Cache signal label text size at draw time for later use

[pulseview.git] / pv / signal.cpp

diff --git a/pv/signal.cpp b/pv/signal.cpp
index 7d3dd66362f4c5ab182b4503ab2e0294d5f93066..091dd8d4406ef62dfc56b325c96f770890342323 100644 (file)
--- a/pv/signal.cpp
+++ b/pv/signal.cpp
@@ -43,7 +43,9 @@ void Signal::paint_label(QPainter &p, const QRect &rect, bool hover)
 
        const QColor colour = get_colour();
        const float nominal_offset = get_nominal_offset(rect);
 
        const QColor colour = get_colour();
        const float nominal_offset = get_nominal_offset(rect);

-       const QRectF label_rect = get_label_rect(p, rect);
+
+       compute_text_size(p);
+       const QRectF label_rect = get_label_rect(rect);

 
        // Paint the label
        const QPointF points[] = {
 
        // Paint the label
        const QPointF points[] = {


@@ -79,10 +81,9 @@ void Signal::paint_label(QPainter &p, const QRect &rect, bool hover)
        p.drawText(label_rect, Qt::AlignCenter | Qt::AlignVCenter, _name);
 }
 
        p.drawText(label_rect, Qt::AlignCenter | Qt::AlignVCenter, _name);
 }
 

-bool Signal::pt_in_label_rect(QPainter &p,
-       const QRect &rect, const QPoint &point)
+bool Signal::pt_in_label_rect(const QRect &rect, const QPoint &point)

 {
 {

-       const QRectF label = get_label_rect(p, rect);
+       const QRectF label = get_label_rect(rect);

        return QRectF(
                QPointF(label.left() - LabelHitPadding,
                        label.top() - LabelHitPadding),
        return QRectF(
                QPointF(label.left() - LabelHitPadding,
                        label.top() - LabelHitPadding),


@@ -91,15 +92,17 @@ bool Signal::pt_in_label_rect(QPainter &p,
                ).contains(point);
 }
 
                ).contains(point);
 }
 

-QRectF Signal::get_label_rect(QPainter &p, const QRect &rect)
+void Signal::compute_text_size(QPainter &p)

 {
 {

-       const QSizeF text_size = p.boundingRect(
-               QRectF(0, 0, rect.width(), 0), 0, _name).size();
+       _text_size = p.boundingRect(QRectF(), 0, _name).size();
+}

 
 

+QRectF Signal::get_label_rect(const QRect &rect)
+{

        const float nominal_offset = get_nominal_offset(rect);
        const QSizeF label_size(
        const float nominal_offset = get_nominal_offset(rect);
        const QSizeF label_size(

-               text_size.width() + LabelPadding.width() * 2,
-               text_size.height() + LabelPadding.height() * 2);
+               _text_size.width() + LabelPadding.width() * 2,
+               _text_size.height() + LabelPadding.height() * 2);

        const float label_arrow_length = label_size.height() / 2;
        return QRectF(
                rect.right() - label_arrow_length - label_size.width(),
        const float label_arrow_length = label_size.height() / 2;
        return QRectF(
                rect.right() - label_arrow_length - label_size.width(),