began UI for keyframing

Largely extending the existing NodeParamView with functionality from the
previous release.

app/widget/keyframeview/CMakeLists.txt

@@ -0,0 +1,24 @@
+# Olive - Non-Linear Video Editor
+# Copyright (C) 2019 Olive Team
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+set(OLIVE_SOURCES
+  ${OLIVE_SOURCES}
+  widget/keyframeview/keyframeview.h
+  widget/keyframeview/keyframeview.cpp
+  widget/keyframeview/keyframeviewitem.h
+  widget/keyframeview/keyframeviewitem.cpp
+  PARENT_SCOPE
+)

app/widget/keyframeview/keyframeview.cpp

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+#include "keyframeview.h"
+
+#include <QVBoxLayout>
+
+KeyframeView::KeyframeView(QWidget *parent) :
+  QWidget(parent)
+{
+  QVBoxLayout* layout = new QVBoxLayout(this);
+  layout->setSpacing(0);
+  layout->setMargin(0);
+
+  ruler_ = new TimeRuler();
+  ruler_->SetTextVisible(true);
+  layout->addWidget(ruler_);
+
+  view_ = new QGraphicsView();
+  view_->setScene(&scene_);
+  view_->setBackgroundRole(QPalette::Base);
+  view_->setAlignment(Qt::AlignLeft | Qt::AlignTop);
+  view_->setDragMode(QGraphicsView::RubberBandDrag);
+  layout->addWidget(view_);
+}
+
+void KeyframeView::SetTimebase(const rational &timebase)
+{
+  ruler_->SetTimebase(timebase);
+}

app/widget/keyframeview/keyframeview.h

@@ -0,0 +1,26 @@
+#ifndef KEYFRAMEVIEW_H
+#define KEYFRAMEVIEW_H
+
+#include <QGraphicsView>
+
+#include "common/rational.h"
+#include "keyframeviewitem.h"
+#include "widget/timeruler/timeruler.h"
+
+class KeyframeView : public QWidget
+{
+public:
+  KeyframeView(QWidget* parent = nullptr);
+
+  void AddKeyframe(const rational& time, int y);
+
+  void SetTimebase(const rational& timebase);
+
+private:
+  TimeRuler* ruler_;
+  QGraphicsView* view_;
+
+  QGraphicsScene scene_;
+};
+
+#endif // KEYFRAMEVIEW_H

app/widget/keyframeview/keyframeviewitem.cpp

@@ -0,0 +1,83 @@
+#include "keyframeviewitem.h"
+
+#include <QApplication>
+#include <QPainter>
+#include <QStyleOptionGraphicsItem>
+#include <QWidget>
+
+#include "common/qtversionabstraction.h"
+
+KeyframeViewItem::KeyframeViewItem(QGraphicsItem *parent) :
+  QGraphicsRectItem(parent),
+  key_(nullptr),
+  scale_(1.0)
+{
+  keyframe_size_ = QFontMetricsWidth(qApp->fontMetrics(), "Oi");
+  setFlag(QGraphicsItem::ItemIsSelectable);
+  setFlag(QGraphicsItem::ItemIsMovable);
+}
+
+void KeyframeViewItem::SetKeyframe(NodeKeyframe *key)
+{
+  key_ = key;
+  UpdateRect();
+}
+
+void KeyframeViewItem::SetVerticalCenter(int middle)
+{
+  middle_ = middle;
+  UpdateRect();
+}
+
+void KeyframeViewItem::SetScale(double scale)
+{
+  scale_ = scale;
+  UpdateRect();
+}
+
+void KeyframeViewItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
+{
+  if (!key_) {
+    return;
+  }
+
+  painter->setPen(Qt::black);
+
+  if (option->state & QStyle::State_Selected) {
+    painter->setBrush(widget->palette().highlight());
+  } else {
+    painter->setBrush(widget->palette().text());
+  }
+
+  switch (key_->type()) {
+  case NodeKeyframe::kLinear:
+  {
+    QPointF points[] = {
+      QPointF(rect().center().x(), rect().top()),
+      QPointF(rect().right(), rect().center().y()),
+      QPointF(rect().center().x(), rect().bottom()),
+      QPointF(rect().left(), rect().center().y())
+    };
+
+    painter->drawPolygon(points, 4);
+    break;
+  }
+  case NodeKeyframe::kBezier:
+    painter->drawEllipse(rect());
+    break;
+  case NodeKeyframe::kHold:
+    painter->drawRect(rect());
+    break;
+  }
+}
+
+void KeyframeViewItem::UpdateRect()
+{
+  if (!key_) {
+    return;
+  }
+
+  double x_center = key_->time().toDouble() * scale_;
+
+  setRect(x_center - keyframe_size_/2, middle_ - keyframe_size_/2, keyframe_size_, keyframe_size_);
+}

app/widget/keyframeview/keyframeviewitem.h

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+#ifndef KEYFRAMEVIEWITEM_H
+#define KEYFRAMEVIEWITEM_H
+
+#include <QGraphicsRectItem>
+
+#include "node/keyframe.h"
+
+class KeyframeViewItem : public QGraphicsRectItem
+{
+public:
+  KeyframeViewItem(QGraphicsItem *parent = nullptr);
+
+  void SetKeyframe(NodeKeyframe* key);
+
+  void SetVerticalCenter(int middle);
+
+  void SetScale(double scale);
+
+protected:
+  virtual void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr) override;
+
+private:
+  void UpdateRect();
+
+  NodeKeyframe* key_;
+
+  double scale_;
+
+  int middle_;
+
+  int keyframe_size_;
+};
+
+#endif // KEYFRAMEVIEWITEM_H