You can use this function to update the angle of the view camera within the room. You give the unique camera ID value (as returned by the different camera_create functions) and then give the angle that you wish to set the camera view to. The default value is 0° with positive values rotating the camera counter-clockwise, ie: setting the value to 90 will rotate the camera 90° to the left.
Argument Description camera_id The unique camera ID value returned when you created the camera angle The new angle to set the camera view to
camera_set_view_angle(view_camera, point_direction(x, y, mouse_x, mouse_y));
The above code will set the view camera angle for the camera assigned to view port.