started timeruler object

app/widget/timeruler/CMakeLists.txt

@@ -0,0 +1,22 @@
+# 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/timeruler/timeruler.h
+  widget/timeruler/timeruler.cpp
+  PARENT_SCOPE
+)

app/widget/timeruler/timeruler.cpp

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+#include "timeruler.h"
+
+#include <QPainter>
+
+#include "common/qtversionabstraction.h"
+
+TimeRuler::TimeRuler(bool text_visible, QWidget* parent) :
+  QWidget(parent),
+  scroll_(0),
+  scale_(1.0)
+{
+  // Text height is used to calculate widget height
+  text_height_ = fontMetrics().height();
+
+  // FIXME: Fairly mediocre, but reliable way of scaling UI objects by font/DPI size
+  QFontMetrics fm = fontMetrics();
+  width_of_second_ = QFontMetricsWidth(&fm, "HHHHHHHHHHHHHHHH");
+  minimum_gap_between_lines_ = QFontMetricsWidth(&fm, "HH");
+
+  SetTextVisible(text_visible);
+}
+
+void TimeRuler::SetTextVisible(bool e)
+{
+  text_visible_ = e;
+
+  if (text_visible_) {
+    setMinimumHeight(text_height_ * 2);
+  } else {
+    setMinimumHeight(text_height_);
+  }
+
+  update();
+}
+
+void TimeRuler::SetScale(double d)
+{
+  scale_ = d;
+
+  update();
+}
+
+void TimeRuler::SetTimebase(const rational &r)
+{
+  time_base_ = r;
+
+  update();
+}
+
+void TimeRuler::paintEvent(QPaintEvent *e)
+{
+  Q_UNUSED(e)
+
+  QPainter p(this);
+
+  // FIXME: Make this CSS configurable
+  p.setPen(Qt::white);
+
+  // Calculate where the ruler lines should be
+  int ruler_second_line_top = 0;
+  int ruler_second_line_bottom = height();
+
+  //int ruler_frame_line_top = (text_visible_) ? text_height_ : 0;
+  //int ruler_frame_line_bottom = height();
+
+  // Get scaled width of a second
+  double scaled_width = width_of_second_ * scale_;
+
+  // Draw a line for each second
+  int last_draw = -1;
+  for (double i=0;i<width();i+=scaled_width) {
+
+    // Ensure a reasonable gap has been left between the last line drawn and the line we're about to draw
+    int line_x = qRound(i);
+    if (last_draw < 0 || line_x - last_draw > minimum_gap_between_lines_) {
+
+      p.drawLine(line_x, ruler_second_line_top, line_x, ruler_second_line_bottom);
+
+      p.drawText(line_x, p.fontMetrics().ascent(), QString::number(line_x));
+
+      last_draw = line_x;
+    }
+  }
+}

app/widget/timeruler/timeruler.h

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+#ifndef TIMERULER_H
+#define TIMERULER_H
+
+#include <QWidget>
+
+#include "common/rational.h"
+
+class TimeRuler : public QWidget
+{
+  Q_OBJECT
+public:
+  TimeRuler(bool text_visible = true, QWidget* parent = nullptr);
+
+  void SetTextVisible(bool e);
+
+  void SetScale(double d);
+
+  void SetTimebase(const rational& r);
+
+protected:
+  virtual void paintEvent(QPaintEvent* e) override;
+
+private:
+  int text_height_;
+
+  int width_of_second_;
+
+  int minimum_gap_between_lines_;
+
+  int scroll_;
+
+  bool text_visible_;
+
+  double scale_;
+
+  rational time_base_;
+};
+
+#endif // TIMERULER_H