viewer: provide UI to set preview resolution

Previews don't need to be rendered full resolution, particularly since the
preview is hardly ever 1:1 size of the sequence. The functionality to render
at lower resolutions already existed, but there was no UI for it. This commit
implements UI to set the resolution divider on the viewer.

app/widget/viewer/viewer.cpp

@@ -32,11 +32,14 @@
 #include "project/item/sequence/sequence.h"
 #include "project/project.h"
 #include "render/pixelservice.h"
+#include "widget/menu/menu.h"
 
 ViewerWidget::ViewerWidget(QWidget *parent) :
   QWidget(parent),
   viewer_node_(nullptr),
-  playback_speed_(0)
+  playback_speed_(0),
+  color_menu_enabled_(true),
+  divider_(Config::Current()["DefaultViewerDivider"].toInt())
 {
   // Set up main layout
   QVBoxLayout* layout = new QVBoxLayout(this);
@@ -47,6 +50,7 @@ ViewerWidget::ViewerWidget(QWidget *parent) :
   layout->addWidget(sizer_);
 
   gl_widget_ = new ViewerGLWidget();
+  connect(gl_widget_, &ViewerGLWidget::customContextMenuRequested, this, &ViewerWidget::ShowContextMenu);
   sizer_->SetWidget(gl_widget_);
 
   // Create time ruler
@@ -190,7 +194,7 @@ ViewerOutput *ViewerWidget::GetConnectedViewer() const
 
 void ViewerWidget::SetColorMenuEnabled(bool enabled)
 {
-  gl_widget_->SetColorMenuEnabled(enabled);
+  color_menu_enabled_ = enabled;
 }
 
 void ViewerWidget::SetOverrideSize(int width, int height)
@@ -297,13 +301,74 @@ void ViewerWidget::UpdateRendererParameters()
   video_renderer_->SetParameters(VideoRenderingParams(viewer_node_->video_params(),
                                                       PixelService::instance()->GetConfiguredFormatForMode(render_mode),
                                                       render_mode,
-                                                      2));
+                                                      divider_));
   audio_renderer_->SetParameters(AudioRenderingParams(viewer_node_->audio_params(),
                                                       SampleFormat::GetConfiguredFormatForMode(render_mode)));
 
   video_renderer_->InvalidateCache(0, viewer_node_->Length());
 }
 
+void ViewerWidget::ShowContextMenu(const QPoint &pos)
+{
+  QMenu menu;
+
+  // Color options
+  if (gl_widget_->color_manager() && color_menu_enabled_) {
+    QStringList displays = gl_widget_->color_manager()->ListAvailableDisplays();
+    QMenu* ocio_display_menu = menu.addMenu(tr("Display"));
+    connect(ocio_display_menu, &QMenu::triggered, this, &ViewerWidget::ColorDisplayChanged);
+    foreach (const QString& d, displays) {
+      QAction* action = ocio_display_menu->addAction(d);
+      action->setCheckable(true);
+      action->setChecked(gl_widget_->ocio_display() == d);
+      action->setData(d);
+    }
+
+    QStringList views = gl_widget_->color_manager()->ListAvailableViews(gl_widget_->ocio_display());
+    QMenu* ocio_view_menu = menu.addMenu(tr("View"));
+    connect(ocio_view_menu, &QMenu::triggered, this, &ViewerWidget::ColorViewChanged);
+    foreach (const QString& v, views) {
+      QAction* action = ocio_view_menu->addAction(v);
+      action->setCheckable(true);
+      action->setChecked(gl_widget_->ocio_view() == v);
+      action->setData(v);
+    }
+
+    QStringList looks = gl_widget_->color_manager()->ListAvailableLooks();
+    QMenu* ocio_look_menu = menu.addMenu(tr("Look"));
+    connect(ocio_look_menu, &QMenu::triggered, this, &ViewerWidget::ColorLookChanged);
+    QAction* no_look_action = ocio_look_menu->addAction(tr("(None)"));
+    no_look_action->setCheckable(true);
+    no_look_action->setChecked(gl_widget_->ocio_look().isEmpty());
+    foreach (const QString& l, looks) {
+      QAction* action = ocio_look_menu->addAction(l);
+      action->setCheckable(true);
+      action->setChecked(gl_widget_->ocio_look() == l);
+      action->setData(l);
+    }
+
+    menu.addSeparator();
+  }
+
+  // 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);
+  connect(playback_resolution_menu, &QMenu::triggered, this, &ViewerWidget::SetDividerFromMenu);
+
+  foreach (QAction* a, playback_resolution_menu->actions()) {
+    a->setCheckable(true);
+    if (a->data() == divider_) {
+      a->setChecked(true);
+    }
+  }
+
+  menu.exec(mapToGlobal(pos));
+}
+
 void ViewerWidget::RulerTimeChange(int64_t i)
 {
   Pause();
@@ -461,3 +526,32 @@ void ViewerWidget::resizeEvent(QResizeEvent *event)
   // Set scrollbar page step to the width
   scrollbar_->setPageStep(event->size().width());
 }
+
+void ViewerWidget::ColorDisplayChanged(QAction* action)
+{
+  SetOCIODisplay(action->data().toString());
+}
+
+void ViewerWidget::ColorViewChanged(QAction *action)
+{
+  SetOCIOView(action->data().toString());
+}
+
+void ViewerWidget::ColorLookChanged(QAction *action)
+{
+  SetOCIOLook(action->data().toString());
+}
+
+void ViewerWidget::SetDividerFromMenu(QAction *action)
+{
+  int divider = action->data().toInt();
+
+  if (divider <= 0) {
+    qWarning() << "Tried to set invalid divider:" << divider;
+    return;
+  }
+
+  divider_ = divider;
+
+  UpdateRendererParameters();
+}