viewer: implemented basic zoom

No scrolling functionality yet, but the zoom is functional and efficient.

app/widget/viewer/viewer.cpp

@@ -57,11 +57,11 @@ ViewerWidget::ViewerWidget(QWidget *parent) :
 
   gl_widget_ = new ViewerGLWidget();
   connect(gl_widget_, &ViewerGLWidget::customContextMenuRequested, this, &ViewerWidget::ShowContextMenu);
+  connect(sizer_, &ViewerSizer::RequestMatrix, gl_widget_, &ViewerGLWidget::SetMatrix);
   sizer_->SetWidget(gl_widget_);
 
   // Create waveform view when audio is connected and video isn't
   waveform_view_ = new WaveformView();
-
   stack_->addWidget(waveform_view_);
 
   // Create time ruler
@@ -272,7 +272,7 @@ void ViewerWidget::PlayInternal(int speed)
 
   controls_->ShowPauseButton();
 
-  if (stack_->currentWidget() == gl_widget_) {
+  if (stack_->currentWidget() == sizer_) {
     connect(gl_widget_, &ViewerGLWidget::frameSwapped, this, &ViewerWidget::PlaybackTimerUpdate);
   } else {
     connect(AudioManager::instance(), &AudioManager::OutputNotified, this, &ViewerWidget::PlaybackTimerUpdate);
@@ -315,7 +315,7 @@ int ViewerWidget::CalculateDivider()
 void ViewerWidget::UpdateStack()
 {
   if (!GetConnectedNode() || GetConnectedNode()->texture_input()->IsConnected()) {
-    stack_->setCurrentWidget(gl_widget_);
+    stack_->setCurrentWidget(sizer_);
   } else {
     stack_->setCurrentWidget(waveform_view_);
   }
@@ -393,12 +393,21 @@ void ViewerWidget::ShowContextMenu(const QPoint &pos)
   // Playback resolution
   QMenu* playback_resolution_menu = menu.addMenu(tr("Resolution"));
   playback_resolution_menu->addAction(tr("Full"))->setData(1);
-  playback_resolution_menu->addAction(tr("1/2"))->setData(2);
-  playback_resolution_menu->addAction(tr("1/4"))->setData(4);
-  playback_resolution_menu->addAction(tr("1/8"))->setData(8);
-  playback_resolution_menu->addAction(tr("1/16"))->setData(16);
+  int dividers[] = {2, 4, 8, 16};
+  for (int i=0;i<4;i++) {
+    playback_resolution_menu->addAction(tr("1/%1").arg(dividers[i]))->setData(dividers[i]);
+  }
   connect(playback_resolution_menu, &QMenu::triggered, this, &ViewerWidget::SetDividerFromMenu);
 
+  // Viewer Zoom Level
+  QMenu* zoom_menu = menu.addMenu(tr("Zoom"));
+  int zoom_levels[] = {10, 25, 50, 75, 100, 150, 200, 400};
+  zoom_menu->addAction(tr("Fit"))->setData(0);
+  for (int i=0;i<8;i++) {
+    zoom_menu->addAction(tr("%1%").arg(zoom_levels[i]))->setData(zoom_levels[i]);
+  }
+  connect(zoom_menu, &QMenu::triggered, this, &ViewerWidget::SetZoomFromMenu);
+
   foreach (QAction* a, playback_resolution_menu->actions()) {
     a->setCheckable(true);
     if (a->data() == divider_) {
@@ -564,6 +573,11 @@ void ViewerWidget::SetDividerFromMenu(QAction *action)
   UpdateRendererParameters();
 }
 
+void ViewerWidget::SetZoomFromMenu(QAction *action)
+{
+  sizer_->SetZoom(action->data().toInt());
+}
+
 void ViewerWidget::InvalidateVisible()
 {
   video_renderer_->InvalidateCache(TimeRange(GetTime(), GetTime()));

app/widget/viewer/viewer.h

@@ -187,6 +187,8 @@ private slots:
 
   void SetDividerFromMenu(QAction* action);
 
+  void SetZoomFromMenu(QAction* action);
+
   void InvalidateVisible();
 
   void UpdateStack();

app/widget/viewer/viewerglwidget.h

@@ -68,18 +68,17 @@ public:
    */
   void DisconnectColorManager();
 
-  /**
-   * @brief Set the transformation matrix to draw with
-   *
-   * Set this if you want the drawing to pass through some sort of transform (most of the time you won't want this).
-   */
-  void SetMatrix(const QMatrix4x4& mat);
-
   /**
    * @brief Set an image to load and display on screen
    */
   void SetImage(const QString& fn);
 
+  ColorManager* color_manager() const;
+
+  const QString& ocio_display() const;
+  const QString& ocio_view() const;
+  const QString& ocio_look() const;
+
 public slots:
   /**
    * @brief Set the texture to draw and draw it
@@ -113,11 +112,12 @@ public slots:
    */
   void SetOCIOLook(const QString& look);
 
