
+-  QString errorMsg;
+-  if ( !doc->setContent( projectString, &errorMsg, &line, &column ) )
+-  {
+-    const QString errorString = tr( "Project file read error in file %1: %2 at line %3 column %4" ).arg( projectFile.fileName(), errorMsg ).arg( line ).arg( column );
+-    QgsDebugError( errorString );
+-    setError( errorString );
++    int line, column;
++    QString errorMsg;
++    if ( !doc->setContent( projectString, &errorMsg, &line, &column ) )
++    {
++      const QString errorString = tr( "Project file read error in file %1: %2 at line %3 column %4" ).arg( projectFile.fileName(), errorMsg ).arg( line ).arg( column );
++      QgsDebugError( errorString );
++      setError( errorString );
+ 
+-    return false;
++      return false;
++    }
++  }
++  else
++  {
++    projectFile.close();
+   }
+-
+-  projectFile.close();
+ 
+   QgsDebugMsgLevel( "Opened document " + projectFile.fileName(), 2 );
+