MaskablePixmapWidget: auto-detect a suitable background color

widget/friendwidget.cpp

@@ -202,6 +202,7 @@ void FriendWidget::onAvatarChange(int FriendId, const QPixmap& pic)
 
     isDefaultAvatar = false;
     avatar->setPixmap(pic);
+    avatar->autopickBackground();
 }
 
 void FriendWidget::onAvatarRemoved(int FriendId)

widget/groupwidget.cpp

@@ -39,8 +39,8 @@ GroupWidget::GroupWidget(int GroupId, QString Name)
     textLayout.setMargin(0);
     setLayoutDirection(Qt::LeftToRight); // parent might have set Qt::RightToLeft
 
-    avatar = new MaskablePixmapWidget(this, QSize(40,40), QString(), Qt::transparent);
+    avatar = new MaskablePixmapWidget(this, QSize(40,40), ":/img/avatar_mask.png");
-    avatar->setPixmap(QPixmap(":img/group.png"));
+    avatar->setPixmap(QPixmap(":img/group_dark.png"));
     statusPic.setPixmap(QPixmap(":img/status/dot_online.png"));
     name.setText(Name);
     QFont small;
@@ -139,7 +139,7 @@ void GroupWidget::setAsInactiveChatroom()
     QPalette pal3;
     pal3.setColor(QPalette::Background, QColor(65,65,65,255));
     this->setPalette(pal3);
-    avatar->setPixmap(QPixmap(":img/group.png"));
+    avatar->setPixmap(QPixmap(":img/group_dark.png"));
 }
 
 void GroupWidget::updateStatusLight()

widget/maskablepixmapwidget.cpp

@@ -17,10 +17,11 @@
 #include "maskablepixmapwidget.h"
 #include <QPainter>
 
-MaskablePixmapWidget::MaskablePixmapWidget(QWidget *parent, QSize size, QString maskName, QColor background)
+MaskablePixmapWidget::MaskablePixmapWidget(QWidget *parent, QSize size, QString maskName, bool autopickBackground)
     : QWidget(parent)
-    , backgroundColor(background)
+    , backgroundColor(Qt::white)
     , clickable(false)
+    , autoBackground(autopickBackground)
 {
     setFixedSize(size);
 
@@ -30,6 +31,47 @@ MaskablePixmapWidget::MaskablePixmapWidget(QWidget *parent, QSize size, QString
         mask = QPixmap(maskName).scaled(size, Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
 }
 
+void MaskablePixmapWidget::autopickBackground()
+{
+    QImage pic = pixmap.toImage();
+
+    if (pic.isNull())
+        return;
+
+    qreal r = 0.0f;
+    qreal g = 0.0f;
+    qreal b = 0.0f;
+    float weight = 1.0f;
+
+    for (int x=0;x<pic.width();++x)
+    {
+        for (int y=0;y<pic.height();++y)
+        {
+            QRgb color = pic.pixel(x,y);
+            r += qRed(color) / 255.0f;
+            g += qGreen(color) / 255.0f;
+            b += qBlue(color) / 255.0f;
+
+            weight += qAlpha(color) / 255.0f;
+        }
+    }
+
+    r /= weight;
+    g /= weight;
+    b /= weight;
+
+    QColor color = QColor::fromRgbF(r,g,b);
+    backgroundColor =  QColor::fromRgb(0xFFFFFF ^ color.rgb());
+
+    update();
+}
+
+void MaskablePixmapWidget::setBackground(QColor color)
+{
+    backgroundColor = color;
+    update();
+}
+
 void MaskablePixmapWidget::setClickable(bool clickable)
 {
     this->clickable = clickable;
@@ -42,8 +84,15 @@ void MaskablePixmapWidget::setClickable(bool clickable)
 
 void MaskablePixmapWidget::setPixmap(const QPixmap &pmap)
 {
-    pixmap = pmap.scaled(width(), height(), Qt::KeepAspectRatioByExpanding, Qt::SmoothTransformation);
+    if (!pmap.isNull())
-    update();
+    {
+        pixmap = pmap.scaled(width(), height(), Qt::KeepAspectRatioByExpanding, Qt::SmoothTransformation);
+
+        if (autoBackground)
+            autopickBackground();
+
+        update();
+    }
 }
 
 QPixmap MaskablePixmapWidget::getPixmap() const

widget/maskablepixmapwidget.h

@@ -23,8 +23,10 @@ class MaskablePixmapWidget : public QWidget
 {
     Q_OBJECT
 public:
-    MaskablePixmapWidget(QWidget *parent, QSize size, QString maskName, QColor background = Qt::white);
+    MaskablePixmapWidget(QWidget *parent, QSize size, QString maskName = QString(), bool autopickBackground = true);
 
+    void autopickBackground();
+    void setBackground(QColor color);
     void setClickable(bool clickable);
     void setPixmap(const QPixmap &pmap);
     QPixmap getPixmap() const;
@@ -43,6 +45,7 @@ private:
     QString maskName;
     QColor backgroundColor;
     bool clickable;
+    bool autoBackground;
 };
 
 #endif // MASKABLEPIXMAPWIDGET_H