Support for inverted selections.

include/ftxui/component/screen_interactive.hpp

@@ -138,7 +138,10 @@ class ScreenInteractive : public Screen {
   // Selection API:
   bool selection_enabled_ = false;
   CapturedMouse selection_pending_;
-  Box selection_box_;
+  int selection_start_x_ = 0;
+  int selection_start_y_ = 0;
+  int selection_end_x_ = 0;
+  int selection_end_y_ = 0;
 
   friend class Loop;
 

include/ftxui/dom/node.hpp

@@ -9,6 +9,7 @@
 #include <vector>  // for vector
 
 #include "ftxui/dom/requirement.hpp"  // for Requirement
+#include "ftxui/dom/selection.hpp"    // for Selection
 #include "ftxui/screen/box.hpp"       // for Box
 #include "ftxui/screen/screen.hpp"
 
@@ -43,7 +44,7 @@ class Node {
 
   // Step 3: (optional) Selection
   //         Propagated from Parents to Children.
-  virtual void Selection(Box selection, std::vector<Box>* selected);
+  virtual void Select(Selection& selection);
 
   // Step 4: Draw this element.
   virtual void Render(Screen& screen);
@@ -66,7 +67,7 @@ class Node {
 
 void Render(Screen& screen, const Element& element);
 void Render(Screen& screen, Node* node);
-void Render(Screen& screen, Node* node, Box selection);
+void Render(Screen& screen, Node* node, Selection& selection);
 
 }  // namespace ftxui
 

include/ftxui/dom/selection.hpp

@@ -0,0 +1,33 @@
+// Copyright 2024 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+
+#ifndef FTXUI_DOM_SELECTION_HPP
+#define FTXUI_DOM_SELECTION_HPP
+
+#include "ftxui/screen/box.hpp"  // for Box
+
+namespace ftxui {
+
+/// @brief Represent a selection in the terminal.
+class Selection {
+ public:
+  Selection(int start_x, int start_y, int end_x, int end_y);
+  const Box& GetBox() const;
+
+  Selection SaturateHorizontal(Box box);
+  Selection SaturateVertical(Box box);
+
+
+ private:
+  Selection* const parent_ = nullptr;
+  const int start_x_;
+  const int start_y_;
+  const int end_x_;
+  const int end_y_;
+  const Box box_;
+};
+
+}  // namespace ftxui
+
+#endif /* end of include guard: FTXUI_DOM_SELECTION_HPP */