我想绘制一个正多边形inscrit,并且我编写了一些代码,它们的公式通常为angle = 2 * Math.Pi / numside ecc ecc。
用圆环以灵巧的运动通过二维绘制的Poylgon:
public void Set_beahvior(Pane DrawPane, BottomPane bottompane )
{
this.selectedProperty().addListener(new ChangeListener<Boolean>()
{
private final EventHandler<MouseEvent> pressedHandler = (event) -> {
cerchio = new MyCircle(event.getX(), event.getY(), 0.0, DrawPane ,bottompane1);
cerchio.setCenterX(event.getX());
cerchio.setCenterY(event.getY());
cerchio.setStrokeType(StrokeType.OUTSIDE);
cerchio.setStroke(Color.RED);
cerchio.setFill(Color.TRANSPARENT);
cerchio.setStrokeWidth(1);
currentPolygon= new MyPolygon2(DrawPane,bottompane);
DrawPane.getChildren().addAll(cerchio);
DrawPane.getChildren().addAll(currentPolygon);
};
private final EventHandler<MouseEvent> draggedHandler = (event) -> {
cerchio.setRadius((event.getX()-cerchio.getCenterX()));
currentPolygon.setPolygon(cerchio.getCenterX(), cerchio.getCenterY(), cerchio.getRadius(),cerchio);
};
private final EventHandler<MouseEvent> releasedHandler = (event) -> {
cerchio.setRadius((event.getX()-cerchio.getCenterX()));
cerchio.setStroke(Color.TRANSPARENT);
};
@Override
public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) {
// add/remove event handlers based on toggle state of the button
if (newValue) {
DrawPane.addEventHandler(MouseEvent.MOUSE_PRESSED, pressedHandler);
DrawPane.addEventHandler(MouseEvent.MOUSE_DRAGGED, draggedHandler);
DrawPane.addEventHandler(MouseEvent.MOUSE_RELEASED, releasedHandler);
} else {
DrawPane.removeEventHandler(MouseEvent.MOUSE_PRESSED, pressedHandler);
DrawPane.removeEventHandler(MouseEvent.MOUSE_DRAGGED, draggedHandler);
DrawPane.removeEventHandler(MouseEvent.MOUSE_RELEASED, releasedHandler);
}
}
});
还有另一段代码:
public void setPolygon(Double x, Double y, Double radius, MyCircle circle){
DoubleProperty raggio = new SimpleDoubleProperty(circle.getRadius());
double section = 2.0 * Math.PI/Numside;
this.getPoints().addAll((x + raggio.doubleValue() * Math.cos(0)), (y + raggio.doubleValue() * Math.sin(0)));
for(int i=1; i<Numside; i++){
this.getPoints().addAll((x + raggio.doubleValue() * Math.cos(section * i)), (y + raggio.doubleValue() * Math.sin(section * i)));
}
}
问题:我从3面开始,然后我将写一些通用面的代码,但是如果我将圆的半径右增加(增加半径->三角形递增),一切都会很好。 />
但是如果我减小圆的半径,多边形就不会跟随圆的行为,而且我不明白为什么,会有任何建议吗?
PS:请忽略Doubleproperty和一些只为测试编写的代码,我知道如果我通过了圆对象,则不需要其他参数,此刻,我正在研究多边形的原因。不跟随圆周。
答案 0 :(得分:1)
您永远不会清除Polygon
中的任何要点。您需要确保points
列表中的坐标保持为边数的两倍。此外,setPolygon
的参数定义不正确:您通过前三个参数和最后一个参数传递了相同的信息;同样,您使用引用类型Double
的原因也不明显。以下代码对代码进行了一些改进:
private final int numside;
private final double[] points;
public MyPolygon2(int numside) {
this.numside = numside;
this.points = new double[numside * 2];
double step = 2 * Math.PI / numside;
for (int i = 0; i < numside; i++) {
int index = 2 * i;
double angle = i * step;
points[index] = Math.cos(angle);
points[index + 1] = Math.sin(angle);
}
}
public void setPolygon(double x, double y, double radius) {
getPoints().clear();
for (int i = 0; i < points.length;) {
getPoints().addAll(x + radius * points[i++], y + radius * points[i++]);
}
}