scale method
void
scale()
Implementation
void scale(int direction, int minFocal, int maxFocal, double minScale,
double maxScale, double threshold) {
if (appPlayerSetScale == null) return;
if (minScale < 1.0) minScale = 1.0;
if (maxScale < 1.0) maxScale = 1.0;
appPlayerSetScale(
playerId, minScale, maxScale, minFocal, maxFocal, direction, threshold);
}