-  ColorManager* color_manager() const;
-
-  const QString& ocio_display() const;
-  const QString& ocio_view() const;
-  const QString& ocio_look() const;
+  /**
+   * @brief Set the transformation matrix to draw with
+   *
+   * Set this if you want the drawing to pass through some sort of transform (most of the time you won't want this).
+   */
+  void SetMatrix(const QMatrix4x4& mat);
 
 signals:
   void DragStarted();

app/widget/viewer/viewersizer.cpp

@@ -1,9 +1,12 @@
 #include "viewersizer.h"
 
+#include <QMatrix4x4>
+
 ViewerSizer::ViewerSizer(QWidget *parent) :
   QWidget(parent),
   widget_(nullptr),
-  aspect_ratio_(0)
+  aspect_ratio_(0),
+  zoom_(0)
 {
 }
 
@@ -23,15 +26,25 @@ void ViewerSizer::SetWidget(QWidget *widget)
 
 void ViewerSizer::SetChildSize(int width, int height)
 {
-  if (height == 0) {
+  width_ = width;
+  height_ = height;
+
+  if (!width_ || !height_) {
     aspect_ratio_ = 0;
   } else {
-    aspect_ratio_ = static_cast<double>(width) / static_cast<double>(height);
+    aspect_ratio_ = static_cast<double>(width_) / static_cast<double>(height_);
   }
 
   UpdateSize();
 }
 
+void ViewerSizer::SetZoom(int percent)
+{
+  zoom_ = percent;
+
+  UpdateSize();
+}
+
 void ViewerSizer::resizeEvent(QResizeEvent *event)
 {
   QWidget::resizeEvent(event);
@@ -53,21 +66,51 @@ void ViewerSizer::UpdateSize()
 
   widget_->setVisible(true);
 
-  double our_aspect_ratio = static_cast<double>(width()) / static_cast<double>(height());
+  QSize child_size;
+  QMatrix4x4 child_matrix;
 
-  QPoint child_pos;
-  QSize child_size = size();
+  if (zoom_ <= 0) {
+
+    // If zoom is 0, we auto-fit
+    double our_aspect_ratio = static_cast<double>(width()) / static_cast<double>(height());
+
+    child_size = size();
+
+    if (our_aspect_ratio > aspect_ratio_) {
+      // This container is wider than the image, scale by height
+      child_size = QSize(qRound(child_size.height() * aspect_ratio_), height());
+    } else {
+      // This container is taller than the image, scale by width
+      child_size = QSize(width(), qRound(child_size.width() / aspect_ratio_));
+    }
 
-  if (our_aspect_ratio > aspect_ratio_) {
-    // This container is wider than the image, scale by height
-    child_size.setWidth(qRound(child_size.height() * aspect_ratio_));
-    child_pos.setX(width() / 2 - child_size.width() / 2);
   } else {
-    // This container is taller than the image, scale by width
-    child_size.setHeight(qRound(child_size.width() / aspect_ratio_));
-    child_pos.setY(height() / 2 - child_size.height() / 2);
+
+    float x_scale = 1.0f;
+    float y_scale = 1.0f;
+
+    int zoomed_width = qRound(width_ * static_cast<double>(zoom_) * 0.01);
+    int zoomed_height = qRound(height_ * static_cast<double>(zoom_) * 0.01);
+
+    if (zoomed_width > width()) {
+      x_scale = static_cast<double>(zoomed_width) / static_cast<double>(width());
+      zoomed_width = width();
+    }
+
+    if (zoomed_height > height()) {
+      y_scale = static_cast<double>(zoomed_height) / static_cast<double>(height());
+      zoomed_height = height();
+    }
+
+    // Rather than make a huge surface, we still crop at our width/height and then signal a matrix
+    child_matrix.scale(x_scale, y_scale, 1.0F);
+
+    child_size = QSize(zoomed_width, zoomed_height);
+
   }
 
   widget_->resize(child_size);
-  widget_->move(child_pos);
+  widget_->move(width() / 2 - child_size.width() / 2, height() / 2 - child_size.height() / 2);
+
+  emit RequestMatrix(child_matrix);
 }

app/widget/viewer/viewersizer.h

@@ -52,6 +52,16 @@ public:
    */
   void SetChildSize(int width, int height);
 
+  /**
+   * @brief Set the zoom value of the child widget
+   *
+   * The number is an integer percentage (100 = 100%). Set to 0 to auto-fit.
+   */
+  void SetZoom(int percent);
+
+signals:
+  void RequestMatrix(const QMatrix4x4& matrix);
+
 protected:
   /**
    * @brief Listen for resize events to ensure the child widget remains correctly sized
@@ -71,11 +81,22 @@ private:
    */
   QWidget* widget_;
 
+  /**
+   * @brief Internal resolution values
+   */
+  int width_;
+  int height_;
+
   /**
    * @brief Aspect ratio calculated from the size provided by SetChildSize()
    */
   double aspect_ratio_;
 
+  /**
+   * @brief Internal zoom value
+   */
+  int zoom_;
+
 };
 
 #endif // VIEWERSIZER_H