Uploading WayPoints , Spline Waypoints to apm

Hello Everyone

I’am building my mini GCS , I had Arm/Disarm are working correctly.
but i’am stuck in how to send the waypoints to my drone, i need to send a Spline waypoints .
i’ve tried MAV_CMD_NAV_SPLINE_WAYPOINT and set parameters as required but it does not send anything to my drone .
here is my code

MAVLink.mavlink_command_long_t alaa = new MAVLink.mavlink_command_long_t();
alaa.target_system = 1;
alaa.target_component = 1;
alaa.command = (ushort)MAV_CMD.MAV_CMD_NAV_SPLINE_WAYPOINT;
alaa.param1 = 0; // hold time
alaa.param4 = 0; // yaw angle
alaa.param5 = latt; // desired latitude
alaa.param6 = longg; // desired longitude
alaa.param7 = altt; // desired altitude
byte[] packet = mavAlaaWrite.GenerateMAVLinkPacket10(MAVLink.MAVLINK_MSG_ID.COMMAND_LONG, alaa);
Serial.Write(packet, 0, packet.Length);

so can someone please make a simple example by sending mission spline waypoints to my drone by clicking on a command button ?

i’am programming using c# windows forms.

Many Thanks in Advance.

@Michael_Oborne
would you please help me with that ?

What autopilot hardware are you using? What version of arducopter and mission planner?
Not all versions support spline waypoints.

Dear @xfacta
Thank you so much for your reply , I have APM 2.6 and APM 2.8 ( Ardupilot Mega ) as a hardware autopilot one of them can be used, as a ground control station I’m implementing my own GCS similar to mission planner.

All I need is how to upload waypoints no problem if they are not spline waypoints , it is Ok for regular waypoints if you can help.

It’s beyond my experience, but you might find what you need in the development docs
http://ardupilot.org/dev/index.html

Also those APM’s are old and wont support recent Arducopter versions and wont support spline waypoints.
If you want to continue using them, just use ordinary waypoints.

@xfacta I’v read all the contents of the link you have commented and much more before posting my request.
Ordinary waypoints are ok i just need to know how to send them.