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move dot between 2 points jframe [closed]

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Okay so I'm trying to replicate this in a jframe.
https://codepen.io/allanpope/pen/LVWYYd
Problem:
I have a loading screen and over the course of 5 seconds I'm moving dots from a circle to an image. Just like the codepen. Except the problem is I'm not sure how to animate it correctly. JAVA
My Idea was to make an animate function like Move.to(Dot,Duration)
One problem I'm having is that when using decimals the dots wont be in the exact place, and some wont move at all. I'm just not sure how to make this animate function and how to end it. If anyone could help me that would be epic. My code is down below. And if someone could tell me how I could do a Bezier curve animation would also be cool
If anyone wantes to test my code and tell me whats wrong that would be epic.
So first I have a function to make the circle positions
package loadingScreen;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.imageio.ImageIO;
public class LoadTree {
static BufferedImage tree;
static int radius =300;
public static List<Dot> dots = new ArrayList<Dot>();
public static void make() {
File e = new File("assets/tree.png");
try {
tree = ImageIO.read(e);
} catch (IOException e1) {
e1.printStackTrace();
}
for(int x = 0; x<tree.getWidth();x+=1) {
for(int y = 0; y<tree.getWidth();y+=1) {
int clr = tree.getRGB(x, y);
if(clr==0) {
}else {
int i =(y)*300+x;
int a = (i / 4) % 300;
int b = (int) Math.floor(Math.floor(i / 300) / 4);
if (( a % ((1)) == 0) && (b % ((1)) == 0)) {
double p = (double) Math.random();
int circleX = (int) (MyFrame.width/2+ radius * Math.cos(2 * Math.PI * p));
int circleY = (int) (MyFrame.height/2 + radius * Math.sin(2 * Math.PI * p));
Dot dot = new Dot(circleX, circleY, clr,
MyFrame.width/2+x-150, MyFrame.height/2+y-150,circleX,circleY);
dots.add(dot);
}
}
}
}
}
}
Here is the dot class
package loadingScreen;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
public class Dot {
public int imageY;
public int imageX;
public int color;
public double y;
public double x;
public int circleX;
public int circleY;
public Dot(int x, int y, int color, int imageX, int imageY, int circleX, int circleY){
this.x = x;
this.y = y;
this.color = color;
this.imageX = imageX;
this.imageY = imageY;
this.circleX = circleX;
this.circleY = circleY;
}
public void paint(Graphics g){
Graphics2D g2d = (Graphics2D)g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
Color c = new Color(color);
g2d.setColor(c);
g2d.fillRect((int)x,(int) y, 1, 1);
}
}
Here is the Jpanel
package loadingScreen;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JPanel;
import javax.swing.Timer;
import loadingScreen.animate.Move;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.URL;
public class MyPanel extends JPanel implements ActionListener{
Image background;
Timer timer;
MyPanel(){
timer = new Timer(0,this);
timer.start();
File e = new File("assets/background.png");
try {
background = ImageIO.read(e);
} catch (IOException e1) {
e1.printStackTrace();
}
}
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
//g2d.drawImage(background, 0, 0, MyFrame.width,MyFrame.height,null);
LoadTree.dots.forEach(dot ->{
dot.paint(g);
});
}
#Override
public void actionPerformed(ActionEvent e) {
LoadTree.dots.forEach(dot ->{
Move.to(dot, 1000, 0);
//get slope
});
repaint();
//System.out.println(LoadTree.dots.size());
}
}
And here is the Jframe
package loadingScreen;
import javax.swing.JFrame;
public class MyFrame extends JFrame{
MyPanel panel;
public static int width = 1080;
public static int height = 720;
MyFrame(){
panel = new MyPanel();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.add(panel);
this.setSize(width, height);
this.setLocationRelativeTo(null);
this.setVisible(true);
}
}

You are in for a massive deep dive. Animation, good animation, animation you don't notice, is really, really hard to achieve and is a very complex subject.
You've kind of started in the right direction. You need some kind of "ticker" to tell you when the animation should update, but it kind of falls apart after that.
The first thing you want to do is move away from the concept of "linear progression". That is, on each "tick", the object is moved by a specific delta value. This doesn't produce good animation and can fall apart really quickly when you want to change the speed or duration of the animation.
A better solution is to start with a "duration based progress". This is, basically, the animation will run over a fixed period of time and on each tick of the animation, you calculate the new "state" of the object based on the amount of time which has passed and the amount of time remaining.
This has the benefit of "normalising" the timeline. That is, the animation occurs between 0-1. From this it becomes incredibly easy to calculate where a object should be along that time line. Want to make it faster or slower? Change the duration, the rest is taken care for you!
To start with, figure out how to move one dot from one point to another, if you can move one, you can move a thousand.
