Debug and improve focus and scrollbars code

src/CGEditor.cpp

@@ -8,6 +8,7 @@ CGEditor::CGEditor() {
   MT = new MoveTable(&status);
   MA = new Margin(&status);
   ME = new Menu(&status);
+  TF=nullptr;
   // Default Standard NagTable: https://en.wikipedia.org/wiki/Numeric_Annotation_Glyphs
   status.NagTable[0]="";
   status.NagTable[1]="!";
@@ -81,6 +82,14 @@ void CGEditor::Draw() {
   MA->Refresh();
   MT->Refresh();
   MA->DrawMargin(MT->GetVariationsMarging());
+  // Check if we need to focus on a specific move:
+  if(TF!=nullptr){
+    double X,Y;
+    MT->GetMoveXY(TF,X,Y);
+    SBH->Focus(X+status.MoveWidth);
+    SBV->Focus(Y+status.MoveHeight);
+    TF=nullptr;
+  }
   SBV->Refresh();
   SBH->Refresh();
   ME->Refresh();
@@ -181,9 +190,6 @@ std::uint8_t CGEditor::GetNAGId(const std::string& symbol) const{
 }
 
 void CGEditor::FocusOnMove(CMI::HalfMove* move){
-  double X,Y;
-  MT->GetMoveXY(move,X,Y);
-  SBH->Focus(X+status.MoveWidth);
-  SBV->Focus(Y+status.MoveHeight);
+  TF=move;
 }
 } // namespace cgeditor

src/CGEditor.hpp

@@ -19,6 +19,8 @@ class CGEditor {
   MoveTable *MT;
   Margin *MA;
   Menu *ME;
+  /// @brief To Focus (TF) move to focus on the next draw (nullptr if not used)
+  CMI::HalfMove *TF;
 
 protected:
   Status status;

src/components/Scrollbar.cpp

@@ -1,5 +1,5 @@
 #include "Scrollbar.hpp"
-
+#include <iostream>
 namespace cgeditor {
 Scrollbar::Scrollbar(Status *s, bool IsHorizontal) : Component(s) {
   this->IsHorizontal = IsHorizontal;
@@ -16,9 +16,8 @@ Scrollbar::Scrollbar(Status *s, bool IsHorizontal) : Component(s) {
 
   DragX = 0;
   DragY = 0;
-  CanvasWidth = 0;
-  CanvasHeight = 0;
   Trigger = false;
+  ShouldApplyFocus = false;
 }
 
 void Scrollbar::Refresh() {
@@ -33,23 +32,15 @@ void Scrollbar::Refresh() {
     bg.height = status->CanvasHeight - status->ScrollbarWidth;
     bar.x = bg.x;
   }
-
+  // Init default width and height
   bar.width = bg.width;
   bar.height = bg.height;
 
-  // Check if resize, in this case, reset everything (avoid bugs).
-  // Not that this will be executed during first draw also but it is fine:
-  if((CanvasWidth != status->CanvasWidth) || (CanvasWidth != status->CanvasWidth)){
-    status->ScrollX=0;
-    status->ScrollY=0;
-    bar.x=bg.x;
-    bar.y=bg.y;
-  }
-
   // Compute move table canvas
   double MTCanvasHeight = status->CanvasHeight - status->ScrollbarWidth;
   double MTCanvasWidth = status->CanvasWidth - status->ScrollbarWidth;
 
+  // Configure scrollbar width and height and determined if a scroll must be applied:
   bool shouldScroll = false;
   if (!IsHorizontal && status->MoveTableMaxY > MTCanvasHeight) {
     bar.height =
@@ -62,8 +53,60 @@ void Scrollbar::Refresh() {
     shouldScroll = true;
   }
 
+  // Ensure current scroll is valid (moves deletions, canvas resize etc...)
+  // If not, we correct it now
+  if(IsHorizontal){
+    // Check if we should not scroll but still an offset is applied to coordinates:
+    if(!shouldScroll && status->ScrollX>0){
+      status->ScrollX=0;
+      bar.x=bg.x;
+    }
+    // Else if we should scroll:
+    else if(shouldScroll){
+      double maxScroll=status->MoveTableMaxX-MTCanvasWidth;
+      // Check if we over scroll:
+      if((maxScroll+status->ScrollX)<0){
+        status->ScrollX=-maxScroll;
+        bar.x=bg.width-bar.width;
+      }
+      // If not sensure that scroll bar is at the correct location:
+      else {
+        // We add negative sign because ScrollY is negative:
+        double percent = (-status->ScrollX) / maxScroll;
+        bar.x=(bg.width - bar.width)*percent;
+      }
+    }
+    else {
+      status->ScrollX=0;
+      bar.x=0;
+    }
+  } else {
+    // Here same as previously but for vertical bar!
+    if(!shouldScroll && status->ScrollY>0){
+      status->ScrollY=0;
+      bar.y=bg.y;
+    }
+    else if(shouldScroll){
+      double maxScroll=status->MoveTableMaxY-MTCanvasHeight;
+      if((maxScroll+status->ScrollY)<0){
+        status->ScrollY=-maxScroll;
+        bar.y=bg.height-bar.height;
+      } else {
+        double percent = (-status->ScrollY) / maxScroll;
+        bar.y=(bg.height - bar.height)*percent;
+      }
+    } else {
+      status->ScrollY=0;
+      bar.y=0;
+    }
+  }
+
+  // Handle user scroll events:
   if (shouldScroll) {
-    if (IsHorizontal && status->EventHScroll != 0) {
+    if(ShouldApplyFocus){
+      ApplyFocus();
+    }
+    else if (IsHorizontal && status->EventHScroll != 0) {
       double percent = status->EventHScroll / status->MoveTableMaxX;
       double maxScroll = bg.width - bar.width;
       bar.x += maxScroll * percent;
@@ -119,21 +162,20 @@ void Scrollbar::Refresh() {
   elements.push_back(bg);
   elements.push_back(bar);
   // Update cache:
-  CanvasWidth = status->CanvasWidth;
-  CanvasHeight = status->CanvasHeight;
+  ShouldApplyFocus=false;
 }
 
