Now arrows can be drawn using right clicks and drag

TODO.md

@@ -9,7 +9,7 @@
  
  ## Additional Features
  - [ ] Add a live evaluation bar to the BoardCanvas
- - [ ] Be able to draw arrows on the Board
+ - [x] Be able to draw arrows on the Board
  - [ ] Highlight the last played move
  - [ ] Be able to play against an engine
  - [ ] Implement full chess engine game analyzer/annotator

src/game_tab/left_panel/board/BoardCanvas.cpp

@@ -15,6 +15,7 @@ BoardCanvas::BoardCanvas(wxFrame *parent)
       lock_square_size(false), t(new Theme()), t_captures(new Theme()) {
   is_dragging = false;
   valid_drag = false;
+  valid_arrow = false;
   // Init animation data
   adata.duration=200;
   adata.duration_fast=80;
@@ -45,6 +46,8 @@ BoardCanvas::BoardCanvas(wxFrame *parent)
   Bind(wxEVT_MOTION, &BoardCanvas::MouseEvent, this);
   Bind(wxEVT_LEFT_DOWN, &BoardCanvas::MouseEvent, this);
   Bind(wxEVT_LEFT_UP, &BoardCanvas::MouseEvent, this);
+  Bind(wxEVT_RIGHT_DOWN, &BoardCanvas::MouseEvent, this);
+  Bind(wxEVT_RIGHT_UP, &BoardCanvas::MouseEvent, this);
 }
 
 void BoardCanvas::OnResize(wxSizeEvent &e){
@@ -434,6 +437,19 @@ void BoardCanvas::MouseEvent(wxMouseEvent &event) {
         is_dragging = true;
         Refresh();
       }
+    } else if (valid_arrow && event.RightUp()) {
+      valid_arrow=false;
+      // Handle drop
+      REFRESH_MOUSE_LOCATION();
+      INIT_CURRENT_SQUARE();
+      if (IsCurrentSquareValid) {
+        std::string arrow = ((char)('a' + active_square.x)) +
+                          std::to_string(+active_square.y + 1) +
+                          ((char)('a' + file)) + std::to_string(rank + 1);
+        gs.arrows.push_back(arrow);
+        wxLogDebug("Draw arrow %s",arrow);
+        Refresh();
+      }
     } else {
       if (is_dragging) {
         is_dragging = false;
@@ -457,7 +473,7 @@ void BoardCanvas::MouseEvent(wxMouseEvent &event) {
           Refresh();
         }
       }
-      if (event.LeftDown()) {
+      if (event.LeftDown() || event.RightDown()) {
         SetFocus();
         REFRESH_MOUSE_LOCATION();
         lastClickX = mouseX;
@@ -466,12 +482,22 @@ void BoardCanvas::MouseEvent(wxMouseEvent &event) {
         if (IsCurrentSquareValid) {
           active_square.x = file;
           active_square.y = rank;
-          if (gs.board[(7 - rank) * 8 + file] != ' ') {
+          if(event.LeftDown()){
-            wxLogDebug("Drag start on square (%d,%d)", file, rank);
+            if (gs.board[(7 - rank) * 8 + file] != ' ') {
-            valid_drag = true;
+              wxLogDebug("Drag start on square (%d,%d)", file, rank);
+              valid_drag = true;
+            }
+          }
+          else {
+            wxLogDebug("Arrow start on square (%d,%d)", file, rank);
+            valid_arrow = true;
           }
         }
       }
+      else if(event.LeftUp()){
+        gs.arrows.clear();
+        Refresh();
+      }
     }
   }
   // Let GameTableLeftPanel process mouse wheel events:
@@ -506,6 +532,7 @@ void BoardCanvas::DrawArrow(wxDC &dc, int xsrc, int ysrc, int xdst, int ydst){
   wxPoint vect(xdst-xsrc,ydst-ysrc);
   double length=ceil(sqrt(pow(vect.x,2)+pow(vect.y,2)));
   double angle=acos(vect.x/length);
+  angle= (vect.y>0) ? angle=angle : -angle;
 
   // Compute metrics
   std::uint8_t thickness=50;
@@ -514,8 +541,8 @@ void BoardCanvas::DrawArrow(wxDC &dc, int xsrc, int ysrc, int xdst, int ydst){
 
   // Setup transform matrix
   wxAffineMatrix2D rot_m;
-  rot_m.Rotate(-angle);
+  rot_m.Rotate(angle);
-
+  wxLogDebug("Angle is %d,%d",(int)vect.x,(int)vect.y);
   // Init polygons
   wxPoint tip[]={wxPoint(tail_length,-thickness/2),wxPoint(tail_length,thickness/2),wxPoint(tail_length+tip_height,0)};
   wxPoint tail[]={wxPoint(0,-thickness/4),wxPoint(tail_length,-thickness/4),wxPoint(tail_length,thickness/4),wxPoint(0,thickness/4)};

src/game_tab/left_panel/board/BoardCanvas.hpp

@@ -80,7 +80,7 @@ class BoardCanvas : public wxPanel {
   std::string white_player,black_player;
 
   // Various canvas state variables
-  bool black_side, is_dragging, valid_drag, is_black_turn;
+  bool black_side, is_dragging, valid_drag, valid_arrow, is_black_turn;
   std::uint32_t boardX, boardY, square_width, piece_width, mouseX, mouseY, lastClickX,
       lastClickY;
   wxSize canvas_size;