4-in 4-out MSP external problem (SDK 5.1.1)

Hi there,

Both t_pxobject and t_pxbox contain a field called z_misc;
by default it is 0 meaning that all of the following settings are disabled:

#define Z_NO_INPLACE 1
#define Z_PUT_LAST 2
#define Z_PUT_FIRST 4

If you set the Z_NO_INPLACE bit in z_misc, the compiler will guarantee that all the signal vectors passed to your object will be unique. It is common that one or more of the output vectors your object will use in its perform method will be the same as one or more of its input vectors. Some objects are unable to handle this restriction; typically, this occurs when an object has pairs of inputs and outputs and writes an entire output on the basis of a single input before moving on to another input- output pair.

So in your specific case you have two options:

1 - Use the Z_NO_INPLACE flag, which you have to set in your new method
2- Change your perform loop to the following:

while (n--) {
    t_float sig1 = *in1++ * 0.1;
    t_float sig2 = *in2++ * 0.1;
    t_float sig3 = *in3++ * 0.1;
    t_float sig4 = *in4++ * 0.1;
    *out1++ = sig1;
    *out2++ = sig2;
    *out3++ = sig3;
    *out4++ = sig4;
}

Please, read the SDK docs and check out the MSP .h files. It is all in there...

Hope this helps you.

- Luigi