win-capture: Fix display capture capturing on create

Prevents Display capture from capturing the first display on creation.
This issue is due to the properties view combo box automatically
selecting the first item in the list by default, but this needs explicit
text anyway to indicate display, so this adds a "[Select a display]"
item that will prevent that from happening and tell the user to select a
display.

plugins/win-capture/data/locale/en-US.ini

@@ -43,6 +43,7 @@ CaptureAudio="Capture Audio (BETA)"
 CaptureAudio.TT="When enabled, creates an \"Application Audio Capture\" source that automatically updates to the currently captured window/application.\nNote that if Desktop Audio is configured, this could result in doubled audio."
 AudioSuffix="Audio"
 SelectAWindow="[Select a window to capture]"
+SelectADisplay="[Select a display to capture]"
 
 # Generic compatibility messages
 Compatibility.GameCapture.Admin="%name% may require OBS to be run as admin to use Game Capture."

plugins/win-capture/duplicator-monitor-capture.c

@@ -38,6 +38,8 @@
 
 #define RESET_INTERVAL_SEC 3.0f
 
+#define INVALID_DISPLAY "DUMMY"
+
 typedef BOOL (*PFN_winrt_capture_supported)();
 typedef BOOL (*PFN_winrt_capture_cursor_toggle_supported)();
 typedef struct winrt_capture *(*PFN_winrt_capture_init_monitor)(
@@ -416,7 +418,7 @@ static void duplicator_capture_destroy(void *data)
 static void duplicator_capture_defaults(obs_data_t *settings)
 {
 	obs_data_set_default_int(settings, "method", METHOD_AUTO);
-	obs_data_set_default_string(settings, "monitor_id", "DUMMY");
+	obs_data_set_default_string(settings, "monitor_id", INVALID_DISPLAY);
 	obs_data_set_default_int(settings, "monitor_wgc", 0);
 	obs_data_set_default_bool(settings, "capture_cursor", true);
 	obs_data_set_default_bool(settings, "force_sdr", false);
@@ -905,6 +907,13 @@ static obs_properties_t *duplicator_capture_properties(void *data)
 		props, "monitor_id", TEXT_MONITOR, OBS_COMBO_TYPE_LIST,
 		OBS_COMBO_FORMAT_STRING);
 
+	if (capture && strcmp(capture->monitor_id, INVALID_DISPLAY) == 0) {
+		obs_property_list_add_string(monitors,
+					     obs_module_text("SelectADisplay"),
+					     INVALID_DISPLAY);
+		obs_property_list_item_disable(monitors, 0, true);
+	}
+
 	obs_properties_add_bool(props, "capture_cursor", TEXT_CAPTURE_CURSOR);
 	obs_properties_add_bool(props, "force_sdr", TEXT_FORCE_SDR);