Material scans: allow for cylindrical instead of spherical scans

benchmarks/others/materialScan.cxx

@@ -65,7 +65,7 @@ void materialScan(
     double rho = min(rmax * cos(theta), rhomax);
     double x = rho * cos(phi);
     double y = rho * sin(phi);
-    double z = (eta > 0? min(zpmax, rho * tan(theta)): max(-znmax, rho * tan(theta)));
+    double z = (eta > 0? min(zpmax, rho * sin(theta)): max(-znmax, rho * sin(theta)));
     std::cout << eta << ": " << x << ", " << y << ", " << z << std::endl;
     scan.emplace_back(gMaterialScan->scan(x0,y0,z0,x,y,z));
     total += scan.back().size();