qcam: New viewfinder hierarchy

Create ViewFinder base class and rename the original ViewFinder
as QPainter-based ViewFinder.

Signed-off-by: Show Liu <show.liu@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 181 insertions, 0 deletions

diff --git a/src/qcam/viewfinder_qt.cpp b/src/qcam/viewfinder_qt.cpp
new file mode 100644
index 00000000..e436714c
--- /dev/null
+++ b/src/qcam/viewfinder_qt.cpp
@@ -0,0 +1,181 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * viewfinder_qt.cpp - qcam - QPainter-based ViewFinder
+ */
+
+#include "viewfinder_qt.h"
+
+#include <stdint.h>
+#include <utility>
+
+#include <QImage>
+#include <QImageWriter>
+#include <QMap>
+#include <QMutexLocker>
+#include <QPainter>
+#include <QtDebug>
+
+#include <libcamera/formats.h>
+
+#include "format_converter.h"
+
+static const QMap<libcamera::PixelFormat, QImage::Format> nativeFormats
+{
+#if QT_VERSION >= QT_VERSION_CHECK(5, 2, 0)
+	{ libcamera::formats::ABGR8888, QImage::Format_RGBA8888 },
+#endif
+	{ libcamera::formats::ARGB8888, QImage::Format_RGB32 },
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+	{ libcamera::formats::RGB888, QImage::Format_BGR888 },
+#endif
+	{ libcamera::formats::BGR888, QImage::Format_RGB888 },
+};
+
+ViewFinderQt::ViewFinderQt(QWidget *parent)
+	: QWidget(parent), buffer_(nullptr)
+{
+	icon_ = QIcon(":camera-off.svg");
+}
+
+ViewFinderQt::~ViewFinderQt()
+{
+}
+
+const QList<libcamera::PixelFormat> &ViewFinderQt::nativeFormats() const
+{
+	static const QList<libcamera::PixelFormat> formats = ::nativeFormats.keys();
+	return formats;
+}
+
+int ViewFinderQt::setFormat(const libcamera::PixelFormat &format,
+			    const QSize &size)
+{
+	image_ = QImage();
+
+	/*
+	 * If format conversion is needed, configure the converter and allocate
+	 * the destination image.
+	 */
+	if (!::nativeFormats.contains(format)) {
+		int ret = converter_.configure(format, size);
+		if (ret < 0)
+			return ret;
+
+		image_ = QImage(size, QImage::Format_RGB32);
+
+		qInfo() << "Using software format conversion from"
+			<< format.toString().c_str();
+	} else {
+		qInfo() << "Zero-copy enabled";
+	}
+
+	format_ = format;
+	size_ = size;
+
+	updateGeometry();
+	return 0;
+}
+
+void ViewFinderQt::render(libcamera::FrameBuffer *buffer, MappedBuffer *map)
+{
+	if (buffer->planes().size() != 1) {
+		qWarning() << "Multi-planar buffers are not supported";
+		return;
+	}
+
+	unsigned char *memory = static_cast<unsigned char *>(map->memory);
+	size_t size = buffer->metadata().planes[0].bytesused;
+
+	{
+		QMutexLocker locker(&mutex_);
+
+		if (::nativeFormats.contains(format_)) {
+			/*
+			 * If the frame format is identical to the display
+			 * format, create a QImage that references the frame
+			 * and store a reference to the frame buffer. The
+			 * previously stored frame buffer, if any, will be
+			 * released.
+			 *
+			 * \todo Get the stride from the buffer instead of
+			 * computing it naively
+			 */
+			image_ = QImage(memory, size_.width(), size_.height(),
+					size / size_.height(),
+					::nativeFormats[format_]);
+			std::swap(buffer, buffer_);
+		} else {
+			/*
+			 * Otherwise, convert the format and release the frame
+			 * buffer immediately.
+			 */
+			converter_.convert(memory, size, &image_);
+		}
+	}
+
+	update();
+
+	if (buffer)
+		renderComplete(buffer);
+}
+
+void ViewFinderQt::stop()
+{
+	image_ = QImage();
+
+	if (buffer_) {
+		renderComplete(buffer_);
+		buffer_ = nullptr;
+	}
+
+	update();
+}
+
+QImage ViewFinderQt::getCurrentImage()
+{
+	QMutexLocker locker(&mutex_);
+
+	return image_.copy();
+}
+
+void ViewFinderQt::paintEvent(QPaintEvent *)
+{
+	QPainter painter(this);
+
+	/* If we have an image, draw it. */
+	if (!image_.isNull()) {
+		painter.drawImage(rect(), image_, image_.rect());
+		return;
+	}
+
+	/*
+	 * Otherwise, draw the camera stopped icon. Render it to the pixmap if
+	 * the size has changed.
+	 */
+	constexpr int margin = 20;
+
+	if (vfSize_ != size() || pixmap_.isNull()) {
+		QSize vfSize = size() - QSize{ 2 * margin, 2 * margin };
+		QSize pixmapSize{ 1, 1 };
+		pixmapSize.scale(vfSize, Qt::KeepAspectRatio);
+		pixmap_ = icon_.pixmap(pixmapSize);
+
+		vfSize_ = size();
+	}
+
+	QPoint point{ margin, margin };
+	if (pixmap_.width() < width() - 2 * margin)
+		point.setX((width() - pixmap_.width()) / 2);
+	else
+		point.setY((height() - pixmap_.height()) / 2);
+
+	painter.setBackgroundMode(Qt::OpaqueMode);
+	painter.drawPixmap(point, pixmap_);
+}
+
+QSize ViewFinderQt::sizeHint() const
+{
+	return size_.isValid() ? size_ : QSize(640, 480);
+}