Improves image panning and zoom. Image view is now on a better default and usability.

8 files changed, 217 insertions, 11 deletions

diff --git a/Changelog.txt b/Changelog.txt
index a0a544e..23e5af8 100644
--- a/Changelog.txt
+++ b/Changelog.txt
@@ -28,7 +28,7 @@ Kristall Changelog
   - Added possibility to open links into a new tab
   - Added possibility to open history and favourite items into new tab or same tab
 - Added option to use your default OS protocol handler instead of displaying an error message.
-- 
+- Improved image pan and zooming. Explore those graphics!
 
 == 0.1
 - Initial release
\ No newline at end of file
diff --git a/README.md b/README.md
index 297bb80..8800e46 100644
--- a/README.md
+++ b/README.md
@@ -106,8 +106,6 @@ ln -s Kristall.desktop ~/.local/share/applications/kristall.desktop
 - [ ] Implement more protocols
   - [ ] Gopher
     - [ ] Support more media types (include uudecode and hexbin decoder)
-    - [x] Read non-binary media only until `.`
-- [ ] Image Zoom and Pan
   
 ### 0.3 release
 - [ ] TLS Handling
diff --git a/lib/luis-l-gist/interactiveview.cpp b/lib/luis-l-gist/interactiveview.cpp
new file mode 100644
index 0000000..2707352
--- /dev/null
+++ b/lib/luis-l-gist/interactiveview.cpp
@@ -0,0 +1,133 @@
+#include "interactiveview.hpp"
+
+#define VIEW_CENTER viewport()->rect().center()
+#define VIEW_WIDTH viewport()->rect().width()
+#define VIEW_HEIGHT viewport()->rect().height()
+
+InteractiveView::InteractiveView(QWidget * parent) :
+    QGraphicsView(parent)
+{
+    setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+    setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+
+    setMaxSize();
+    centerOn(0, 0);
+
+    zoomDelta = 0.1;
+    panSpeed = 4;
+    _doMousePanning = false;
+    _doKeyZoom = false;
+    _scale = 1.0;
+
+    panButton = Qt::MiddleButton;
+    zoomKey = Qt::Key_Z;
+}
+
+qreal InteractiveView::getScale() const
+{
+    return _scale;
+}
+
+void InteractiveView::keyPressEvent(QKeyEvent * event)
+{
+    qint32 key = event->key();
+
+    if(key == zoomKey){
+        _doKeyZoom = true;
+    }
+
+    if (_doKeyZoom){
+        if (key == Qt::Key_Up)
+            zoomIn();
+
+        else if (key == Qt::Key_Down)
+            zoomOut();
+    }
+
+    else{
+        QGraphicsView::keyPressEvent(event);
+    }
+}
+
+void InteractiveView::keyReleaseEvent(QKeyEvent * event)
+{
+    if (event->key() == zoomKey){
+        _doKeyZoom = false;
+    }
+
+    QGraphicsView::keyReleaseEvent(event);
+}
+
+void InteractiveView::mouseMoveEvent(QMouseEvent * event)
+{
+    if (_doMousePanning){
+        QPointF mouseDelta = mapToScene(event->pos()) - mapToScene(_lastMousePos);
+        pan(mouseDelta);
+    }
+
+    QGraphicsView::mouseMoveEvent(event);
+    _lastMousePos = event->pos();
+}
+
+void InteractiveView::mousePressEvent(QMouseEvent * event)
+{
+    if (event->button() == panButton){
+        _lastMousePos = event->pos();
+        _doMousePanning = true;
+    }
+
+    QGraphicsView::mousePressEvent(event);
+}
+
+void InteractiveView::mouseReleaseEvent(QMouseEvent * event)
+{
+    if (event->button() == panButton){
