# Band Limited waveforms my way¶

• Author or source: Anton Savov (gb.liam@ottna)
• Type: classic Sawtooth example
• Created: 2009-06-22 18:09:08
notes
```This is my <ugly> C++ code for generating a single cycle of a Sawtooth in a table
normaly i create my "fundamental" table big enough to hold on around 20-40Hz in the
current Sampling rate
also, i create the table twice as big, i do "mip-maps" then
so the size should be a power of two, say 1024 for 44100Hz = 44100/1024 = ~43.066Hz
then the mip-maps are with decreasing sizes (twice) 512, 256, 128, 64, 32, 16, 8, 4, and 2

if the "gibbs" effect is what i think it is - then i have a simple solution
here is my crappy code:
```
code
 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35``` ```int sz = 1024; // the size of the table int i = 0; float *table; // pointer to the table double scale = 1.0; double pd; // phase double omega = 1.0 / (double)(sz); while (i < sz) { double amp = scale; double x = 0.0; // the sample double h = 1; // harmonic number (starts from 1) double dd; // fix high frequency "ring" pd = (double)(i) / (double)(sz); // calc phase double hpd = pd; // phase of the harmonic while (true) // start looping for this sample { if ((omega * h) < 0.5) // harmonic frequency is in range? { dd = cos(omega * h * 2 * pi); x = x + (amp * dd * sin(hpd * 2 * pi)); h = h + 1; hpd = pd * h; amp = 1.0 / h; } else { break; } } table[i] = x; ++i; } the peaks are around +/- 0.8 a square can be generated by just changing h = h+2; the peaks would be +/- 0.4 any bugs/improvements? ```

```excuse me, there is a typo

amp = scale / h;
```
• Date: 2009-09-20 10:34:18
• By: antto mail bg
```for even smoother edges:
dd = cos(sin(omega * h * pi) * 0.5 * pi);
no visual ringing, smooth waveform
```
• Date: 2009-09-25 04:15:31
• By: antto mail bg
```to get +/- 1.0 amplitude: scale = 1.25
```