Update track zooming to minimize redrawing updates

Author: kmichaelfox

Source/Plugins/LfpDisplayNodeAlpha/LfpDisplayCanvas.cpp

@@ -1324,7 +1324,7 @@ void LfpDisplayOptions::setRangeSelection(float range, bool canvasMustUpdate)
 
 }
 
-void LfpDisplayOptions::setSpreadSelection(int spread, bool canvasMustUpdate)
+void LfpDisplayOptions::setSpreadSelection(int spread, bool canvasMustUpdate, bool deferDisplayRefresh)
 {
 
     if (canvasMustUpdate)
@@ -1337,8 +1337,11 @@ void LfpDisplayOptions::setSpreadSelection(int spread, bool canvasMustUpdate)
         selectedSpread = spreadSelection->getSelectedId();
         selectedSpreadValue = spreadSelection->getText();
 
-        canvas->repaint();
-        canvas->refresh();
+        if (!deferDisplayRefresh)
+        {
+            canvas->repaint();
+            canvas->refresh();
+        }
     }
 }
 
@@ -3573,6 +3576,7 @@ void LfpChannelDisplayInfo::mouseDrag(const MouseEvent &e)
     {
         if (e.mods.isCommandDown() && !display->getSingleChannelState())  // CTRL + drag -> change channel spacing
         {
+            
             // init state in our track zooming info struct
             if (!display->trackZoomInfo.isScrollingY)
             {
@@ -3615,19 +3619,24 @@ void LfpChannelDisplayInfo::mouseDrag(const MouseEvent &e)
             }
 
             // set channel heights for all channel
-            display->setChannelHeight(newHeight);
-            display->setBounds(0,0,display->getWidth()-0, display->getChannelHeight()*display->drawableChannels.size()); // update height so that the scrollbar is correct
+//            display->setChannelHeight(newHeight);
+            for (int i = 0; i < display->getNumChannels(); ++i)
+            {
+                display->channels[i]->setChannelHeight(newHeight);
+                display->channelInfo[i]->setChannelHeight(newHeight);
+            }
+            
+            options->setSpreadSelection(newHeight, false, true); // update combobox
 
-            canvas->viewport->setViewPositionProportionately(display->trackZoomInfo.zoomPivotRatioX, display->trackZoomInfo.zoomPivotRatioY);
+            canvas->fullredraw = true;//issue full redraw - scrolling without modifier doesnt require a full redraw
+            
+            display->setBounds(0,0,display->getWidth()-0, display->getChannelHeight()*display->drawableChannels.size()); // update height so that the scrollbar is correct
 
             int newViewportY = display->trackZoomInfo.zoomPivotRatioY * display->getHeight() - display->trackZoomInfo.zoomPivotViewportOffset.getY();
             if (newViewportY < 0) newViewportY = 0; // make sure we don't adjust beyond the edge of the actual view
 
-            canvas->viewport->setViewPosition(display->trackZoomInfo.zoomPivotRatioX, newViewportY);
-            
-            options->setSpreadSelection(newHeight); // update combobox
+            canvas->viewport->setViewPosition(0, newViewportY);
 
-            canvas->fullredraw = true;//issue full redraw - scrolling without modifier doesnt require a full redraw
         }
     }
 }

Source/Plugins/LfpDisplayNodeAlpha/LfpDisplayCanvas.h

@@ -251,7 +251,7 @@ class LfpDisplayOptions : public Component,
     void resized();
 
     void setRangeSelection(float range, bool canvasMustUpdate = false); // set range selection combo box to correct value if it has been changed by scolling etc.
-    void setSpreadSelection(int spread, bool canvasMustUpdate = false); // set spread selection combo box to correct value if it has been changed by scolling etc.
+    void setSpreadSelection(int spread, bool canvasMustUpdate = false, bool deferDisplayRefresh = false); // set spread selection combo box to correct value if it has been changed by scolling etc.
 
     void comboBoxChanged(ComboBox* cb);
     void buttonClicked(Button* button);