interpretor/preprocessor/faust-0.9.47mr3/documentation/faust-quick-reference-src/images/noise.dsp

   1 declare name            "Noise";
   2 declare version         "1.1";
   3 declare author          "Grame";
   4 declare license         "BSD";
   5 declare copyright       "(c)GRAME 2009";
   6
   7
   8 //-----------------------------------------------------------------
   9 // Noise generator and demo file for the Faust math documentation
  10 //-----------------------------------------------------------------
  11
  12
  13 <mdoc>
  14 \section{Presentation of the "noise.dsp" Faust program}
  15 This program describes a white noise generator with an interactive volume, using a random function.
  16
  17 \subsection{The random function}
  18 The \texttt{random} function describes a generator of random numbers, which equation follows. You should notice hereby the use of an integer arithmetic on 32 bits, relying on integer wrapping for big numbers.
  19 <equation>random</equation>
  20
  21 \subsection{The noise function}
  22 The white noise then corresponds to:
  23 <equation>noise</equation>
  24 </mdoc>
  25
  26 random  = +(12345)~*(1103515245);
  27 noise   = random/2147483647.0;
  28
  29 <mdoc>
  30 \subsection{Just add a user interface element to play volume!}
  31 Endly, the sound level of this program is controlled by a user slider, which gives the following equation:
  32 <equation>process</equation>
  33 </mdoc>
  34
  35 <mdoc>
  36 \section{Block-diagram schema of process}
  37 This process is illustrated on figure 1.
  38 <diagram>process</diagram>
  39 </mdoc>
  40
  41 process = noise * vslider("Volume[style:knob]", 0, 0, 1, 0.1);
  42
  43 <mdoc>
  44 \section{Notice of this documentation}
  45 You might be careful of certain information and naming conventions used in this documentation:
  46 <notice>
  47
  48 \section{Listing of the input code}
  49 The following listing shows the input Faust code, parsed to compile this mathematical documentation.
  50 <listing>
  51 </mdoc>