diff --git a/src/tools/circlecount/circlecounttool.cpp b/src/tools/circlecount/circlecounttool.cpp index 3b9ca65c..9a53a994 100644 --- a/src/tools/circlecount/circlecounttool.cpp +++ b/src/tools/circlecount/circlecounttool.cpp @@ -89,8 +89,11 @@ void CircleCountTool::process(QPainter& painter, textRect, Qt::AlignCenter, QString::number(m_count)); } - // Lightness value ranges from 0-255, we split at 75 as this looks best - if (m_color.lightness() <= 75) { + // Calculate the perceptive luminance - human eye favors green color + double luma = ((0.299 * m_color.red()) + (0.587 * m_color.green()) + + (0.114 * m_color.blue())) / + 255; + if (luma <= 0.5) { painter.setPen(Qt::white); } else { painter.setPen(Qt::black);