Inverting colors feature

PdfForQtLib/sources/pdfdrawspacecontroller.cpp

@@ -600,6 +600,10 @@ void PDFDrawWidgetProxy::draw(QPainter* painter, QRect rect)
 
     // Use current paper color (it can be a bit different from white)
     QColor paperColor = getCMSManager()->getCurrentCMS()->getPaperColor();
+    if (m_features.testFlag(PDFRenderer::InvertColors))
+    {
+        paperColor = invertColor(paperColor);
+    }
 
     // Iterate trough pages and display them on the painter device
     for (const LayoutItem& item : m_layout.items)

PdfForQtLib/sources/pdfpainter.cpp

@@ -17,6 +17,7 @@
 
 #include "pdfpainter.h"
 #include "pdfpattern.h"
+#include "pdfcms.h"
 
 #include <QPainter>
 
@@ -389,6 +390,20 @@ void PDFPainter::setCompositionMode(QPainter::CompositionMode mode)
     m_painter->setCompositionMode(mode);
 }
 
+PDFPrecompiledPageGenerator::PDFPrecompiledPageGenerator(PDFPrecompiledPage* precompiledPage,
+                                                         PDFRenderer::Features features,
+                                                         const PDFPage* page,
+                                                         const PDFDocument* document,
+                                                         const PDFFontCache* fontCache,
+                                                         const PDFCMS* cms,
+                                                         const PDFOptionalContentActivity* optionalContentActivity,
+                                                         const PDFMeshQualitySettings& meshQualitySettings) :
+    BaseClass(features, page, document, fontCache, cms, optionalContentActivity, QMatrix(), meshQualitySettings),
+    m_precompiledPage(precompiledPage)
+{
+    m_precompiledPage->setPaperColor(cms->getPaperColor());
+}
+
 void PDFPrecompiledPageGenerator::performPathPainting(const QPainterPath& path, bool stroke, bool fill, bool text, Qt::FillRule fillRule)
 {
     Q_ASSERT(stroke || fill);
@@ -632,6 +647,38 @@ void PDFPrecompiledPage::optimize()
     m_compositionModes.shrink_to_fit();
 }
 
+void PDFPrecompiledPage::invertColors()
+{
+    // Jakub Melka: we must invert colors in following areas:
+    //     - painter paths
+    //     - images
+    //     - meshes
+
+    for (PathPaintData& pathData : m_paths)
+    {
+        if (pathData.pen.style() != Qt::NoPen)
+        {
+            pathData.pen.setColor(invertColor(pathData.pen.color()));
+        }
+        if (pathData.brush.style() == Qt::SolidPattern)
+        {
+            pathData.brush.setColor(invertColor(pathData.brush.color()));
+        }
+    }
+
+    for (ImageData& imageData : m_images)
+    {
+        imageData.image.invertPixels(QImage::InvertRgb);
+    }
+
+    for (MeshPaintData& meshPaintData : m_meshes)
+    {
+        meshPaintData.mesh.invertColors();
+    }
+
+    m_paperColor = invertColor(m_paperColor);
+}
+
 void PDFPrecompiledPage::finalize(qint64 compilingTimeNS, QList<PDFRenderError> errors)
 {
     m_compilingTimeNS = compilingTimeNS;

PdfForQtLib/sources/pdfpainter.h

@@ -199,6 +199,9 @@ public:
     /// Optimizes page memory allocation to contain less space
     void optimize();
 
+    /// Inverts all colors
+    void invertColors();
+
     /// Finalizes precompiled page
     /// \param compilingTimeNS Compiling time in nanoseconds
     /// \param errors List of rendering errors
@@ -216,6 +219,10 @@ public:
     /// Returns memory consumption estimate
     qint64 getMemoryConsumptionEstimate() const { return m_memoryConsumptionEstimate; }
 
+    /// Returns paper color
+    QColor getPaperColor() const { return m_paperColor; }
+    void setPaperColor(QColor paperColor) { m_paperColor = paperColor; }
+
 private:
     struct PathPaintData
     {
@@ -275,6 +282,7 @@ private:
 
     qint64 m_compilingTimeNS = 0;
     qint64 m_memoryConsumptionEstimate = 0;
+    QColor m_paperColor = QColor(Qt::white);
     std::vector<Instruction> m_instructions;
     std::vector<PathPaintData> m_paths;
     std::vector<ClipData> m_clips;
@@ -287,7 +295,7 @@ private:
 
 /// Processor, which processes PDF's page commands and writes them to the precompiled page.
 /// Precompiled page then can be used to execute these commands on QPainter.
-class PDFPrecompiledPageGenerator : public PDFPainterBase
+class PDFFORQTLIBSHARED_EXPORT PDFPrecompiledPageGenerator : public PDFPainterBase
 {
     using BaseClass = PDFPainterBase;
 
@@ -299,12 +307,7 @@ public:
                                                 const PDFFontCache* fontCache,
                                                 const PDFCMS* cms,
                                                 const PDFOptionalContentActivity* optionalContentActivity,
-                                                const PDFMeshQualitySettings& meshQualitySettings) :
-        BaseClass(features, page, document, fontCache, cms, optionalContentActivity, QMatrix(), meshQualitySettings),
-        m_precompiledPage(precompiledPage)
-    {
-
-    }
+                                                const PDFMeshQualitySettings& meshQualitySettings);
 
 protected:
     virtual void performPathPainting(const QPainterPath& path, bool stroke, bool fill, bool text, Qt::FillRule fillRule) override;

PdfForQtLib/sources/pdfpattern.cpp

@@ -1106,6 +1106,16 @@ qint64 PDFMesh::getMemoryConsumptionEstimate() const
     return memoryConsumption;
 }
 
