window moving and focusing

applications/goldman/source/input.cpp

@@ -5,15 +5,51 @@
 
   euler::syscall::set_thread_name("input thread");
 
+  window *window_being_moved = 0;
+  bool was_mouse_down_before = false;
+
   while (true) {
 
     auto result = euler::syscall::get_input_packet();
     if (std::holds_alternative<euler::syscall::mouse_packet>(result)) {
       auto packet = std::get<euler::syscall::mouse_packet>(result);
+
       r->lock();
+
+      int old_x, old_y;
+      r->get_cursor(old_x, old_y);
       r->bump_cursor(packet.x_changed, packet.y_changed);
+      int new_x, new_y;
+      r->get_cursor(new_x, new_y);
+
+      if (window_being_moved != 0) {
+        if (r->windows.size() == 0 || r->windows.back() != window_being_moved)
+          window_being_moved = 0;
+        else {
+          r->windows.back()->x += new_x - old_x;
+          r->windows.back()->y += new_y - old_y;
+          if (!packet.left_button_down)
+            window_being_moved = 0;
+        }
+      }
+
+      else if (packet.left_button_down && !was_mouse_down_before)
+        for (auto it = r->windows.rbegin(); it != r->windows.rend(); ++it)
+          if (new_x >= (*it)->x && new_y >= (*it)->y &&
+              new_x < (*it)->x + (*it)->contents_with_decorations. width &&
+              new_y < (*it)->y + (*it)->contents_with_decorations.height) {
+            r->move_window_to_front(--it.base());
+            //it is now invalidated, but our window is now r->windows.back()
+            if (new_y < r->windows.back()->y + window::title_height)
+              window_being_moved = r->windows.back();
+            break;
+          }
+
       r->unlock();
       r->dispatch_render();
+
+      was_mouse_down_before = packet.left_button_down;
+
     }
 
   }

applications/goldman/source/renderer.cpp

@@ -49,14 +49,15 @@ void renderer::do_render() {
 
   double_buffer.copy_from(background, 0, 0);
 
-  for (auto it = windows.begin(); it != windows.end(); ++it)
-
+  for (auto it = windows.begin(); it != windows.end(); ++it) {
+    int tx = (*it)->x, ty = (*it)->y, fx = 0, fy = 0;
+    int w = (*it)->contents_with_decorations.width;
+    int h = (*it)->contents_with_decorations.height;
+    daguerre::make_safe(tx, fx, w, 0, double_buffer.width);
+    daguerre::make_safe(ty, fy, h, 0, double_buffer.height);
     double_buffer.copy_from(
-      (*it)->contents_with_decorations, (*it)->x, (*it)->y, 0, 0,
-      std::min((*it)->contents_with_decorations.width,
-               double_buffer.width - (*it)->x),
-      std::min((*it)->contents_with_decorations.height,
-               double_buffer.height - (*it)->y));
+      (*it)->contents_with_decorations, tx, ty, fx, fy, w, h);
+  }
 
   double_buffer.convert_from(
     cursor_background, cursor, cursor_x, cursor_y, 0, 0,
@@ -79,6 +80,11 @@ void renderer::do_render() {
   }
 }
 
+void renderer::get_cursor(int &x_out, int &y_out) {
+  x_out = cursor_x;
+  y_out = cursor_y;
+}
+
 void renderer::bump_cursor(int x_offset, int y_offset) {
 
   cursor_x += x_offset;
@@ -95,6 +101,15 @@ void renderer::bump_cursor(int x_offset, int y_offset) {
 
 }
 
+void renderer::move_window_to_front(std::list<window *>::iterator w) {
+  window *wp = *w;
+  windows.erase(w);
+  if (windows.size() != 0)
+    windows.back()->draw_decorations(false);
+  windows.push_back(wp);
+  wp->draw_decorations(true);
+}
+
 void renderer::add_window(window *w) {
   if (windows.size() != 0)
     windows.back()->draw_decorations(false);

applications/goldman/source/renderer.hpp

@@ -17,9 +17,6 @@ class renderer {
   int cursor_x;
   int cursor_y;
 
