I'm trying to have an image follow my cursor, smoothly moving where it is located and turning to face it.
When i'm near the origin, it works flawlessy: the image will flip completely without issues, however the further i go from the origin of the window, the less the image turns. When i'm at the other side of the screen, instead of flipping over it'll rotate 5°-15° instead.
I'd love if somebody could point out what the issue is =)
Here's my current code for the image:
lblRover = new JLabel(sees) { // sees is an ImageIcon
protected void paintComponent(Graphics g) {
Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
AffineTransform aT = g2.getTransform();
Shape oldshape = g2.getClip();
double x = getWidth()/2.0;
double y = getHeight()/2.0;
aT.rotate(Math.toRadians(degrees), x, y);
g2.setTransform(aT);
g2.setClip(oldshape);
super.paintComponent(g);
}
};
lblRover.setSize(179, 180);
lblRover.setLocation(500, 300);
JFrame.getFrames()[0].add(lblRover);
And this is the code that handles the rotation, plus its movement:
NewJFrame.PInf = MouseInfo.getPointerInfo();
/* The frame is contained in NewJFrame, PInf is a PointerInfo */
p = (NewJFrame.PInf.getLocation()); // p is a point
p.x-=NewJFrame.getWindows()[0].getLocationOnScreen().x;
p.y-=NewJFrame.getWindows()[0].getLocationOnScreen().y;
//i subtract the location of the window relative to the screen
img = NewJFrame.lblRover.getLocation();
img.x+=NewJFrame.lblRover.getWidth()/2;
img.y+=NewJFrame.lblRover.getHeight()/2;
// img will be the point with the center of my image
sas=getAngle(p,img); // sas is a float variable
NewJFrame.degrees=sas;
//
// From now on i move the image
//
diffx = p.x-img.x;
diffy = p.y-img.y;
diffx/=80; // 80 is an arbitrary number to smooth the effect
diffy/=80; // high numbers will make the image not move at all
Point var = new Point(NewJFrame.lblRover.getLocation());
// I may have to use img here or subtract width and height /2
var.x+=diffx;
var.y+=diffy;
NewJFrame.lblRover.setLocation(var);
// A 5ms sleep to smooth the movement
// I also refresh a debug label
// Also i do refresh the frame, otherwise nothing happens
NewJFrame.jLabel1.setText(""+NewJFrame.lblRover.getLocation().y
+"/"+ p.y+" "+NewJFrame.lblRover.getLocation().x +"/"+ p.x );
NewJFrame.getFrames()[0].repaint();
try {
sleep(5);
} catch (InterruptedException ex) {
Logger.getLogger(thread.class.getName()).log(Level.SEVERE, null, ex);
}
Well, after multiple tries i've narrowed it down.
Now, the rotation code is put last, before the repaint, and it looks like this:
sas=this.getAngle((float)diffy,(float)diffx);
NewJFrame.degrees=sas;
I've also created this new method that uses two float instead of two points:
public float getAngle(Float x, Float y) {
float angle = (float) Math.toDegrees(Math.atan2(x, y));
//System.out.println(angle);
return angle;
I have no clue why it works now but it didn't before as the procedure is basically identical...but hey it works! =D