From 51181bd30be17b7b41540fda9eb56b71512c8ebd Mon Sep 17 00:00:00 2001
From: Jakub Melka <Mgr.Jakub.Melka@gmail.com>
Date: Thu, 27 Jul 2023 12:46:44 +0200
Subject: [PATCH] Issue #71: Pages are "mirrored"

---
 Pdf4QtLib/sources/pdfannotation.cpp          |  8 ++++----
 Pdf4QtLib/sources/pdfdrawspacecontroller.cpp |  7 ++++++-
 Pdf4QtLib/sources/pdfrenderer.cpp            | 12 ++++++++----
 3 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/Pdf4QtLib/sources/pdfannotation.cpp b/Pdf4QtLib/sources/pdfannotation.cpp
index 6dd96ca..b41f4cf 100644
--- a/Pdf4QtLib/sources/pdfannotation.cpp
+++ b/Pdf4QtLib/sources/pdfannotation.cpp
@@ -1205,10 +1205,10 @@ PDFAnnotationManager::~PDFAnnotationManager()
 }
 
 QTransform PDFAnnotationManager::prepareTransformations(const QTransform& pagePointToDevicePointMatrix,
-                                                     QPaintDevice* device,
-                                                     const PDFAnnotation::Flags annotationFlags,
-                                                     const PDFPage* page,
-                                                     QRectF& annotationRectangle) const
+                                                        QPaintDevice* device,
+                                                        const PDFAnnotation::Flags annotationFlags,
+                                                        const PDFPage* page,
+                                                        QRectF& annotationRectangle) const
 {
     // "Unrotate" user coordinate space, if NoRotate flag is set
     QTransform userSpaceToDeviceSpace = pagePointToDevicePointMatrix;
diff --git a/Pdf4QtLib/sources/pdfdrawspacecontroller.cpp b/Pdf4QtLib/sources/pdfdrawspacecontroller.cpp
index d2dce86..a565a3e 100644
--- a/Pdf4QtLib/sources/pdfdrawspacecontroller.cpp
+++ b/Pdf4QtLib/sources/pdfdrawspacecontroller.cpp
@@ -709,10 +709,15 @@ QTransform PDFDrawWidgetProxy::createPagePointToDevicePointMatrix(const PDFPage*
 
         case PageRotation::Rotate180:
         {
-            matrix.translate(0, rectangle.top() + rectangle.bottom());
+            matrix.translate(rectangle.left(), rectangle.top() + rectangle.bottom());
             matrix.scale(1.0, -1.0);
+            matrix.translate(rectangle.width(), 0);
+            matrix.scale(-1.0, 1.0);
+            matrix.translate(-rectangle.left(), 0);
             Q_ASSERT(qFuzzyCompare(matrix.map(rectangle.topLeft()).y(), rectangle.bottom()));
             Q_ASSERT(qFuzzyCompare(matrix.map(rectangle.bottomLeft()).y(), rectangle.top()));
+            Q_ASSERT(qFuzzyCompare(matrix.map(rectangle.topLeft()).x(), rectangle.right()));
+            Q_ASSERT(qFuzzyCompare(matrix.map(rectangle.bottomRight()).x(), rectangle.left()));
             break;
         }
 
diff --git a/Pdf4QtLib/sources/pdfrenderer.cpp b/Pdf4QtLib/sources/pdfrenderer.cpp
index ecef9ad..cf64e44 100644
--- a/Pdf4QtLib/sources/pdfrenderer.cpp
+++ b/Pdf4QtLib/sources/pdfrenderer.cpp
@@ -52,8 +52,8 @@ PDFRenderer::PDFRenderer(const PDFDocument* document,
 }
 
 QTransform PDFRenderer::createPagePointToDevicePointMatrix(const PDFPage* page,
-                                                        const QRectF& rectangle,
-                                                        PageRotation extraRotation)
+                                                           const QRectF& rectangle,
+                                                           PageRotation extraRotation)
 {
     PageRotation pageRotation = getPageRotationCombined(page->getPageRotation(), extraRotation);
     QRectF mediaBox = page->getRotatedBox(page->getMediaBox(), pageRotation);
@@ -72,6 +72,7 @@ QTransform PDFRenderer::createMediaBoxToDevicePointMatrix(const QRectF& mediaBox
         {
             matrix.translate(rectangle.left(), rectangle.bottom());
             matrix.scale(rectangle.width() / mediaBox.width(), -rectangle.height() / mediaBox.height());
+            matrix.translate(-mediaBox.left(), -mediaBox.top());
             break;
         }
 
@@ -80,6 +81,7 @@ QTransform PDFRenderer::createMediaBoxToDevicePointMatrix(const QRectF& mediaBox
             matrix.translate(rectangle.left(), rectangle.top());
             matrix.rotate(90);
             matrix.scale(rectangle.width() / mediaBox.width(), -rectangle.height() / mediaBox.height());
+            matrix.translate(-mediaBox.left(), -mediaBox.top());
             break;
         }
 
@@ -89,6 +91,7 @@ QTransform PDFRenderer::createMediaBoxToDevicePointMatrix(const QRectF& mediaBox
             matrix.rotate(-90);
             matrix.translate(-rectangle.height(), 0);
             matrix.scale(rectangle.width() / mediaBox.width(), -rectangle.height() / mediaBox.height());
+            matrix.translate(-mediaBox.left(), -mediaBox.top());
             break;
         }
 
@@ -96,6 +99,9 @@ QTransform PDFRenderer::createMediaBoxToDevicePointMatrix(const QRectF& mediaBox
         {
             matrix.translate(rectangle.left(), rectangle.top());
             matrix.scale(rectangle.width() / mediaBox.width(), rectangle.height() / mediaBox.height());
+            matrix.translate(mediaBox.width(), 0);
+            matrix.translate(-mediaBox.left(), -mediaBox.top());
+            matrix.scale(-1.0, 1.0);
             break;
         }
 
@@ -106,8 +112,6 @@ QTransform PDFRenderer::createMediaBoxToDevicePointMatrix(const QRectF& mediaBox
         }
     }
 
-    matrix.translate(-mediaBox.left(), -mediaBox.top());
-
     return matrix;
 }