Viewport: Implemented on-canvas drag

[pulseview.git] / pv / view / viewport.cpp

diff --git a/pv/view/viewport.cpp b/pv/view/viewport.cpp
index 0e89f3ad96fc6b983d3ed1d9d8fe2cb495e59f2b..2772c7764ead3a45b2c76733be6b0fe98d252c05 100644 (file)
--- a/pv/view/viewport.cpp
+++ b/pv/view/viewport.cpp
@@ -21,6 +21,7 @@
 #include <cassert>
 #include <cmath>
 #include <algorithm>
+#include <limits>
 
 #include "signal.hpp"
 #include "view.hpp"
@@ -37,6 +38,7 @@ using std::copy;
 using std::max;
 using std::min;
 using std::none_of;
+using std::numeric_limits;
 using std::shared_ptr;
 using std::stable_sort;
 using std::vector;
@@ -46,7 +48,7 @@ namespace view {
 
 Viewport::Viewport(View &parent) :
        ViewWidget(parent),
-       mouse_down_valid_(false),
+       drag_offset_(numeric_limits<double>::signaling_NaN()),
        pinch_zoom_active_(false)
 {
        setAutoFillBackground(true);
@@ -63,6 +65,25 @@ shared_ptr<ViewItem> Viewport::get_mouse_over_item(const QPoint &pt)
        return nullptr;
 }
 
+void Viewport::drag()
+{
+       drag_offset_ = view_.offset();
+}
+
+void Viewport::drag_by(const QPoint &delta)
+{
+       if (isnan(drag_offset_))
+               return;
+
+       view_.set_scale_offset(view_.scale(), drag_offset_ -
+               delta.x() * view_.scale());
+}
+
+void Viewport::drag_release()
+{
+       drag_offset_ = numeric_limits<double>::signaling_NaN();
+}
+
 vector< shared_ptr<ViewItem> > Viewport::items()
 {
        vector< shared_ptr<ViewItem> > items(view_.begin(), view_.end());
@@ -104,13 +125,12 @@ bool Viewport::touch_event(QTouchEvent *event)
 
                if (touchPoint0.state() & Qt::TouchPointReleased) {
                        // Primary touch released
-                       mouse_down_valid_ = false;
+                       drag_release();
                } else {
                        // Update the mouse down fields so that continued
                        // dragging with the primary touch will work correctly
                        mouse_down_point_ = touchPoint0.pos().toPoint();
-                       mouse_down_offset_ = view_.offset();
-                       mouse_down_valid_ = true;
+                       drag();
                }
        }
 
@@ -154,43 +174,6 @@ void Viewport::paintEvent(QPaintEvent*)
        p.end();
 }
 
-void Viewport::mousePressEvent(QMouseEvent *event)
-{
-       assert(event);
-
-       if (event->button() == Qt::LeftButton) {
-               mouse_down_point_ = event->pos();
-               mouse_down_offset_ = view_.offset();
-               mouse_down_valid_ = true;
-       }
-}
-
-void Viewport::mouseReleaseEvent(QMouseEvent *event)
-{
-       assert(event);
-
-       if (event->button() == Qt::LeftButton)
-               mouse_down_valid_ = false;
-}
-
-void Viewport::mouseMoveEvent(QMouseEvent *event)
-{
-       assert(event);
-
-       if (event->buttons() & Qt::LeftButton) {
-               if (!mouse_down_valid_) {
-                       mouse_down_point_ = event->pos();
-                       mouse_down_offset_ = view_.offset();
-                       mouse_down_valid_ = true;
-               }
-
-               view_.set_scale_offset(view_.scale(),
-                       mouse_down_offset_ +
-                       (mouse_down_point_ - event->pos()).x() *
-                       view_.scale());
-       }
-}
-
 void Viewport::mouseDoubleClickEvent(QMouseEvent *event)
 {
        assert(event);