RadialWipeTransition2D.java 文件源码

@Override
public Transition2DInstruction[] getInstructions(float progress,
        Dimension size) {

    int multiplier2 = -1;
    if(type==COUNTER_CLOCKWISE) 
        multiplier2 = 1;
    //for a good time, don't make multiplier1 = 0
    int multiplier1 = 0; //multiplier2;
    int k = Math.max(size.width,size.height);
    Area area = new Area(new Arc2D.Double(new Rectangle2D.Double(size.width/2-2*k,size.height/2-2*k,k*4,k*4),
            90+multiplier1*progress*360, multiplier2*progress*360,Arc2D.PIE));
    area.intersect(new Area(new Rectangle(0,0,size.width,size.height)));

    return new ImageInstruction[] {
            new ImageInstruction(true),
            new ImageInstruction(false, null, area)
    };
}