+        _doMousePanning = false;
+    }
+
+    QGraphicsView::mouseReleaseEvent(event);
+}
+
+void InteractiveView::wheelEvent(QWheelEvent *event)
+{
+    QPoint scrollAmount = event->angleDelta();
+
+    // Apply zoom.
+    scrollAmount.y() > 0 ? zoomIn() : zoomOut();
+}
+
+void InteractiveView::setMaxSize()
+{
+    setSceneRect(INT_MIN/2, INT_MIN/2, INT_MAX, INT_MAX);
+}
+
+void InteractiveView::zoom(float scaleFactor)
+{
+    scale(scaleFactor, scaleFactor);
+    _scale *= scaleFactor;
+}
+
+void InteractiveView::zoomIn()
+{
+    zoom(1 + zoomDelta);
+}
+
+void InteractiveView::zoomOut()
+{
+    zoom (1 - zoomDelta);
+}
+
+void InteractiveView::pan(QPointF delta)
+{
+    // Scale the pan amount by the current zoom.
+    delta *= _scale;
+    delta *= panSpeed;
+
+    // Have panning be anchored from the mouse.
+    setTransformationAnchor(QGraphicsView::AnchorUnderMouse);
+    QPoint newCenter(VIEW_WIDTH / 2 - delta.x(),  VIEW_HEIGHT / 2 - delta.y());
+    centerOn(mapToScene(newCenter));
+
+    // For zooming to anchor from the view center.
+    setTransformationAnchor(QGraphicsView::AnchorViewCenter);
+}
diff --git a/lib/luis-l-gist/interactiveview.hpp b/lib/luis-l-gist/interactiveview.hpp
new file mode 100644
index 0000000..1a0b1f8
--- /dev/null
+++ b/lib/luis-l-gist/interactiveview.hpp
@@ -0,0 +1,47 @@
+#ifndef INTERACTIVE_VIEW_H
+#define INTERACTIVE_VIEW_H
+
+#include <QGraphicsView>
+#include <QWheelEvent>
+#include <QKeyEvent>
+
+class InteractiveView : public QGraphicsView
+{
+public:
+    explicit InteractiveView(QWidget * parent);
+
+    qreal panSpeed;
+    qreal zoomDelta;
+    qreal zoomKey;
+    Qt::MouseButton panButton;
+
+    void pan(QPointF delta);
+    void zoom(float scaleFactor);
+    void zoomIn();
+    void zoomOut();
+
+    qreal getScale() const;
+
+protected:
+
+    void keyPressEvent(QKeyEvent*) override;
+    void keyReleaseEvent(QKeyEvent*) override;
+
+    void mouseMoveEvent(QMouseEvent*) override;
+    void mousePressEvent(QMouseEvent*) override;
+    void mouseReleaseEvent(QMouseEvent*) override;
+    void wheelEvent(QWheelEvent*) override;
+
+private:
+
+    // Flags to determine if zooming or panning should be done.
+    bool _doMousePanning;
+    bool _doKeyZoom;
+
+    QPoint _lastMousePos;
+    qreal _scale;
+
+    void setMaxSize();
+};
+
+#endif // INTERACTIVE_VIEW_H
diff --git a/src/browsertab.cpp b/src/browsertab.cpp
index 086af38..d9f2ffa 100644
--- a/src/browsertab.cpp
+++ b/src/browsertab.cpp
@@ -21,6 +21,7 @@
 #include <QFile>
 #include <QMimeDatabase>
 #include <QMimeType>
+#include <QImageReader>
 
 #include <QGraphicsPixmapItem>
 #include <QGraphicsTextItem>
@@ -65,8 +66,6 @@ BrowserTab::BrowserTab(MainWindow * mainWindow) :
     this->ui->text_browser->setVisible(true);
 
     this->ui->text_browser->setContextMenuPolicy(Qt::CustomContextMenu);
-
-    this->ui->graphics_browser->setScene(&graphics_scene);
 }
 
 BrowserTab::~BrowserTab()
@@ -337,16 +336,34 @@ void BrowserTab::on_requestComplete(const QByteArray &data, const QString &mime)
     else if(mime.startsWith("image/")) {
         doc_type = Image;
 
