HCMP Messaging (alpha 0.1)
OSC message
OSC message is used to control the conductor directly, by which one can use a external device to control playback and tempo. Since OSC messages are based on UDP, such messages are functionally limited and assumed to be transfered locally.
Address is: /hcmp
Message content: one integer.
| Type |
Message |
Comments |
| Tap |
-3 |
Indicate a beat point to the conductor. |
| Play |
-1 |
start conducting |
| Stop |
-2 |
stop conducting and tell the players to stop |
| Cue |
0 ~ 999 |
Let the conductor to send a cue to players. |
ZMQ message
- Messages are in Strings and are separated by whitespace " ".
- In one message, the first String is fixed to "Hcmp".
- The second string is the operation's identifier, for example, tm (for updating time map)
- The next several strings are parameters, which in this version are all converted to Strings.
The following table shows the messages used by HCMP. Note that <something> means a number and the "something" inside is the variable's name.
Control Messages
| Type |
Direction |
Message |
Comments |
| Play |
c->p* |
play |
start playing |
| Stop |
c->p |
stop |
stop playing |
| Update time-map |
c->p |
tm k b |
Send new time-map (vtime = rtime * k + b) to the player |
| Set Position |
c->p |
pos vtime |
set position to beat vtime |
| PlayAll |
p->c** |
ID *** play |
indicate the conductor to play |
| StopAll |
p->c |
ID stop |
indicate the conductor to stop |
| Ready |
p->c |
ID ready |
tell the conductor that this player is ready to play |
| Position |
p->c |
ID pos vtime |
indicate the conductor to go to position vtime |
* c->p means from conductor to player
** p->c means from player to conductor
*** the ID of the player.
Clock Sync Messages
| Type |
Direction |
Message |
Comments |
| ReSync/StartSync |
p->c |
resync |
Phase 1: tell the conductor to start clock sync |
| Send Conductor Time |
c->p |
cclk time |
Phase 2: tell the player clock sync starts and send conductor's local time by time |
| Send Player's Time |
p->c |
pclk time |
Phase 3: send the conductor the player's local time |
| Send Player Latency |
c->p |
clat latency |
Phase 4: send the latency between sending cclk and receiving pclk to the player. |
