What am I misunderstanding about lookup~ ?


    Jan 23 2011 | 7:08 pm
    I'm trying to use lookup~ to create a mapping for a variable pseudo-doppler effect on a panner. It isn't working
    I'm having trouble pointing lookup~ to the correct area of the table I want to use - telling it the sample offset and the table size. I want the lookup to remain centered on the buffer - the buffer is 4410 samples long so I want it to centre on 2205.
    So I'm calculating offset based on the desired wavetable length - if I want wavetable length of 400, centred on the middle of the buffer then offset should be
    2205 -(400/2) = 2005, right?
    Doesn't seem to work.
    I'm feeding lookup~ with signal values from -1 to 1... so I think I got that right.
    I figure must be misunderstanding something quite fundamental. Any ideas?

    • Jan 23 2011 | 9:13 pm
      I just twigged - the "table length" is not actually table or anything to do with length at all - it's the end of the table, in samples. The documentation/labelling a bit misleading - might be worth clarifying in the next release?