+        QBuffer buffer;
+        buffer.setData(data);
+
+        QImageReader reader { &buffer };
+        reader.setAutoTransform(true);
+        reader.setAutoDetectImageFormat(true);
+
+
         QImage img;
-        if(img.loadFromData(data, nullptr))
+        if(reader.read(&img))
         {
-            this->graphics_scene.addPixmap(QPixmap::fromImage(img));
+            auto pixmap = QPixmap::fromImage(img);
+            this->graphics_scene.addPixmap(pixmap);
+            this->graphics_scene.setSceneRect(pixmap.rect());
         }
         else
         {
-            this->graphics_scene.addText("Failed to load picture!");
+            this->graphics_scene.addText(QString("Failed to load picture:\r\n%1").arg(reader.errorString()));
         }
 
+        this->ui->graphics_browser->setScene(&graphics_scene);
+
+        auto * invoker = new QObject();
+        connect(invoker, &QObject::destroyed, [this]() {
+            this->ui->graphics_browser->fitInView(graphics_scene.sceneRect(), Qt::KeepAspectRatio);
+        });
+        invoker->deleteLater();
+
         this->ui->graphics_browser->fitInView(graphics_scene.sceneRect(), Qt::KeepAspectRatio);
     }
     else if(mime.startsWith("video/") or mime.startsWith("audio/")) {
diff --git a/src/browsertab.ui b/src/browsertab.ui
index 6903bd8..7be4d3c 100644
--- a/src/browsertab.ui
+++ b/src/browsertab.ui
@@ -164,7 +164,10 @@ p, li { white-space: pre-wrap; }
       </widget>
      </item>
      <item>
-      <widget class="QGraphicsView" name="graphics_browser">
+      <widget class="InteractiveView" name="graphics_browser">
+       <property name="interactive">
+        <bool>true</bool>
+       </property>
        <property name="dragMode">
         <enum>QGraphicsView::ScrollHandDrag</enum>
        </property>
@@ -190,6 +193,11 @@ p, li { white-space: pre-wrap; }
    <header>mediaplayer.hpp</header>
    <container>1</container>
   </customwidget>
+  <customwidget>
+   <class>InteractiveView</class>
+   <extends>QGraphicsView</extends>
+   <header location="global">interactiveview.hpp</header>
+  </customwidget>
  </customwidgets>
  <resources>
   <include location="icons.qrc"/>
diff --git a/src/gophermaprenderer.cpp b/src/gophermaprenderer.cpp
index 89f3905..e2fe434 100644
--- a/src/gophermaprenderer.cpp
+++ b/src/gophermaprenderer.cpp
@@ -137,8 +137,6 @@ std::unique_ptr<QTextDocument> GophermapRenderer::render(const QByteArray &input
 
         QString title = items.at(0);
 
-        // 1Phlog	/phlog	octotherp.org	70	+
-
         if (type == 'i')
         {
             cursor.insertText(title + "\n", standard);
diff --git a/src/kristall.pro b/src/kristall.pro
index dc69b8b..0321179 100644
--- a/src/kristall.pro
+++ b/src/kristall.pro
@@ -18,7 +18,11 @@ DEFINES += QT_DEPRECATED_WARNINGS
 QMAKE_CFLAGS += -Wno-unused-parameter
 QMAKE_CXXFLAGS += -Wno-unused-parameter
 
+INCLUDEPATH += $$PWD/../lib/luis-l-gist/
+DEPENDPATH += $$PWD/../lib/luis-l-gist/
+
 SOURCES += \
+    ../lib/luis-l-gist/interactiveview.cpp \
     browsertab.cpp \
     documentoutlinemodel.cpp \
     documentstyle.cpp \
@@ -39,6 +43,7 @@ SOURCES += \
     webclient.cpp
 
 HEADERS += \
+    ../lib/luis-l-gist/interactiveview.hpp \
     browsertab.hpp \
     documentoutlinemodel.hpp \
     documentstyle.hpp \