Develop Reference

RoundRectangle2D clip is not very smooth

I have a JPanel that i want to clip the corners so that it has rounded edge.
Here is what i am doing.
((Graphics2D)g).setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
g.setColor(color);
Shape s = new RoundRectangle2D.Double(0, 0, width, height, arc, arc);
g.setClip(s);
So notice that i am setting the clipping to a RoundRectangle2D. Also i am setting anti-aliasing still my rounded edges are really jagged.
Soft clipping example this link has a way to do soft rounded edges for a image. How do i apply the same to a JPanel?

because clipping is not aliased, you see the jagged edges. try a border instead:
p.setBorder(new RoundedBorder(p.getBackground(), 2, 16));
where RoundedBorder is adapted from the text bubble class:
class RoundedBorder extends AbstractBorder {
private Color color;
private int thickness = 4;
private int radii = 8;
private Insets insets = null;
private BasicStroke stroke = null;
private int strokePad;
private int pointerPad = 4;
RenderingHints hints;
RoundedBorder(
Color color, int thickness, int radii) {
this.thickness = thickness;
this.radii = radii;
this.color = color;
stroke = new BasicStroke(thickness);
strokePad = thickness / 2;
hints = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
int pad = radii + strokePad;
int bottomPad = pad + strokePad;
insets = new Insets(pad, pad, bottomPad, pad);
}
#Override
public Insets getBorderInsets(Component c) {
return insets;
}
#Override
public Insets getBorderInsets(Component c, Insets insets) {
return getBorderInsets(c);
}
#Override
public void paintBorder(
Component c,
Graphics g,
int x, int y,
int width, int height) {
Graphics2D g2 = (Graphics2D) g;
int bottomLineY = height - thickness;
RoundRectangle2D.Double bubble = new RoundRectangle2D.Double(
0 + strokePad,
0 + strokePad,
width - thickness,
bottomLineY,
radii,
radii);
Area area = new Area(bubble);
g2.setRenderingHints(hints);
Area spareSpace = new Area(new Rectangle(0, 0, width, height));
spareSpace.subtract(area);
g2.setClip(spareSpace);
g2.clearRect(0, 0, width, height);
g2.setClip(null);
g2.setColor(color);
g2.setStroke(stroke);
g2.draw(area);
}
}
}

If you want anti-aliased corners, use TexturePaint instead of clipping. It is the same as clipping, only faster. Use it with anti-alias on.
Just Google "TexturePaint examples".

Current Coordinate of bufferedImage Object in java

Is there anyway to find the current position of a buffered image on jpanel?
I draw an image on buffer, named it currentImage. Now I want to move it around a Panel by using affine transform.
To do translation by using mouse, I have to know the current position, new position and update the new position.
But I have trouble in getting the current position of the BufferedImage. There is no method in the IDE's suggestion working.
Can anyone give me an idea how to do this ?? Thanks!
EDIT
this is my draw and paintComponent method:
private void draw(){
AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC);
int w = this.getWidth(); int h = this.getHeight();
if (currentImage == null || width != w || height != h){
width = w;
height = h;
currentImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
graphics = currentImage.createGraphics();
graphics.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_GASP);
drawClearAndGradedArea(graphics);
drawActualRunway(graphics, width, height, width, height);
drawLeftToRight(graphics);
drawRightToLeft(graphics);
drawCentralLine(graphics);
graphics.setComposite(ac);
}
}
paintComponent()
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.clearRect(0,0, this.getWidth(), this.getHeight());
RenderingHints rh = new RenderingHints(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
g2d.setRenderingHints(rh);
g2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_GASP);
/*
* main components on panel
*/
this.draw();
this.animation();
g2d.drawImage(currentImage, transform, this);
drawNote(g2d);
g2d.dispose();
}

How to write text inside a rectangle

Hi I am creating a java desktop application where I am drawing rectangle. I want to write some text inside rectangle.
How can I achieve this?
Here is my code:
class DrawPanel extends JPanel {
private void doDrawing(Graphics g) {
int a=90;
int b=60;
int c=10;
int d=15;
ArrayList<Graphics2D> g1 = new ArrayList<Graphics2D>();
for(int i=0;i<=9;i++){
Graphics2D g2d = (Graphics2D) g;
g2d.setColor(new Color(212, 212, 212));
g2d.drawRect(c, d, a, b);
d+=65;
}
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
doDrawing(g);
}
}

Use your Graphics2D object and call drawString(String str, int x, int y). Something like
g2d.drawRect(c, d, a, b);
g2d.drawString("Hi", (a+c)/2, (b+d)/2);
Note that the Javadoc specifies
Draws the text given by the specified string, using this graphics context's current font and color. The baseline of the leftmost character is at position (x, y) in this graphics context's coordinate system.
so you would need to take into account the space the font takes on screen. Use FontMetrics for that.

Coloring the outside of a circle using arcAngle

Question about the circumference of circles. In order to change the outside color of the circle (circumference) I would use
drawArc(int x, int y, int width, int height, int startAngle, int arcAngle)
Just not exactly how to start off after the following code below..after Public void drawArc I dont know where to go
public void paintComponent(Graphics g) {
super.paintComponent(g);
Dimension d = getSize();
for(int i = 0; i < 100; ++i) {
Color color = new Color(generator.nextInt(255), generator.nextInt(255), generator.nextInt(255));
g.setColor(color);
int circleSize = generator.nextInt(d.width / 4);
int x = generator.nextInt(d.width - circleSize);
int y = generator.nextInt(d.height - circleSize);
g.fillOval(x, y, circleSize, circleSize);
g.drawArc(x, y, circleSize, circleSize, 0, 360);
}
}

You are drawing the body of a circle, then drawing its outline, without changing the colour in between. That means you can't actually see the outline of the circle.
I think you should change the colour of the graphics context, before you draw the outline. One way would be to insert
color = new Color(generator.nextInt(255), generator.nextInt(255), generator.nextInt(255));
g.setColor(color);
before the call to drawArc.

You don't need your own drawArc method, you should be calling the Graphics.drawArc() method. x and y are the center of the circle, width and height are the diameter of the circle, and startAngle and arcAngle are where to start and stop drawing the circle. 0 is 3 o'clock. So to draw a complete circle you would use 0 and 360 for startAngle and arcAngle.

Get position image after Rotation with AffineTransform

I use an AffineTransform class to transform my image and I need to have a position of image after translation and rotation. How to achieve that?
public void rotateImage(ImageObserver o, Graphics g, int x, int y) {
AffineTransform at = new AffineTransform();
at.translate(x, y);
at.rotate(Math.toRadians(deegres),ramie1.getWidth()/2,0);
Graphics2D g2 =(Graphics2D) g;
g2.drawImage(image, at, null);
}