Establish a control connection to an external device or process.


pfield = makeconnection(“connection_type”[, arg1, arg2, …])

Parameters inside the [brackets] are optional.


makeconnection is a utility command used to associate data coming from “outside” RTcmix with a pfield-handle variable. This variable can then be used to deliver values to an Instrument during scorefile execution. This is very similar to the mechanism used by the maketable scorefile command to deliver table data to Instruments through table-handle variables. Indeed, table-handles and pfield-handles are nearly identical in terms of scorefile use and behavior. The main difference is that table-handle variables are accessing values from a previously-created table, while pfield-handle variables are funneling (in real-time) data from some external process of device into RTcmix.

This is almost the inverse of how the ‘embedded’ RTcmix object works. The RTcmix object can be used inside another application, with all interface tasks mediated through the “wrapping” application. RTcmix is a subsidiary object in this case. makeconnection allows an interface application to be developed within RTcmix, with the interface code existing as a PField class object. Interfaces can then be “connected” to control different Instrument/note parameters through a pfield-handle.

Because device and interface characteristics can vary widely, the syntax of a makeconnection command will also be relatively unique for particular interfaces. At present, three different connection_type interfaces are included in RTcmix.

Many of the arguments for makeconnection may themselves also be pfield-handles.


Connection Types


pan = makeconnection("mouse", "x", 1, 0, .5, lag=50, "pan")
deltime = makeconnection("mouse", "x", .2, .5, .5, lag=90, "delay time", "", 5)
feedback = makeconnection("mouse", "y", 0, 1, 0, lag=20, "feedback")
DELAY(0, 0, 10, 1.0, deltime, feedback, 1.0, 0, pan)

This scorefile uses three different pfield-handle variables: pan, deltime and feedback. pan and deltime are controlled by the ‘x’ position of the mouse, scaled by the min and max values for each ([1, 0], [0.0002, 0.5]). The deltime parameter is set with a high lag percentage to prevent glitching as the delay-time of the DELAY instrument is changed. The feedback parameter tracks the ‘y’ position of the mouse, scaling values between 0 and 1. Notice that these pfield-handle variables function in the same way that maketable table-handle variables do.

See the RTcmix/docs/sample\_scores/dynamic\_insts/ subdirectory in the RTcmix distrubition for more examples of different connection types.


The makeconnection command will dynamically-load the library containing the interface code used for each connection type. For example:

makeconnection("mouse", ...)

will look for the dynamic library As discussed above, this library needs to be locatable along the RTcmix library search path. The default RTcmix installation will compile and install this library into the RTcmix/shlib/ directory.

See Also

maketable, makeLFO, makerandom, makefilter, makeconverter, makemonitor