The attached file is from Puckette's book Theory and Technique. I don't understand the lower part of the patch, from [*~ 128] downwards. Multiplying the Sequence and the Envelope gives peak values of +0.5 and -0.5. This is then multiplied by 128 and added 129, so the values range from 65 to 193. These values are index no for [tabread~ sample]. But the Sample wavetable size is 259. Shouldn't the index number range 0-258?
Puckette writes: "This is used to control the grain size." I don't understand what is grain size and maybe that's why I don't understand this patch. Could someone clarify?