public override void DrawImage(BitmapData data_bac) { if (TIME < MID_TIME) data_bac.MergeGradient_RGB(DIRECTION, COLOR, MERGE_RATIO * TIME / MID_TIME, COVER_RATIO); else data_bac.MergeGradient_RGB(DIRECTION, COLOR, MERGE_RATIO * (PERIOD - TIME) / (PERIOD - MID_TIME), COVER_RATIO); }