自定义形状的旋转问题 [英] custom shape rotation issue
问题描述
我试图绕其中心的自定义形状，但预期不能得到结果。
I am trying to rotate a custom shape around its center, but can not get the result as expected.
我想是
*的形状应围绕其中心旋转不动，本身。的*
*shape should be rotated around its center without moving itself.*
目前，什么我的解决方案正在做的是
旋转围绕其中心的整体形状，由每转的改变其立场。
what my solution is currently doing is rotating a whole shape around its center , by every rotation its changing its position.
我有多个形状，所以我创建了一个类来封装的形状与它在下面的类变换
I have multiple shapes so i have created a class to encapsulate a shape with its transform in following class
public abstract class Shoe implements Shape, ShoeShape {
// variable declaration
/**
*
*/
public Shoe() {
position = new Point();
lastPosition = new Point();
}
public void draw(Graphics2D g2, AffineTransform transform, boolean firstTime) {
AffineTransform af = firstTime ? getInitTransform()
: getCompositeTransform();
if (af != null) {
Shape s = af.createTransformedShape(this);
if (getFillColor() != null) {
g2.setColor(getFillColor());
g2.fill(s);
} else {
g2.draw(s);
}
}
}
}
public AffineTransform getCompositeTransform() {
AffineTransform af = new AffineTransform();
af.setToIdentity();
af.translate(position.getX(), position.getY());
Point2D centerP = calculateShapeCenter();
af.rotate(orientation, centerP.getX(), centerP.getY());
return af;
}
public void onMouseDrag(MouseEvent me, Rectangle2D canvasBoundary,
int selectionOperation) {
// shape operation can be either resize , rotate , translate ,
switch (selectionOperation) {
case MmgShoeViewer.SHAPE_OPERATION_MOVE:
// MOVEMENT
break;
case MmgShoeViewer.SHAPE_OPERATION_ROTATE:
Point2D origin = calculateShapeCenter();
Point2D.Double starting = new Point2D.Double(me.getX(), me.getY());
currentAngle = RotationHelper.getAngle(origin, starting);
rotationAngle = currentAngle - startingAngle;
rotate(rotationAngle);
break;
case MmgShoeViewer.SHAPE_OPERATION_RESIZE:
break;
default:
System.out.println(" invalid select operation");
}
}
public void onMousePress(MouseEvent me, Rectangle2D canvasBoundary,
int selectionOperation) {
// shape operation can be either resize , rotate , translate ,
switch (selectionOperation) {
case MmgShoeViewer.SHAPE_OPERATION_MOVE:
break;
case MmgShoeViewer.SHAPE_OPERATION_ROTATE:
Point2D origin = calculateShapeCenter();
Point2D.Double starting = new Point2D.Double(me.getX(), me.getY());
startingAngle = RotationHelper.getAngle(origin, starting);
setShapeOperation(selectionOperation);
break;
case MmgShoeViewer.SHAPE_OPERATION_RESIZE:
break;
default:
System.out.println(" invalid select operation");
}
}
public void onMouseRelease(MouseEvent me, Rectangle2D canvasBoundary,
int selectionOperation) {
// shape operation can be either resize , rotate , translate ,
switch (selectionOperation) {
case MmgShoeViewer.SHAPE_OPERATION_MOVE:
break;
case MmgShoeViewer.SHAPE_OPERATION_ROTATE:
// FIXME rotation angle computation
setShapeOperation(-1);
break;
case MmgShoeViewer.SHAPE_OPERATION_RESIZE:
break;
default:
System.out.println(" invalid select operation");
}
}
public void rotate(double angle) {
orientation = (float) angle;
}
public void translate(double deltaX, double deltaY) {
position.setLocation(deltaX, deltaY);
lastPosition.setLocation(deltaX, deltaY);
}
// another getter and setter
我使用下面的方法计算旋转角度
I am calculating angle of rotation using following method
public static double getAngle(Point2D origin, Point2D other) {
double dy = other.getY() - origin.getY();
double dx = other.getX() - origin.getX();
double angle;
if (dx == 0) {// special case
angle = dy >= 0 ? Math.PI / 2 : -Math.PI / 2;
} else {
angle = Math.atan(dy / dx);
if (dx < 0) // hemisphere correction
angle += Math.PI;
}
// all between 0 and 2PI
if (angle < 0) // between -PI/2 and 0
angle += 2 * Math.PI;
return angle;
}
在画布上的鼠标监听鼠标preSS事件
in mouse press event of the canvas mouse listener
selectedShape.onMousePress(me, canvasBoundary, shoeViewer
.getShapeOperation());
我打电话所选形状的onMouse preSS法
i am just calling selected shape's onMousePress method
和画布的鼠标监听我的鼠标拖动的方法，我打电话所选形状的onMouseDrag方法，更新的旋转角度，你可以从第一类见
and in my mouse drag method of the canvas mouse listener , i am just calling the selected shape's onMouseDrag method which updates the rotation angle as you can see from the very first class
selectedShape.onMouseDrag(me, canvasBoundary, shoeViewer
.getShapeOperation());
，你可以看到各个形状的绘制方法，绘制按照目前的改造，我是来自调用的paintComponent像
and you can see the draw method of the individual shape , to draw the shape according to current transform , i am calling from paintComponent like
Iterator<Shoe> shoeIter = shoeShapeMap.values().iterator();
while (shoeIter.hasNext()) {
Shoe shoe = shoeIter.next();
shoe.draw(g2, firstTime);
}
在这里shoeShapeMap包含了所有的自定义形状的当前画布上。
where shoeShapeMap contains all of the custom shapes currently on the canvas.
是我在做什么，在计算角度或确定锚点的错误？我目前的解决方案旋转通过检查所有条件[90度等]，你可以在上面提到的方法请参阅形状360度。
is i am doing mistake in calculating angle or determining anchor point ? my current solution rotates shape 360 degree by checking all the conditions[90 degree etc.] as you can see in the above mentioned method.
我想要的形状应该围绕其中心旋转，而不调整其大小，位置？
在字也很难解释，所以请给我建议任何更好的方法来这里展示一下我想达到什么目的？
i want the shape should be rotated around its center without resizing its positions ? in the word it is difficult to explain , so please suggest me any better way to show here what i want to accomplish ?
我想我已经提到的所有有关这一问题的事情。如果您有任何疑问，请随时问我。
i think i have mentioned all the things related to this issue. if you have any doubts please feel free to ask me.
我发现这里2相关的帖子，但我无法从他们身上找到多少信息。
i found 2 related posts here but i could not find much information from them.
推荐答案
我认为解决方案可能是（或/和）：
I think that the solution may be to (either/and):
- 控制反转的AffineTransform操作的顺序，放旋转 翻译后
- 使用-x和-y您的翻译值
这篇关于自定义形状的旋转问题的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
