Initial Prey Game integration support.

neo/idlib/math/Vector.cpp

@@ -213,6 +213,42 @@ idMat3 idVec3::ToMat3( void ) const {
 	return mat;
 }
 
+#ifdef PREY
+// HUMANHEAD nla
+/*
+=============
+idVec3::hhToMat3
+=============
+*/
+idMat3 idVec3::hhToMat3(void) const {
+	idVec3	left;
+	idVec3	down;
+
+	// NormalVectors actually returns left and down
+	NormalVectors(left, down);
+	return idMat3(*this, left, -down);
+}
+
+// HUMANHEAD PDM: Vector conversion to/from axis aligned direction masks (6-bit vector compression)
+int idVec3::DirectionMask() const {
+	int mask = 0;
+	for (int term = 0; term < 3; term++) {
+		mask += (*this)[term] < 0 ? 1 << (term << 1) : (*this)[term]>0 ? 1 << ((term << 1) + 1) : 0;
+	}
+	return mask;
+}
+
+idVec3::idVec3(int directionMask) {
+	int negativeMask, positiveMask;
+	for (int term = 0; term < 3; term++) {
+		negativeMask = 1 << (term << 1);
+		positiveMask = 1 << ((term << 1) + 1);
+		(*this)[term] = (directionMask & negativeMask) ? -1 : (directionMask & positiveMask) ? 1 : 0;
+	}
+}
+// HUMANHEAD END
+#endif
+
 /*
 =============
 idVec3::ToString