Dive video: paint duration-bar above thumbnail in profile plot

Paint a rectangle on top of thumbnails indicating the run-time
of the video.

Use the z=100.0-101.0 range for painting the thumbnails, whereby
the z-value increases uniformly from first to last thumbnail
(sorted by timestamp). The duration-bars are placed at z-values
midway between those of the thumbnails.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

4 files changed, 103 insertions, 24 deletions

diff --git a/profile-widget/divepixmapitem.cpp b/profile-widget/divepixmapitem.cpp
index d295fb4dd..730cdf606 100644
--- a/profile-widget/divepixmapitem.cpp
+++ b/profile-widget/divepixmapitem.cpp
@@ -42,7 +42,8 @@ void CloseButtonItem::show()
 DivePictureItem::DivePictureItem(QGraphicsItem *parent): DivePixmapItem(parent),
 	canvas(new QGraphicsRectItem(this)),
 	shadow(new QGraphicsRectItem(this)),
-	button(new CloseButtonItem(this))
+	button(new CloseButtonItem(this)),
+	baseZValue(0.0)
 {
 	setFlag(ItemIgnoresTransformations);
 	setAcceptHoverEvents(true);
@@ -67,6 +68,14 @@ DivePictureItem::DivePictureItem(QGraphicsItem *parent): DivePixmapItem(parent),
 	button->hide();
 }
 
+// The base z-value is used for correct paint-order of the thumbnails. On hoverEnter the z-value is raised
+// so that the thumbnail is drawn on top of all other thumbnails and on hoverExit it is restored to the base value.
+void DivePictureItem::setBaseZValue(double z)
+{
+	baseZValue = z;
+	setZValue(z);
+}
+
 void DivePictureItem::settingsChanged()
 {
 	setVisible(prefs.show_pictures_in_profile);
@@ -85,7 +94,7 @@ void DivePictureItem::setPixmap(const QPixmap &pix)
 void DivePictureItem::hoverEnterEvent(QGraphicsSceneHoverEvent*)
 {
 	Animations::scaleTo(this, 1.0);
-	setZValue(5);
+	setZValue(baseZValue + 5.0);
 
 	button->setOpacity(0);
 	button->show();
@@ -100,7 +109,7 @@ void DivePictureItem::setFileUrl(const QString &s)
 void DivePictureItem::hoverLeaveEvent(QGraphicsSceneHoverEvent*)
 {
 	Animations::scaleTo(this, 0.2);
-	setZValue(0);
+	setZValue(baseZValue);
 	Animations::hide(button);
 }
 
diff --git a/profile-widget/divepixmapitem.h b/profile-widget/divepixmapitem.h
index 6abe410a6..f8b922981 100644
--- a/profile-widget/divepixmapitem.h
+++ b/profile-widget/divepixmapitem.h
@@ -32,6 +32,7 @@ class DivePictureItem : public DivePixmapItem {
 public:
 	DivePictureItem(QGraphicsItem *parent = 0);
 	void setPixmap(const QPixmap& pix);
+	void setBaseZValue(double z);
 public slots:
 	void settingsChanged();
 	void removePicture();
@@ -45,6 +46,7 @@ private:
 	QGraphicsRectItem *canvas;
 	QGraphicsRectItem *shadow;
 	CloseButtonItem *button;
+	double baseZValue;
 };
 
 #endif // DIVEPIXMAPITEM_H
diff --git a/profile-widget/profilewidget2.cpp b/profile-widget/profilewidget2.cpp
index 11dddaa41..79aa2e876 100644
--- a/profile-widget/profilewidget2.cpp
+++ b/profile-widget/profilewidget2.cpp
@@ -87,6 +87,10 @@ static struct _ItemPos {
 	_Axis heartBeatWithTankBar;
 } itemPos;
 
+// Constant describing at which z-level the thumbnails are located.
+// We might add more constants here for easier customability.
+static const double thumbnailBaseZValue = 100.0;
+
 ProfileWidget2::ProfileWidget2(QWidget *parent) : QGraphicsView(parent),
 	currentState(INVALID),
 	dataModel(new DivePlotDataModel(this)),
@@ -975,6 +979,21 @@ void ProfileWidget2::fixBackgroundPos()
 	background->setY(mapToScene(y, 20).y());
 }
 
