Producing Csound scores with BP2

First select the "Csound" option in the "Output" menu. This option is saved with the settings of the current project or data. If the "MIDI" option is still active, musical items will be played on MIDI and then the user will be prompted to go for a Csound score. If "MIDI" is inactive Csound scores are immediately saved to a file. (See more options Fig.33.)

If Csound is running on a Unix or Windows machine it is a good idea to change the file format to "DOS" or "Unix". The dialog for MIDI and Csound file saving options is visible after typing cmd-option space ("Settings" in the "Windows" menu).

On the top "Settings" dialog, checking "Trace Csound" requests BP2 to display a copy of the score in the "Trace" window. A good idea for a first check-up.

BP2 creates a Csound score of musical items selected in a text window (a "BP2 score") or produced by a grammar. The components of these musical items are sound-objects and/or simple notes. A sound-object contains a sequence of elementary events that may be described as a MIDI stream, a Csound score, or both.

In the latter case, BP2 checks that the durations of the MIDI and Csound sequences are identical. It makes sense to have both descriptions generate similar sounds on MIDI and Csound, so that MIDI is used for an immediate check and Csound for the final material.

• When sound-objects contain Csound scores, their MIDI streams are ignored and the final score is a rearrangement of these score lines with appropriate changes in the timings of events and the values of their parameters. (See §17.8)
• When a MIDI stream is used as the input (which is always the case with simple notes), BP2 does its best to convert MIDI messages to Csound score lines. (See §17.3)
In both cases BP2 needs information about the parameter locations and ranges for each instrument of the Csound orchestra file. Unfortunately, reading the orchestra file would not yield the required information unless it is prepared in a comprehensive way. (Csound designers might think of new instructions in Csound orchestra files that would make this information directly accessible :-) This partial description of Csound instruments is entered in the "Csound instruments" dialog and saved to a "-cs.<name>" file.

Version 2.9.3 of BP2 inserts function tables into the score when necessary, thus enabling arbitrary variations of continuous parameters within a single Csound event (a score line).