docs: public synchronized void scaleTextSize(float scaleFactor, byte zoomLevel) {
          if (!textScales.containsKey(zoomLevel) || scaleFactor != textScales.get(zoomLevel)) {
              for (int i = 0, n = this.rulesList.size(); i < n; ++i) {
                  Rule rule = this.rulesList.get(i);
                  if (rule.zoomMin <= zoomLevel && rule.zoomMax >= zoomLevel) {
                      rule.scaleTextSize(scaleFactor * this.baseTextSize, zoomLevel);
                  }
              }
              textScales.put(zoomLevel, scaleFactor);
          }
      }