Hide Shortcut Guide when screenshots are taken (#605)

src/modules/shortcut_guide/overlay_window.cpp

@@ -385,6 +385,16 @@ void D2DOverlayWindow::set_theme(const std::wstring& theme) {
   }
 }
 
+/* Hide the window but do not call on_hide(). Use this to quickly hide the window when needed.
+   Note, that a proper hide should be made after this before showing the window again.
+*/
+void D2DOverlayWindow::quick_hide() {
+  ShowWindow(hwnd, SW_HIDE);
+  if (thumbnail) {
+    DwmUnregisterThumbnail(thumbnail);
+  }
+}
+
 float D2DOverlayWindow::get_overlay_opacity() {
   return overlay_opacity;
 }

src/modules/shortcut_guide/overlay_window.h

@@ -47,6 +47,7 @@ public:
   ~D2DOverlayWindow();
   void apply_overlay_opacity(float opacity);
   void set_theme(const std::wstring& theme);
+  void quick_hide();
 private:
   void animate(int vk_code, int offset);
   bool show_thumbnail(const RECT& rect, double alpha);

src/modules/shortcut_guide/shortcut_guide.cpp

@@ -146,6 +146,10 @@ void OverlayWindow::on_held_press(DWORD vkCode) {
   winkey_popup->animate(vkCode);
 }
 
+void OverlayWindow::quick_hide() {
+  winkey_popup->quick_hide();
+}
+
 void OverlayWindow::was_hidden() {
   target_state->was_hiden();
 }

src/modules/shortcut_guide/shortcut_guide.h

@@ -23,6 +23,7 @@ public:
 
   void on_held();
   void on_held_press(DWORD vkCode);
+  void quick_hide();
   void was_hidden();
 
   virtual void destroy() override;

src/modules/shortcut_guide/target_state.cpp

@@ -11,6 +11,12 @@ bool TargetState::signal_event(unsigned vk_code, bool key_down) {
   if (!events.empty() && events.back().key_down == key_down && events.back().vk_code == vk_code) {
     return false;
   }
+  // Hide the overlay when WinKey + Shift + S is pressed. 0x53 is the VK code of the S key
+  if (key_down && state == Shown && vk_code == 0x53 && (GetKeyState(VK_LSHIFT) || GetKeyState(VK_RSHIFT))) {
+    // We cannot use normal hide() here, there is stuff that needs deinitialization.
+    // It can be safely done when the user releases the WinKey.
+    instance->quick_hide();
+  }
   bool supress = false;
   if (!key_down && (vk_code == VK_LWIN || vk_code == VK_RWIN) &&
     state == Shown &&