Java Swing旋转和缩放

Question

我有一个被JScrollPane包围的JPanel。该JPanel用于显示图像。我需要提供zoomIn、zoomOut、顺时针旋转和逆时针旋转等功能。所有这些功能单独运行良好。对于缩放，我称之为图形对象的缩放。它发生在从左上到右下的基础上。对于旋转，我重置比例，然后平移、旋转

因此，问题是当面板坐标更改时，图像的坐标不会改变。有人可以帮助我更改图像的坐标吗？

public void paint(Graphics g)
{     
    Graphics2D g2d = (Graphics2D)g;
    g2d.translate((tempWidth/2), (tempHeight/2));
    g2d.rotate(m_rotate);
    g2d.translate(-(tempWidth/2), -(tempHeight/2));
    g2d.scale(m_zoom, m_zoom); 
    if(this.image != null && this.image.getHeight(null) > 0)
    {
        g2d.drawImage(this.image, 0, 0,302,312,this);         
    } 
    else
    {
        g2d.drawString("View Image Here!. ", 20, 20);
    }    
} 

Answer 1

谢谢你的帮助。它让我从一个新的角度思考，帮助我解决了这个问题。我所做的只是在旋转前缩放图像，现在运行良好。

public void paint(Graphics g) 
{          
    Graphics2D g2d = (Graphics2D)g; 
    g2d.scale(m_zoom, m_zoom);//This is what made the magic    
    g2d.translate((tempWidth/2), (tempHeight/2));     
    g2d.rotate(m_rotate);     
    g2d.translate(-(tempWidth/2), -(tempHeight/2)); 
    /*g2d.scale(m_zoom, m_zoom); removed this and placed above */
    if(this.image != null && this.image.getHeight(null) > 0)     
    {         
        g2d.drawImage(this.image, 0, 0,302,312,this);
    }
    else
    {         
        g2d.drawString("View Image Here!. ", 20, 20);
    }     
}