Current waveform to 3 phase inverter driving BLDC motor

The following shows flat topped current pulses flowing to the 3 phase inverter from the DC link capacitor...
**broken link removed**


...why are they flat topped?, i would have thought that they would be rising in current , (ie trapezoidal shaped current pulses) since di = (V.dt)/L.
After all, if you put a voltage across an inductor, (in this case each motor phase inductance in turn), the current rises linearly

If you and I are looking at the same graph:

Maybe, for that particular example, they're limiting the V (starting at 1/3 of PW duration and thereby limiting the I), as suggested in the text, and did not include that waveform in the graph?