-  //bottom to top
-  std::list<window *> windows;
-
   std::mutex mut;
 
   euler::syscall::stream_handle
@@ -28,6 +25,12 @@ class renderer {
   void do_render();
 
 public:
+  //all of the shown windows, sorted from furthest back to furthest front.
+  //while the renderer is not locked, the contents of this can change and
+  //iterators can be invalided. this should not be reordered, added to, or
+  //have elements removed from outside the renderer.
+  std::list<window *> windows;
+
   renderer(
     daguerre::image<daguerre::hilbert_color> &&framebuffer,
     daguerre::image<daguerre::hilbert_color> &&background,
@@ -53,8 +56,19 @@ public:
     euler::syscall::write_to_stream(dispatcher_handle_1, 1, &byte);
   }
 
+  //gets the current position of the cursor. this should
+  //only be called while the renderer is locked.
+  void get_cursor(int &x_out, int &y_out);
+
+  //this adds x_offset and y_offset to the current cursor position, and then
+  //clamps the cursor position to have its top-left pixel inside the frame.
+  //this should only be called while the renderer is locked.
   void bump_cursor(int x_offset, int y_offset);
 
+  //moves the pointed to window to the front of the window stack.
+  //this should only be called while the renderer is locked.
+  void move_window_to_front(std::list<window *>::iterator w);
+
   void    add_window(window *w);
   void remove_window(window *w);
 

applications/goldman/source/socket.cpp

@@ -129,7 +129,10 @@ struct socket_state {
 
   euler::syscall::set_thread_name("socket thread");
 
-  window *w = new window();
+  int x, y;
+  r->get_cursor(x, y);
+
+  window *w = new window(x, y);
   socket_state *state = new socket_state {
     .socket = socket, .w = w };
 

applications/goldman/source/window.cpp

@@ -11,12 +11,16 @@ daguerre::hilbert_color border_color_not_top;
 daguerre::hilbert_color title_color;
 
 void window::set_size(int width, int height) {
+  int center_x = x + contents_with_decorations. width / 2;
+  int center_y = y + contents_with_decorations.height / 2;
   contents_with_decorations =
     daguerre::image<daguerre::hilbert_color>(width + 4, height + 18);
   contents = daguerre::image<daguerre::hilbert_color>(
     width, height,
     &contents_with_decorations.at(2, 16),
     contents_with_decorations.buffer_pitch, false);
+  x = center_x - contents_with_decorations. width / 2;
+  y = center_y - contents_with_decorations.height / 2;
 }
 
 void title_converter(
@@ -40,6 +44,7 @@ void window::draw_decorations(bool top) {
 
   static_assert( decorations_extra_width ==  4);
   static_assert(decorations_extra_height == 18);
+  static_assert(            title_height == 16);
 
   auto border_color = top ? border_color_top : border_color_not_top;
 

applications/goldman/source/window.hpp

@@ -6,6 +6,7 @@ struct window {
 
   static constexpr int decorations_extra_width  =  4;
   static constexpr int decorations_extra_height = 18;
+  static constexpr int title_height = 16;
 
   daguerre::image<daguerre::hilbert_color> contents_with_decorations;
   daguerre::image<daguerre::hilbert_color> contents;
@@ -20,7 +21,10 @@ struct window {
   void set_size(int width, int height);
   void draw_decorations(bool top);
 
-  inline window() : x(0), y(0), is_shown(false) {
+  inline window(int center_x, int center_y)
+  : x(center_x - decorations_extra_width / 2),
+    y(center_y - decorations_extra_height / 2),
+    is_shown(false) {
     set_size(0, 0);
     draw_decorations(false);
   }

euler/include/std/list.hpp

@@ -1,10 +1,11 @@
 #pragma once
 
+#include <iterator>
 #include <memory>
 
 namespace std {
 
-  template <class T, class Allocator = std::allocator<T>>
+  template <class T>
   class list {
 
   public:
@@ -18,6 +19,13 @@ namespace std {
     struct generic_iterator {
 
       node *the_node;
+      node *last_node;
+
+      using iterator_category = std::bidirectional_iterator_tag;
+      using reference = V &;
+      using pointer = V *;
+      using value_type = V;
+      using difference_type = size_t;
 
       bool operator ==(const generic_iterator &other) const {
         return the_node == other.the_node;
@@ -40,11 +48,29 @@ namespace std {
         return *this;
       }
 
