AffineTransform似乎忽略了组件边界

Question

我有以下内容:

public class ParametricEQView extends JPanel implements PluginView {
    private static final int BAND_WIDTH = 3;
    private static final int THROW_HEIGHT = 64;

    private static final int WIDTH = 128*BAND_WIDTH + 2*MARGIN;
    private static final int HEIGHT = 2*THROW_HEIGHT + 2*MARGIN;
    private static final int MID_HEIGHT = THROW_HEIGHT + MARGIN;

    private final ParametricEQ _peq;

    public ParametricEQView(ParametricEQ peq) {
        super();
        _peq = peq;

        SwingUtils.freezeSize(this, WIDTH, HEIGHT);
        setToolTipText("Parametric Equalizer");
    }

    @Override
    public void paint(Graphics g) {
        final Graphics2D g2d = (Graphics2D) g;
        final int max = findMax();

        g.setColor(BACKGROUND);
        g.fillRect(0, 0, WIDTH, HEIGHT);

        g.setColor(DATA);
        final double scalingFactor = -((double) THROW_HEIGHT) / max;
        final double[] fineLevels = _peq.getFineLevels();
        int x = MARGIN;
        int h;
        final int[] xPoints = new int[128];
        final int[] yPoints = new int[128];
        for (int i = 0; i < 128; ++i) {
            h = (int) (fineLevels[i] * scalingFactor);
            xPoints[i] = x;
            yPoints[i] = MID_HEIGHT + h;
            x += BAND_WIDTH;
        }
        g.drawPolyline(xPoints, yPoints, 128);

        g.setColor(AXES);
        g.drawLine(MARGIN, MARGIN, MARGIN, HEIGHT-MARGIN);
        g.drawLine(MARGIN, MID_HEIGHT, WIDTH-MARGIN, MID_HEIGHT);

        g.setFont(AXIS_FONT);
        final FontMetrics metrics = g.getFontMetrics();
        int width = (int) metrics.getStringBounds(AXIS_LABEL_INPUT_MIDINUM, g).getWidth();
        g.drawString(AXIS_LABEL_INPUT_MIDINUM, WIDTH-MARGIN-width, HEIGHT-3);

        final AffineTransform atx = new AffineTransform();
        atx.setToRotation(-Math.PI/2, 0, HEIGHT);
        g2d.setTransform(atx);
        final String topLabel = "+" + max;
        width = (int) metrics.getStringBounds(topLabel, g).getWidth();
        g2d.drawString(topLabel, HEIGHT-MARGIN-width, HEIGHT+10);

        width = (int) metrics.getStringBounds(AXIS_LABEL_OUTPUT_VELOCITY, g).getWidth();
        g2d.drawString(AXIS_LABEL_OUTPUT_VELOCITY, MID_HEIGHT-(width/2), HEIGHT+10);

        g2d.drawString("-" + max, MARGIN, HEIGHT+10);
    }

    private int findMax() {
        int max = 3;
        for (int i = 0; i < 128; ++i)
            max = Math.max(max, (int) Math.ceil(Math.abs(_peq.getFineLevels()[i])));
        return max;
    }
}

这就是它的样子:
的ParametricEQView是与白色背景填充大部分的窗口的组件.在这个图像中,它的坐标是包含框架中的(0,0),一切都很棒.但是,如果我调整窗口的大小以使其ParametricEQView移动一点(它具有固定的大小并设置为在其可用空间中居中),则旋转的文本保持相对于框架的(0,0)而不是零件:

其他所有东西都是相对于面板绘制的,它只是旋转的文本而不是.我究竟做错了什么？

Answer 1

当您调用时，g2d.setTransform(atx);您将覆盖 Graphics 对象中当前设置的变换，即面板与其父框架之间的转换。这就是为什么文本是在框架参考中绘制的，而不是在面板参考中绘制的。

正确的代码是获取当前的变换并修改它或直接调用Graphics2D.rotate(double).