[client] add new option input:captureOnFocus

This option allows the client to automatically enter capture mode if the
window is focused.

Closes #1088

client/src/app.c

@@ -95,6 +95,9 @@ void app_updateCursorPos(double x, double y)
 
 void app_handleFocusEvent(bool focused)
 {
+  if (g_state.focused == focused)
+    return;
+
   g_state.focused = focused;
 
   // release any imgui buttons/keys if we lost focus
@@ -126,6 +129,9 @@ void app_handleFocusEvent(bool focused)
     if (g_params.minimizeOnFocusLoss)
       g_state.ds->minimize();
   }
+  else
+    if (g_params.captureOnFocus)
+      core_setGrab(true);
 
   g_cursor.realign = true;
   g_state.ds->realignPointer();

client/src/config.c

@@ -297,6 +297,13 @@ static struct Option options[] =
   },
 
   // input options
+  {
+    .module         = "input",
+    .name           = "captureOnFocus",
+    .description    = "Enable capture mode when the window becomes focused",
+    .type           = OPTION_TYPE_BOOL,
+    .value.x_bool   = false
+  },
   {
     .module         = "input",
     .name           = "grabKeyboard",
@@ -664,6 +671,7 @@ bool config_load(int argc, char * argv[])
     case 270: g_params.winRotate = LG_ROTATE_270; break;
   }
 
+  g_params.captureOnFocus         = option_get_bool("input", "captureOnFocus"        );
   g_params.grabKeyboard           = option_get_bool("input", "grabKeyboard"          );
   g_params.grabKeyboardOnFocus    = option_get_bool("input", "grabKeyboardOnFocus"   );
   g_params.releaseKeysOnFocusLoss = option_get_bool("input", "releaseKeysOnFocusLoss");

client/src/main.h

@@ -186,6 +186,7 @@ struct AppParams
   bool                 ignoreQuit;
   bool                 noScreensaver;
   bool                 autoScreensaver;
+  bool                 captureOnFocus;
   bool                 grabKeyboard;
   bool                 grabKeyboardOnFocus;
   int                  escapeKey;