Custom LineLabel widget to display line preview

scwx-qt/scwx-qt.cmake

@@ -252,6 +252,7 @@ set(HDR_UI source/scwx/qt/ui/about_dialog.hpp
            source/scwx/qt/ui/level2_products_widget.hpp
            source/scwx/qt/ui/level2_settings_widget.hpp
            source/scwx/qt/ui/level3_products_widget.hpp
+           source/scwx/qt/ui/line_label.hpp
            source/scwx/qt/ui/open_url_dialog.hpp
            source/scwx/qt/ui/placefile_dialog.hpp
            source/scwx/qt/ui/placefile_settings_widget.hpp
@@ -278,6 +279,7 @@ set(SRC_UI source/scwx/qt/ui/about_dialog.cpp
            source/scwx/qt/ui/level2_products_widget.cpp
            source/scwx/qt/ui/level2_settings_widget.cpp
            source/scwx/qt/ui/level3_products_widget.cpp
+           source/scwx/qt/ui/line_label.cpp
            source/scwx/qt/ui/open_url_dialog.cpp
            source/scwx/qt/ui/placefile_dialog.cpp
            source/scwx/qt/ui/placefile_settings_widget.cpp

scwx-qt/source/scwx/qt/ui/line_label.cpp

@@ -0,0 +1,176 @@
+#include <scwx/qt/ui/line_label.hpp>
+#include <scwx/util/logger.hpp>
+
+#include <QEvent>
+#include <QPainter>
+
+namespace scwx
+{
+namespace qt
+{
+namespace ui
+{
+
+static const std::string logPrefix_ = "scwx::qt::ui::line_label";
+static const auto        logger_    = scwx::util::Logger::Create(logPrefix_);
+
+class LineLabel::Impl
+{
+public:
+   explicit Impl() {};
+   ~Impl() = default;
+
+   QImage GenerateImage() const;
+
+   std::size_t borderWidth_ {1};
+   std::size_t highlightWidth_ {1};
+   std::size_t lineWidth_ {3};
+
+   boost::gil::rgba8_pixel_t borderColor_ {0, 0, 0, 255};
+   boost::gil::rgba8_pixel_t highlightColor_ {255, 255, 0, 255};
+   boost::gil::rgba8_pixel_t lineColor_ {0, 0, 255, 255};
+
+   QPixmap pixmap_ {};
+   bool    pixmapDirty_ {true};
+};
+
+LineLabel::LineLabel(QWidget* parent) :
+    QFrame(parent), p {std::make_unique<Impl>()}
+{
+}
+
+LineLabel::~LineLabel() {}
+
+void LineLabel::set_border_width(std::size_t width)
+{
+   p->borderWidth_ = width;
+   p->pixmapDirty_ = true;
+   update();
+}
+
+void LineLabel::set_highlight_width(std::size_t width)
+{
+   p->highlightWidth_ = width;
+   p->pixmapDirty_    = true;
+   update();
+}
+
+void LineLabel::set_line_width(std::size_t width)
+{
+   p->lineWidth_   = width;
+   p->pixmapDirty_ = true;
+   update();
+}
+
+void LineLabel::set_border_color(boost::gil::rgba8_pixel_t color)
+{
+   p->borderColor_ = color;
+   p->pixmapDirty_ = true;
+   update();
+}
+
+void LineLabel::set_highlight_color(boost::gil::rgba8_pixel_t color)
+{
+   p->highlightColor_ = color;
+   p->pixmapDirty_    = true;
+   update();
+}
+
+void LineLabel::set_line_color(boost::gil::rgba8_pixel_t color)
+{
+   p->lineColor_   = color;
+   p->pixmapDirty_ = true;
+   update();
+}
+
+QSize LineLabel::minimumSizeHint() const
+{
+   return sizeHint();
+}
+
+QSize LineLabel::sizeHint() const
+{
+   QMargins margins = contentsMargins();
+
+   const std::size_t width = 1;
+   const std::size_t height =
+      (p->borderWidth_ + p->highlightWidth_) * 2 + p->lineWidth_;
+
+   return QSize(static_cast<int>(width) + margins.left() + margins.right(),
+                static_cast<int>(height) + margins.top() + margins.bottom());
+}
+
+void LineLabel::paintEvent(QPaintEvent* e)
+{
+   logger_->trace("paintEvent");
+
+   QFrame::paintEvent(e);