+void ProfileWidget2::scale(qreal sx, qreal sy)
+{
+	QGraphicsView::scale(sx, sy);
+
+#ifndef SUBSURFACE_MOBILE
+	// Since the zoom level changed, adjust the duration bars accordingly.
+	// We want to grow/shrink the length, but not the height and pen.
+	for (PictureEntry &p: pictures)
+		updateDurationLine(p);
+
+	// Since we created new duration lines, we have to update the order in which the thumbnails is painted.
+	updateThumbnailPaintOrder();
+#endif
+}
+
 #ifndef SUBSURFACE_MOBILE
 void ProfileWidget2::wheelEvent(QWheelEvent *event)
 {
@@ -2064,9 +2083,37 @@ void ProfileWidget2::clearPictures()
 	pictures.clear();
 }
 
+static const double unscaledDurationLineWidth = 2.5;
+static const double unscaledDurationLinePenWidth = 0.5;
+
+// Reset the duration line after an image was moved or we found a new duration
+void ProfileWidget2::updateDurationLine(PictureEntry &e)
+{
+	if (e.duration.seconds > 0) {
+		// We know the duration of this video, reset the line symbolizing its extent accordingly
+		double begin = timeAxis->posAtValue(e.offset.seconds);
+		double end = timeAxis->posAtValue(e.offset.seconds + e.duration.seconds);
+		double y = e.thumbnail->y();
+
+		// Undo scaling for pen-width and line-width. For this purpose, we use the scaling of the y-axis.
+		double scale = transform().m22();
+		double durationLineWidth = unscaledDurationLineWidth / scale;
+		double durationLinePenWidth = unscaledDurationLinePenWidth / scale;
+		e.durationLine.reset(new QGraphicsRectItem(begin, y - durationLineWidth - durationLinePenWidth, end - begin, durationLineWidth));
+		e.durationLine->setPen(QPen(getColor(GF_LINE, isGrayscale), durationLinePenWidth));
+		e.durationLine->setBrush(getColor(::BACKGROUND, isGrayscale));
+		e.durationLine->setVisible(prefs.show_pictures_in_profile);
+		scene()->addItem(e.durationLine.get());
+	} else {
+		// This is either a picture or a video with unknown duration.
+		// In case there was a line (how could that be?) remove it.
+		e.durationLine.reset();
+	}
+}
+
 // This function is called asynchronously by the thumbnailer if a thumbnail
 // was fetched from disk or freshly calculated.
-void ProfileWidget2::updateThumbnail(QString filename, QImage thumbnail)
+void ProfileWidget2::updateThumbnail(QString filename, QImage thumbnail, duration_t duration)
 {
 	// Find the picture with the given filename
 	auto it = std::find_if(pictures.begin(), pictures.end(), [&filename](const PictureEntry &e)
@@ -2078,11 +2125,20 @@ void ProfileWidget2::updateThumbnail(QString filename, QImage thumbnail)
 		// Replace the pixmap of the thumbnail with the newly calculated one.
 		int size = Thumbnailer::defaultThumbnailSize();
 		it->thumbnail->setPixmap(QPixmap::fromImage(thumbnail.scaled(size, size, Qt::KeepAspectRatio)));
+
+		// If the duration changed, update the line
+		if (duration.seconds != it->duration.seconds) {
+			it->duration = duration;
+			updateDurationLine(*it);
+			// If we created / removed a duration line, we have to update the thumbnail paint order.
+			updateThumbnailPaintOrder();
+		}
 	}
 }
 
 // Create a PictureEntry object and add its thumbnail to the scene if profile pictures are shown.
 ProfileWidget2::PictureEntry::PictureEntry(offset_t offsetIn, const QString &filenameIn, QGraphicsScene *scene) : offset(offsetIn),
+	duration(duration_t {0}),
 	filename(filenameIn),
 	thumbnail(new DivePictureItem)
 {
@@ -2101,23 +2157,37 @@ bool ProfileWidget2::PictureEntry::operator< (const PictureEntry &e) const
 	return std::tie(offset.seconds, filename) < std::tie(e.offset.seconds, e.filename);
 }
 