+void PDFMesh::invertColors()
+{
+    for (Triangle& triangle : m_triangles)
+    {
+        triangle.color = 0x00FFFFFF - triangle.color;
+    }
+
+    m_backgroundColor = invertColor(m_backgroundColor);
+}
+
 void PDFMeshQualitySettings::initResolution()
 {
     Q_ASSERT(deviceSpaceMeshingArea.isValid());

PdfForQtLib/sources/pdfpattern.h

@@ -143,6 +143,9 @@ public:
     /// Returns estimate of number of bytes, which this mesh occupies in memory
     qint64 getMemoryConsumptionEstimate() const;
 
+    /// Invert colors
+    void invertColors();
+
 private:
     std::vector<QPointF> m_vertices;
     std::vector<Triangle> m_triangles;

PdfForQtLib/sources/pdfrenderer.cpp

@@ -144,6 +144,12 @@ void PDFRenderer::compile(PDFPrecompiledPage* precompiledPage, size_t pageIndex)
 
     PDFPrecompiledPageGenerator generator(precompiledPage, m_features, page, m_document, m_fontCache, m_cms, m_optionalContentActivity, m_meshQualitySettings);
     QList<PDFRenderError> errors = generator.processContents();
+
+    if (m_features.testFlag(InvertColors))
+    {
+        precompiledPage->invertColors();
+    }
+
     precompiledPage->optimize();
     precompiledPage->finalize(timer.nsecsElapsed(), qMove(errors));
     timer.invalidate();
@@ -214,7 +220,7 @@ QImage PDFRasterizer::render(const PDFPage* page, const PDFPrecompiledPage* comp
                 {
                     QOpenGLPaintDevice device(size);
                     QPainter painter(&device);
-                    painter.fillRect(QRect(QPoint(0, 0), size), Qt::white);
+                    painter.fillRect(QRect(QPoint(0, 0), size), compiledPage->getPaperColor());
                     compiledPage->draw(&painter, page->getCropBox(), matrix, features);
                 }
 

PdfForQtLib/sources/pdfrenderer.h

@@ -50,7 +50,8 @@ public:
         ClipToCropBox           = 0x0010,   ///< Clip page content to crop box (items outside crop box will not be visible)
         DisplayTimes            = 0x0020,   ///< Display page compile/draw time
         DebugTextBlocks         = 0x0040,   ///< Debug text block layout algorithm
-        DebugTextLines          = 0x0080    ///< Debug text line layout algorithm
+        DebugTextLines          = 0x0080,   ///< Debug text line layout algorithm
+        InvertColors            = 0x0100,   ///< Invert colors
     };
 
     Q_DECLARE_FLAGS(Features, Feature)

PdfForQtLib/sources/pdfutils.h

@@ -22,6 +22,7 @@
 #include "pdfglobal.h"
 
 #include <QRectF>
+#include <QColor>
 #include <QByteArray>
 #include <QDataStream>
 
@@ -429,6 +430,21 @@ constexpr bool isRectangleHorizontallyOverlapped(const QRectF& r1, const QRectF&
     return isIntervalOverlap(r1.left(), r1.right(), r2.left(), r2.right());
 }
 
+inline QColor invertColor(QColor color)
+{
+    qreal r = 0.0;
+    qreal g = 0.0;
+    qreal b = 0.0;
+    qreal a = 0.0;
+
+    color.getRgbF(&r, &g, &b, &a);
+
+    r = 1.0 - r;
+    g = 1.0 - g;
+    b = 1.0 - b;
+    return QColor::fromRgbF(r, g, b, a);
+}
+
 }   // namespace pdf
 
 #endif // PDFUTILS_H

PdfForQtViewer/pdfviewermainwindow.cpp

@@ -212,6 +212,7 @@ PDFViewerMainWindow::PDFViewerMainWindow(QWidget* parent) :
     ui->actionRenderOptionTextAntialiasing->setData(pdf::PDFRenderer::TextAntialiasing);
     ui->actionRenderOptionSmoothPictures->setData(pdf::PDFRenderer::SmoothImages);
     ui->actionRenderOptionIgnoreOptionalContentSettings->setData(pdf::PDFRenderer::IgnoreOptionalContent);
+    ui->actionInvertColors->setData(pdf::PDFRenderer::InvertColors);
     ui->actionShow_Text_Blocks->setData(pdf::PDFRenderer::DebugTextBlocks);
     ui->actionShow_Text_Lines->setData(pdf::PDFRenderer::DebugTextLines);
 
@@ -970,7 +971,8 @@ std::vector<QAction*> PDFViewerMainWindow::getRenderingOptionActions() const
              ui->actionRenderOptionSmoothPictures,
              ui->actionRenderOptionIgnoreOptionalContentSettings,
              ui->actionShow_Text_Blocks,
-             ui->actionShow_Text_Lines };
+             ui->actionShow_Text_Lines,
+             ui->actionInvertColors };
 }
 
 QList<QAction*> PDFViewerMainWindow::getActions() const

PdfForQtViewer/pdfviewermainwindow.ui

@@ -74,6 +74,8 @@
     <addaction name="actionFitPage"/>
     <addaction name="actionFitWidth"/>
     <addaction name="actionFitHeight"/>
+    <addaction name="separator"/>
+    <addaction name="actionInvertColors"/>
    </widget>
    <widget class="QMenu" name="menuTools">
     <property name="title">
@@ -409,6 +411,14 @@
     <string>Copy text</string>
    </property>
   </action>
+  <action name="actionInvertColors">
+   <property name="checkable">
+    <bool>true</bool>
+   </property>
+   <property name="text">
+    <string>Invert Colors</string>
+   </property>
+  </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
  <resources>