+      generic_iterator &operator --() {
+        if (the_node == 0)
+          the_node = last_node;
+        else
+          the_node = the_node->prev;
+        return *this;
+      }
+
+      generic_iterator operator -(size_t count) const {
+        generic_iterator it = { .the_node = the_node };
+        for (size_t i = 0; i < count; ++i)
+          --it;
+        return it;
+      }
+
     };
 
     using       iterator = generic_iterator<      T>;
     using const_iterator = generic_iterator<const T>;
 
+    using       reverse_iterator = std::reverse_iterator<      iterator>;
+    using const_reverse_iterator = std::reverse_iterator<const_iterator>;
+
   private:
     node *first_node;
     node *last_node;
@@ -79,17 +105,101 @@ namespace std {
       if (n->next) n->next->prev = n->prev;
       else             last_node = n->prev;
       delete n;
-      return iterator { .the_node = r };
+      return iterator {
+        .the_node = r,
+        .last_node = last_node
+      };
     }
 
-    iterator begin() noexcept { return iterator { .the_node = first_node }; }
-    iterator   end() noexcept { return iterator { .the_node = 0 }; }
+    iterator begin() noexcept {
+      return iterator {
+        .the_node = first_node,
+        .last_node = last_node
+      };
+    }
 
-    const_iterator begin() const noexcept { return iterator { .the_node = first_node }; }
-    const_iterator   end() const noexcept { return iterator { .the_node = 0 }; }
+    iterator end() noexcept {
+      return iterator {
+        .the_node = 0,
+        .last_node = last_node
+      };
+    }
 
-    const_iterator cbegin() const noexcept { return iterator { .the_node = first_node }; }
-    const_iterator   cend() const noexcept { return iterator { .the_node = 0 }; }
+    const_iterator begin() const noexcept {
+      return iterator {
+        .the_node = first_node,
+        .last_node = last_node
+      };
+    }
+
+    const_iterator end() const noexcept {
+      return iterator {
+        .the_node = 0,
+        .last_node = last_node
+      };
+    }
+
+    const_iterator cbegin() const noexcept {
+      return iterator {
+        .the_node = first_node,
+        .last_node = last_node
+      };
+    }
+
+    const_iterator cend() const noexcept {
+      return iterator {
+        .the_node = 0,
+        .last_node = last_node
+      };
+    }
+
+    reverse_iterator rbegin() noexcept {
+      return reverse_iterator(
+        iterator {
+          .the_node = 0,
+          .last_node = last_node
+        });
+    }
+
+    reverse_iterator rend() noexcept {
+      return reverse_iterator(
+        iterator {
+          .the_node = first_node,
+          .last_node = last_node
+        });
+    }
+
+    const_reverse_iterator rbegin() const noexcept {
+      return const_reverse_iterator(
+        iterator {
+          .the_node = 0,
+          .last_node = last_node
+        });
+    }
+
+    const_reverse_iterator rend() const noexcept {
+      return const_reverse_iterator(
+        iterator {
+          .the_node = first_node,
+          .last_node = last_node
+        });
+    }
+
+    const_reverse_iterator crbegin() const noexcept {
+      return const_reverse_iterator(
+        iterator {
+          .the_node = 0,
+          .last_node = last_node
+        });
+    }
+
+    const_reverse_iterator crend() const noexcept {
+      return const_reverse_iterator(
+        iterator {
+          .the_node = first_node,
+          .last_node = last_node
+        });
+    }
 
     size_t remove(const T &value) {
       size_t removed = 0;