Implement "always zoom to fit" feature

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

diff --git a/pv/view/view.cpp b/pv/view/view.cpp
index 130d2d788cfaf862cbb2c83b03fbac8e48f7e4a0..d4aa161959ab2bc7829d05dad08b0c0c293b4e75 100644 (file)
--- a/pv/view/view.cpp
+++ b/pv/view/view.cpp
@@ -86,7 +86,7 @@ const double View::MaxScale = 1e9;
 const double View::MinScale = 1e-15;
 
 const int View::MaxScrollValue = INT_MAX / 2;
-const int View::MaxViewAutoUpdateRate = 25; // No more than 25 Hz
+const int View::MaxViewAutoUpdateRate = 25; // No more than 25 Hz with sticky scrolling
 
 const int View::ScaleUnits[3] = {1, 2, 5};
 
@@ -100,6 +100,7 @@ View::View(Session &session, QWidget *parent) :
        offset_(0),
        updating_scroll_(false),
        sticky_scrolling_(false), // Default setting is set in MainWindow::setup_ui()
+       always_zoom_to_fit_(false),
        tick_period_(0.0),
        tick_prefix_(0),
        show_cursors_(false),
@@ -248,8 +249,17 @@ void View::zoom(double steps, int offset)
        set_zoom(scale_ * pow(3.0/2.0, -steps), offset);
 }
 
-void View::zoom_fit()
+void View::zoom_fit(bool gui_state)
 {
+       // Act as one-shot when stopped, toggle along with the GUI otherwise
+       if (session_.get_capture_state() == Session::Stopped) {
+               always_zoom_to_fit_ = false;
+               always_zoom_to_fit_changed(false);
+       } else {
+               always_zoom_to_fit_ = gui_state;
+               always_zoom_to_fit_changed(gui_state);
+       }
+
        const pair<double, double> extents = get_time_extents();
        const double delta = extents.second - extents.first;
        if (delta < 1e-12)
@@ -295,11 +305,20 @@ void View::zoom_one_to_one()
 
 void View::set_scale_offset(double scale, double offset)
 {
-       // Disable sticky scrolling when acquisition runs and user drags the viewport
+       // Disable sticky scrolling / always zoom to fit when acquisition runs
+       // and user drags the viewport
        if ((scale_ == scale) && (offset_ != offset) &&
-                       sticky_scrolling_ && (session_.get_capture_state() == Session::Running)) {
-               sticky_scrolling_ = false;
-               sticky_scrolling_changed(false);
+                       (session_.get_capture_state() == Session::Running)) {
+
+               if (sticky_scrolling_) {
+                       sticky_scrolling_ = false;
+                       sticky_scrolling_changed(false);
+               }
+
+               if (always_zoom_to_fit_) {
+                       always_zoom_to_fit_ = false;
+                       always_zoom_to_fit_changed(false);
+               }
        }
 
        scale_ = scale;
@@ -449,6 +468,10 @@ void View::get_scroll_layout(double &length, double &offset) const
 
 void View::set_zoom(double scale, int offset)
 {
+       // Reset the "always zoom to fit" feature as the user changed the zoom
+       always_zoom_to_fit_ = false;
+       always_zoom_to_fit_changed(false);
+
        const double cursor_offset = offset_ + scale_ * offset;
        const double new_scale = max(min(scale, MaxScale), MinScale);
        const double new_offset = cursor_offset - new_scale * offset;
@@ -847,7 +870,13 @@ void View::signals_changed()
 
 void View::data_updated()
 {
-       if (sticky_scrolling_) {
+       // Reset "always zoom to fit" when we change to the stopped state
+       if (always_zoom_to_fit_ && (session_.get_capture_state() == Session::Stopped)) {
+               always_zoom_to_fit_ = false;
+               always_zoom_to_fit_changed(false);
+       }
+
+       if (always_zoom_to_fit_ || sticky_scrolling_) {
                if (!delayed_view_updater_.isActive())
                        delayed_view_updater_.start();
        } else {
@@ -859,6 +888,9 @@ void View::data_updated()
 
 void View::perform_delayed_view_update()
 {
+       if (always_zoom_to_fit_)
+               zoom_fit(true);
+
        if (sticky_scrolling_) {
                // Make right side of the view sticky
                double length = 0, offset;