Ability to get and set transition duration

PROTOCOL.md

@@ -43,6 +43,7 @@ The protocol in general is based on the OBS Remote protocol created by Bill Hami
     - ["GetTransitionList"](#gettransitionlist)
     - ["GetCurrentTransition"](#getcurrenttransition)
     - ["SetCurrentTransition"](#setcurrenttransition)
+    - ["SetTransitionDuration"](#settransitionduration)
     - ["SetVolume"](#setvolume)
     - ["GetVolume"](#getvolume)
     - ["SetMute"](#setmute)
@@ -328,6 +329,7 @@ Get the name of the currently selected transition in the frontend's dropdown men
 __Request fields__ : none  
 __Response__ : always OK, with these additional fields :
 - **"name"** (string) : name of the selected transition
+- **"duration"** (integer, only if transition supports this) : transition duration
 
 *New in OBS Studio*  
 
@@ -343,6 +345,18 @@ __Response__ : OK if specified transition exists, error otherwise.
 
 ---
 
+#### "SetTransitionDuration"
+Set the duration of the currently selected transition.
+
+__Request fields__ :
+- **"duration"** (integer) : desired transition duration in milliseconds
+
+__Response__ : always OK.
+
+*New in OBS Studio*
+
+---
+
 #### "SetVolume"
 Set the volume of a specific source.
 

Utils.cpp

@@ -18,6 +18,8 @@ with this program. If not, see <https://www.gnu.org/licenses/>
 
 #include "Utils.h"
 #include <obs-frontend-api.h>
+#include <QMainWindow>
+#include <QSpinBox>
 #include "obs-websocket.h"
 
 obs_data_array_t* string_list_to_array(char** strings, char* key)
@@ -207,6 +209,32 @@ obs_data_array_t* Utils::GetProfiles()
 	return list;
 }
 
+int Utils::GetTransitionDuration()
+{
+	QMainWindow *window = (QMainWindow*)obs_frontend_get_main_window();
+	QSpinBox* durationControl = window->findChild<QSpinBox*>("transitionDuration");
+
+	if (durationControl)
+	{
+		return durationControl->value();
+	}
+	else
+	{
+		return -1;
+	}
+}
+
+void Utils::SetTransitionDuration(int ms)
+{
+	QMainWindow *window = (QMainWindow*)obs_frontend_get_main_window();
+	QSpinBox* durationControl = window->findChild<QSpinBox*>("transitionDuration");
+
+	if (durationControl && ms >= 0)
+	{
+		durationControl->setValue(ms);
+	}
+}
+
 const char* Utils::OBSVersionString() {
 	uint32_t version = obs_get_version();
 

Utils.h

@@ -37,6 +37,9 @@ class Utils
 		static obs_data_array_t* GetSceneCollections();
 		static obs_data_array_t* GetProfiles();
 
+		static int GetTransitionDuration();
+		static void SetTransitionDuration(int ms);
+
 		static const char* OBSVersionString();
 };
 

WSRequestHandler.cpp

@@ -49,6 +49,7 @@ WSRequestHandler::WSRequestHandler(QWebSocket *client) :
 	messageMap["GetTransitionList"] = WSRequestHandler::HandleGetTransitionList;
 	messageMap["GetCurrentTransition"] = WSRequestHandler::HandleGetCurrentTransition;
 	messageMap["SetCurrentTransition"] = WSRequestHandler::HandleSetCurrentTransition;
+	messageMap["SetTransitionDuration"] = WSRequestHandler::HandleSetTransitionDuration;
 
 	messageMap["SetVolume"] = WSRequestHandler::HandleSetVolume;
 	messageMap["GetVolume"] = WSRequestHandler::HandleGetVolume;
@@ -360,6 +361,11 @@ void WSRequestHandler::HandleGetCurrentTransition(WSRequestHandler *owner)
 	obs_data_t *response = obs_data_create();
 	obs_data_set_string(response, "name", obs_source_get_name(current_transition));
 	
+	if (!obs_transition_fixed(current_transition))
+	{
+		obs_data_set_int(response, "duration", Utils::GetTransitionDuration());
+	}
+
 	owner->SendOKResponse(response);
 
 	obs_data_release(response);
@@ -384,6 +390,13 @@ void WSRequestHandler::HandleSetCurrentTransition(WSRequestHandler *owner)
 	}
 }
 
+void WSRequestHandler::HandleSetTransitionDuration(WSRequestHandler *owner)
+{
+	int ms = obs_data_get_int(owner->_requestData, "duration");
+	Utils::SetTransitionDuration(ms);
+	owner->SendOKResponse();
+}
+
 void WSRequestHandler::HandleSetVolume(WSRequestHandler *owner)
 {
 	const char *item_name = obs_data_get_string(owner->_requestData, "source");

WSRequestHandler.h

@@ -78,6 +78,8 @@ class WSRequestHandler : public QObject
 		static void HandleSetCurrentProfile(WSRequestHandler *owner);
 		static void HandleGetCurrentProfile(WSRequestHandler *owner);
 		static void HandleListProfiles(WSRequestHandler *owner);
+
+		static void HandleSetTransitionDuration(WSRequestHandler *owner);
 };
 
 #endif // WSPROTOCOL_H