code: private static float polyMinExtent(float[] verts, int nverts) {
          float minDist = Float.MAX_VALUE;
          for (int i = 0; i < nverts; i++) {
              int ni = (i + 1) % nverts;
              int p1 = i * 3;
              int p2 = ni * 3;
              float maxEdgeDist = 0;
              for (int j = 0; j < nverts; j++) {
                  if (j == i || j == ni) {
                      continue;
                  }
                  float d = distancePtSeg2d(verts, j * 3, verts, p1, p2);
                  maxEdgeDist = Math.max(maxEdgeDist, d);
              }
              minDist = Math.min(minDist, maxEdgeDist);
          }
          return (float) Math.sqrt(minDist);
      }
docs: Calculate minimum extend of the polygon.