[MPaulHolmes]

Edit: haha, here's a shorter version that does the same thing.
Here's the space vector part of the code:
Va, Vb, and Vc are the 3 phase voltages. pdc1, 2, and 3 are temp variables for the 3 duties. So, at the end you would do

PDC1 = pdc1;
PDC2 = pdc2;
PDC3 = pdc3;

void SpaceVectorModulation() { 
	// I know you can do it faster than this, but I just want it to work.  I'll optimize later.
	// if Vc is smallest of the 3, then do the following...
	if (Vc <= Va && Vc <= Vb) {  // Vc <= Vb <= Va or Vc <= Va <= Vb.  They both have the same
		// Q1 & Q2.
		pdc1 = Va-Vc;
		pdc2 = Vb-Vc;
		pdc3 = 0;
	}
	else if (Va <= Vc && Va <= Vb) { // Va is smallest
		// Q3 & Q4
		pdc1 = 0;
		pdc2 = Vb - Va;
		pdc3 = Vc - Va;
	}
	else if (Vb <= Va && Vb <= Vc) { // Vb is smallest
		// Q5 & Q6
		pdc1 = Va-Vb;
		pdc2 = 0;
		pdc3 = Vc-Vb;
	}	
}