+// This function updates the paint order of the thumbnails and duration-lines, such that later
+// thumbnails are painted on top of previous thumbnails and duration-lines on top of the thumbnail
+// they belong to.
+void ProfileWidget2::updateThumbnailPaintOrder()
+{
+	if (!pictures.size())
+		return;
+	// To get the correct sort order, we place in thumbnails at equal z-distances
+	// between thumbnailBaseZValue and (thumbnailBaseZValue + 1.0).
+	// Duration-lines are placed between the thumbnails.
+	double z = thumbnailBaseZValue;
+	double step = 1.0 / (double)pictures.size();
+	for (PictureEntry &e: pictures) {
+		e.thumbnail->setBaseZValue(z);
+		if (e.durationLine)
+			e.durationLine->setZValue(z + step / 2.0);
+		z += step;
+	}
+}
+
 // Calculate the y-coordinates of the thumbnails, which are supposed to be sorted by x-coordinate.
 // This will also change the order in which the thumbnails are painted, to avoid weird effects,
 // when items are added later to the scene. This is done using the QGraphicsItem::packBefore() function.
 // We can't use the z-value, because that will be modified on hoverEnter and hoverExit events.
 void ProfileWidget2::calculatePictureYPositions()
 {
-	// Quit early if there are no items. The last loop in this function assumes that the vector is not empty.
-	if (pictures.empty())
-		return;
-
 	double lastX = -1.0, lastY = 0.0;
-	for (auto it = pictures.begin(); it != pictures.end(); ++it) {
-		if (!it->thumbnail)
-			continue;
+	for (PictureEntry &e: pictures) {
 		// let's put the picture at the correct time, but at a fixed "depth" on the profile
 		// not sure this is ideal, but it seems to look right.
-		double x = it->thumbnail->x();
+		double x = e.thumbnail->x();
 		double y;
 		if (lastX >= 0.0 && fabs(x - lastX) < 3 && lastY <= (10 + 14 * 3))
 			y = lastY + 3;
@@ -2125,18 +2195,10 @@ void ProfileWidget2::calculatePictureYPositions()
 			y = 10;
 		lastX = x;
 		lastY = y;
-		it->thumbnail->setY(y);
-
-		// hoverEnter and hoverExit events modify the z-value. Objects with different z-values
-		// are not considered in stackBefore() calls. Therefore, just to be sure, reset the
-		// z-values of all picture entries.
-		it->thumbnail->setZValue(0.0);
+		e.thumbnail->setY(y);
+		updateDurationLine(e); // If we changed the y-position, we also have to change the duration-line.
 	}
-
-	// Plot the items in the correct order. Experience showed that this works only
-	// if we rearrange the items starting from the back. Therefore, use rbegin() and rend().
-	for (auto it = pictures.rbegin(); std::next(it) != pictures.rend(); ++it)
-		std::next(it)->thumbnail->stackBefore(it->thumbnail.get());
+	updateThumbnailPaintOrder();
 }
 
 void ProfileWidget2::updateThumbnailXPos(PictureEntry &e)
diff --git a/profile-widget/profilewidget2.h b/profile-widget/profilewidget2.h
index 2640fb85a..bbad5b7cc 100644
--- a/profile-widget/profilewidget2.h
+++ b/profile-widget/profilewidget2.h
@@ -74,6 +74,7 @@ public:
 
 	ProfileWidget2(QWidget *parent = 0);
 	void resetZoom();
+	void scale(qreal sx, qreal sy);
 	void plotDive(struct dive *d = 0, bool force = false, bool clearPictures = false);
 	void setupItem(AbstractProfilePolygonItem *item, DiveCartesianAxis *vAxis, int vData, int hData, int zValue);
 	void setPrintMode(bool mode, bool grayscale = false);
@@ -127,7 +128,7 @@ slots: // Necessary to call from QAction's signals.
 	void deleteCurrentDC();
 	void pointInserted(const QModelIndex &parent, int start, int end);
 	void pointsRemoved(const QModelIndex &, int start, int end);
-	void updateThumbnail(QString filename, QImage thumbnail);
+	void updateThumbnail(QString filename, QImage thumbnail, duration_t duration);
 
 	/* this is called for every move on the handlers. maybe we can speed up this a bit? */
 	void recreatePlannedDive();
@@ -234,14 +235,19 @@ private:
 	// Pictures that are outside of the dive time are not shown.
 	struct PictureEntry {
 		offset_t offset;
+		duration_t duration;
 		QString filename;
 		std::unique_ptr<DivePictureItem> thumbnail;
+		// For videos with known duration, we represent the duration of the video by a line
+		std::unique_ptr<QGraphicsRectItem> durationLine;
 		PictureEntry (offset_t offsetIn, const QString &filenameIn, QGraphicsScene *scene);
 		bool operator< (const PictureEntry &e) const;
 	};
 	void updateThumbnailXPos(PictureEntry &e);
 	std::vector<PictureEntry> pictures;
 	void calculatePictureYPositions();
+	void updateDurationLine(PictureEntry &e);
+	void updateThumbnailPaintOrder();
 
 	QList<DiveHandler *> handles;
 	void repositionDiveHandlers();