> Why is it important to keep the API simple, shouldn't it be functional in first place and make the API usage simply?
Who says a simple API can't be functional? > Anyway (IMHO), there should really be an API which combines audio and MIDI playback, recording and timing of events and makes it possible to keep MIDI in sync with audio (ALSA sequencer API seems to support only tick and time synchronization modes, no audio clock sync mode). Professional API's like ASIO and VST (and DirectMusic) synchronizes everything to audio clock (sample position). Even when MTC is used the audio clock is the main clock source, digital I/O or world clock is used to sync the audio clock to the audio clock of the external device. There is no need for other sync modes than audio (_maybe the tick mode could be useful if ALSA takes care of sending MIDI clock, SPP, MTC etc. data to external devices). Sequencer application can easily convert sample position from the beginning of the song to measures / beats, time etc. whatever is needed when the time signature, tempo and sample rate is known - reading the sample position from the sound card is no problem at all! Well, I disagree. I think using UST is better. You might want to use MIDI without audio. Also MIDI hardware that supports scheduling will not support scheduling to the audio position. Using UST just means mapping different clocks to one common clock. > , PCI chipset's DMA registers have usually such current play position register, or if not, the sample position can be calculated by measuring the time between IRQ's and calculating the time between current time and the time when last interrupt was received. The current sample position does not tell me anything about when some earlier sample occured or a later sample will occur. In your example you already use two UST/MSC values to estimate the current MSC. Allthough it is possible on some hardware to read the current sample position (MSC) it is not possible to the OS (or other hardware) to schedule on it and so you'll have to convert to another clock at some point. --martijn ------------------------------------------------------- This sf.net email is sponsored by: OSDN - Tired of that same old cell phone? Get a new here for FREE! https://www.inphonic.com/r.asp?r=sourceforge1&refcode1=vs3390 _______________________________________________ Alsa-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-devel
