旋转Image对象

我有一个方法getImage()需要旋转一个Image ，将它存储在一个新的变量中，然后返回该新的Image 。 这是我的尝试，图像似乎是空的或什么的。 它只是没有出现在屏幕上：

 public Image getImage() { buffImage.createGraphics().rotate(direction); return buffImage; } 

当我拿出buffImage.createGraphics().rotate(direction); 图像在屏幕上绘制得很好，没有任何问题，但当然，没有旋转。

Answer 1

因此，基于此答案中的示例，您应该能够设计一种旋转方法，该方法可以将源图像旋转给定的度数，例如……

  // Make sure you actually load some image and assign it to this // variable, otherwise you will have a NullPointerException to // deal with private BufferedImage source; public Image rotateBy(double degrees) { // The size of the original image int w = source.getWidth(); int h = source.getHeight(); // The angel of the rotation in radians double rads = Math.toRadians(degrees); // Some nice math which demonstrates I have no idea what I'm talking about // Okay, this calculates the amount of space the image will need in // order not be clipped when it's rotated double sin = Math.abs(Math.sin(rads)); double cos = Math.abs(Math.cos(rads)); int newWidth = (int) Math.floor(w * cos + h * sin); int newHeight = (int) Math.floor(h * cos + w * sin); // A new image, into which the original can be painted BufferedImage rotated = new BufferedImage(newWidth, newHeight, BufferedImage.TYPE_INT_ARGB); Graphics2D g2d = rotated.createGraphics(); // The transformation which will be used to actually rotate the image // The translation, actually makes sure that the image is positioned onto // the viewable area of the image AffineTransform at = new AffineTransform(); at.translate((newWidth - w) / 2, (newHeight - h) / 2); // And we rotate about the center of the image... int x = w / 2; int y = h / 2; at.rotate(rads, x, y); g2d.setTransform(at); // And we paint the original image onto the new image g2d.drawImage(source, 0, 0, null); g2d.dispose(); return rotated; } 

Answer 2

您可以使用旋转图标并在JLabel显示Icon 。

Rotated Icon是一个可重用的类，因此您无需担心将旋转代码添加到需要此function的每个类。