The ability to track and locate physical entities is a fundamental requirement for Cyber-Physical Systems (CPSs), especially in an ad-hoc wireless environment. In Heterogeneous Wireless Networks (HWNs), hybrid localization schemes are needed due to the coexistence of both accurate and coarse measurement mechanisms. However, current localization schemes cannot fully satisfy HWNs' accuracy requirements. Therefore, we propose a universal measurement metric called Direct Proportion Distance (DPD) that can leverage most existing measurement mechanisms such as TOA/TDOA, RSS, AOA, Link Diagnosis (LD) and Signal Coverage Detection (SCD). We also prove that DPD is directly proportional to the physical distance between two wireless nodes. Based on this metric, we present three new localization algorithms and compare them with classical methods. The experiments verify that our method performs better than previous localization algorithms when both accurate and coarse measurements are fully utilized.