20050923Working Diary-- user defined message in Openh323-优快云博客

博客记录了在openh323中找到发送用户自定义消息的方法，如会议成员列表等。还成功为虚拟会议系统添加运行时根据参会人数改变视频显示数量的功能，修改消息传输机制，在服务器和客户端间用特定方法传消息，动态增减3D场景视频显示。

am:

Found the method in openh323 to send user defined messages, such like the conference member list, member names......:

H323Connection::SendUserInputIndication -- send user defined message
H323Connection::OnUserInputIndication -- auto receive user defined message

pm:

I successed added the function that the Virtual Meeting system could at run time change the number of video displayed, depending on the number of participantants of conference.

Modified the message transfering mechanism, delivering the joining and leaving of member to every members left. Using following methods to transfer message between server and client.
- OnUserInputString( on client )
- SendUserInput( on server )
Got number of members of conference when the number is changed. Here we used a small skill. Because the control message need to be placed mixing with common user input message, we added key words in the message and abstracted it to get the control commands
Dynamicly increased or decreased the displayed video in 3D scene according to the number of members. All the manipulations fastened on the function CVideoTexture3D::Render, in which the video is calculated and rendered.