- const double thr_lo = visual_y - thresholds[0] * scale_;
- const double thr_hi = visual_y - thresholds[1] * scale_;
+ int thr_lo = visual_y - thresholds[0] * scale_;
+ int thr_hi = visual_y - thresholds[1] * scale_;
+ thr_lo = min(max(thr_lo, top), btm);
+ thr_hi = min(max(thr_hi, top), btm);