+
+   if (p->pixmapDirty_)
+   {
+      QImage image    = p->GenerateImage();
+      p->pixmap_      = QPixmap::fromImage(image);
+      p->pixmapDirty_ = false;
+   }
+
+   // Don't stretch the line pixmap vertically
+   QRect rect = contentsRect();
+   if (rect.height() > p->pixmap_.height())
+   {
+      int dy  = rect.height() - p->pixmap_.height();
+      int dy1 = dy / 2;
+      int dy2 = dy - dy1;
+      rect.adjust(0, dy1, 0, -dy2);
+   }
+
+   QPainter painter(this);
+   painter.drawPixmap(rect, p->pixmap_);
+}
+
+QImage LineLabel::Impl::GenerateImage() const
+{
+   const QRgb borderRgba    = qRgba(static_cast<int>(borderColor_[0]),
+                                 static_cast<int>(borderColor_[1]),
+                                 static_cast<int>(borderColor_[2]),
+                                 static_cast<int>(borderColor_[3]));
+   const QRgb highlightRgba = qRgba(static_cast<int>(highlightColor_[0]),
+                                    static_cast<int>(highlightColor_[1]),
+                                    static_cast<int>(highlightColor_[2]),
+                                    static_cast<int>(highlightColor_[3]));
+   const QRgb lineRgba      = qRgba(static_cast<int>(lineColor_[0]),
+                               static_cast<int>(lineColor_[1]),
+                               static_cast<int>(lineColor_[2]),
+                               static_cast<int>(lineColor_[3]));
+
+   const std::size_t width  = 1;
+   const std::size_t height = (borderWidth_ + highlightWidth_) * 2 + lineWidth_;
+
+   QImage image(static_cast<int>(width),
+                static_cast<int>(height),
+                QImage::Format::Format_ARGB32);
+
+   std::size_t y = 0;
+   for (std::size_t i = 0; i < borderWidth_; ++i, ++y)
+   {
+      image.setPixel(0, static_cast<int>(y), borderRgba);
+      image.setPixel(0, static_cast<int>(height - 1 - y), borderRgba);
+   }
+
+   for (std::size_t i = 0; i < highlightWidth_; ++i, ++y)
+   {
+      image.setPixel(0, static_cast<int>(y), highlightRgba);
+      image.setPixel(0, static_cast<int>(height - 1 - y), highlightRgba);
+   }
+
+   for (std::size_t i = 0; i < lineWidth_; ++i, ++y)
+   {
+      image.setPixel(0, static_cast<int>(y), lineRgba);
+      image.setPixel(0, static_cast<int>(height - 1 - y), lineRgba);
+   }
+
+   return image;
+}
+
+} // namespace ui
+} // namespace qt
+} // namespace scwx

scwx-qt/source/scwx/qt/ui/line_label.hpp

@@ -0,0 +1,43 @@
+#pragma once
+
+#include <QFrame>
+
+#include <boost/gil/typedefs.hpp>
+
+namespace scwx
+{
+namespace qt
+{
+namespace ui
+{
+
+class LineLabel : public QFrame
+{
+   Q_OBJECT
+   Q_DISABLE_COPY_MOVE(LineLabel)
+
+public:
+   explicit LineLabel(QWidget* parent = nullptr);
+   ~LineLabel();
+
+   void set_border_color(boost::gil::rgba8_pixel_t color);
+   void set_highlight_color(boost::gil::rgba8_pixel_t color);
+   void set_line_color(boost::gil::rgba8_pixel_t color);
+
+   void set_border_width(std::size_t width);
+   void set_highlight_width(std::size_t width);
+   void set_line_width(std::size_t width);
+
+protected:
+   QSize minimumSizeHint() const override;
+   QSize sizeHint() const override;
+   void  paintEvent(QPaintEvent* e) override;
+
+private:
+   class Impl;
+   std::unique_ptr<Impl> p;
+};
+
+} // namespace ui
+} // namespace qt
+} // namespace scwx