-void Scrollbar::Focus(double XorY){
+void Scrollbar::ApplyFocus(){
   double MTCanvasHeight = status->CanvasHeight - status->ScrollbarWidth;
   double MTCanvasWidth = status->CanvasWidth - status->ScrollbarWidth;
   // Check horizontal or vertical and if should scroll
   if(IsHorizontal && status->MoveTableMaxX > MTCanvasWidth){
       // First normalize:
-      XorY-=MTCanvasWidth; // Do not scroll on first page
-      XorY=std::max(0.0,XorY); // Ensure focus is greater than 0
-      XorY=std::min(XorY,(status->MoveTableMaxX-MTCanvasWidth)); // Ensure focus is than scroll max
+      FocusX-=MTCanvasWidth; // Do not scroll on first page
+      FocusX=std::max(0.0,FocusX); // Ensure focus is greater than 0
+      FocusX=std::min(FocusX,(status->MoveTableMaxX-MTCanvasWidth)); // Ensure focus is than scroll max
       // Then compute percent and apply scroll
-      double percent = XorY / (status->MoveTableMaxX-MTCanvasWidth);
+      double percent = FocusX / (status->MoveTableMaxX-MTCanvasWidth);
       status->ScrollX =
           -(status->MoveTableMaxX - MTCanvasWidth) * percent;
       // Do not forget to update scrollbar:
@@ -144,11 +186,11 @@ void Scrollbar::Focus(double XorY){
   }
   else if(status->MoveTableMaxY > MTCanvasHeight){
       // First normalize:
-      XorY-=MTCanvasHeight; // Do not scroll on first page
-      XorY=std::max(0.0,XorY); // Ensure focus is greater than 0
-      XorY=std::min(XorY,(status->MoveTableMaxY-MTCanvasHeight)); // Ensure focus is than scroll max
+      FocusY-=MTCanvasHeight; // Do not scroll on first page
+      FocusY=std::max(0.0,FocusY); // Ensure focus is greater than 0
+      FocusY=std::min(FocusY,(status->MoveTableMaxY-MTCanvasHeight)); // Ensure focus is than scroll max
       // Then compute percent and apply scroll
-      double percent = XorY / (status->MoveTableMaxY-MTCanvasHeight);
+      double percent = FocusY / (status->MoveTableMaxY-MTCanvasHeight);
       status->ScrollY =
           -(status->MoveTableMaxY - MTCanvasHeight) * percent;
       // Do not forget to update scrollbar:
@@ -159,4 +201,23 @@ void Scrollbar::Focus(double XorY){
   }
 }
 
+void Scrollbar::Focus(double XorY){
+  if(IsHorizontal)
+    FocusX=XorY;
+  else
+    FocusY=XorY;
+  ShouldApplyFocus=true;
+}
+
+void Scrollbar::Reset(){
+  if(IsHorizontal){
+    status->ScrollX=0;
+    bar.x=bg.x;
+  }else{
+    status->ScrollY=0;
+    bar.y=bg.y;
+  }
+}
+
+
 } // namespace cgeditor

src/components/Scrollbar.hpp

@@ -8,13 +8,19 @@ class Scrollbar : public Component {
   bool IsHorizontal;
   Element bg,bar;
   double DragY,DragX;
+  double FocusX,FocusY;
+  /// @brief Should focus be applied on the next draw
+  bool ShouldApplyFocus;
+  /// @brief Use to detect scrollbar drags
   bool Trigger;
-  /// @brief Canvas size cache used to reset on resize
-  double CanvasWidth, CanvasHeight;
+  /// @brief Goto a given graphical coordinate (if possible using current scroll range)
+  void ApplyFocus();
 public:
   Scrollbar(Status* s,bool IsHorizontal);
   void Refresh();
-  /// @brief Goto a given graphical coordinate (if possible using current scroll range)
+  /// @brief Focus on a coordinate on the next draw
   void Focus(double XorY);
+  /// @brief Undo all scroll operations, go back to the origin
+  void Reset();
 };
 } // namespace cgeditor