Duration base animation engine...
Play close attention to:
The Utilities class
The DurationAnimationEngine
The engine is backed by a Swing Timer, so it's safe to use within Swing. It's whole purpose to run (as fast as it safely can) for a specified period of time and produce "ticks" with the amount of progression has occurred (remember, normalised time)
The following is basic implementation of the animation. A lot of the "work" happens in the mouseClicked event, as it starts the engine. When the engine ticks the dots are updated. Each dot is wrapped in AnimatableDot which has a "from" and "to" point, it then, based on the normalised time, calculates it's new position and then a paint pass is executed
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Point2D;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class DurationTest {
public static void main(String[] args) {
new DurationTest();
}
public DurationTest() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class Utilities {
public static Point2D pointOnCircle(double degress, double radius) {
double rads = Math.toRadians(degress - 90); // 0 becomes the top
double xPosy = Math.round((Math.cos(rads) * radius));
double yPosy = Math.round((Math.sin(rads) * radius));
return new Point2D.Double(radius + xPosy, radius + yPosy);
}
public static Point2D pointOnCircle(double xOffset, double yOffset, double degress, double radius) {
Point2D poc = pointOnCircle(degress, radius);
return new Point2D.Double(xOffset + poc.getX(), yOffset + poc.getY());
}
}
public class TestPane extends JPanel {
private List<AnimatedDot> dots = new ArrayList<>(128);
private Duration duration = Duration.ofSeconds(5);
private DurationAnimationEngine engine;
private List<Color> colors = Arrays.asList(new Color[]{
Color.RED,
Color.BLUE,
Color.CYAN,
Color.GRAY,
Color.GREEN,
Color.LIGHT_GRAY,
Color.MAGENTA,
Color.PINK,
Color.WHITE,
Color.YELLOW
});
public TestPane() {
Random rnd = new Random();
setBackground(Color.BLACK);
for (int index = 0; index < 100; index++) {
double fromAngle = 360.0 * rnd.nextDouble();
double toAngle = fromAngle + 180.0;
Collections.shuffle(colors);
Color color = colors.get(0);
dots.add(new AnimatedDot(
Utilities.pointOnCircle(fromAngle, 150),
Utilities.pointOnCircle(toAngle, 150),
color, 2));
}
addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
if (engine != null) {
engine.stop();
engine = null;
// Reset poisitions
for (AnimatedDot dot : dots) {
dot.move(0);
}
repaint();
return;
}
engine = new DurationAnimationEngine(duration, new DurationAnimationEngine.Tickable() {
#Override
public void animationDidTick(double progress) {
for (AnimatedDot dot : dots) {
dot.move(progress);
}
repaint();
}
});
engine.start();
}
});
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.setRenderingHint(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON
);
int xOffset = (getWidth() - 300) / 2;
int yOffset = (getWidth() - 300) / 2;
g2d.translate(xOffset, yOffset);
g2d.setColor(Color.DARK_GRAY);
g2d.drawOval(0, 0, 300, 300);
for (AnimatedDot dot : dots) {
dot.paint(g2d);
}
g2d.dispose();
}
}
public class DurationAnimationEngine {
public interface Tickable {
public void animationDidTick(double progress);
}
private Duration duration;
private Instant timeStarted;
private Timer timer;
private Tickable tickable;
public DurationAnimationEngine(Duration duration, Tickable tickable) {
this.duration = duration;
this.tickable = tickable;
}
public void start() {
// You could create the timer lazierly and restarted it as needed
if (timer != null) {
return;
}
timer = new Timer(5, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (timeStarted == null) {
timeStarted = Instant.now();
}
Duration runtime = Duration.between(timeStarted, Instant.now());
double progress = Math.min(1.0, runtime.toMillis() / (double) duration.toMillis());
tickable.animationDidTick(progress);
if (progress >= 1.0) {
stop();
}
}
});
timer.start();
}
public void stop() {
if (timer == null) {
return;
}
timer.stop();
timer = null;
}
}
public class AnimatedDot {
private Dot dot;
private Point2D from;
private Point2D to;
public AnimatedDot(Point2D from, Point2D to, Color color, int radius) {
dot = new Dot(from.getX(), from.getY(), color, radius);
this.from = from;
this.to = to;
}
public void paint(Graphics2D g) {
dot.paint(g);
}
public void move(double progress) {
Point2D pointAt = pointAt(progress);
dot.setLocation(pointAt);
}
public Point2D getFrom() {
return from;
}
public Point2D getTo() {
return to;
}
protected double getFromX() {
return getFrom().getX();
}
protected double getFromY() {
return getFrom().getY();
}
public Double getXDistance() {
return getTo().getX() - getFrom().getX();
}
public Double getYDistance() {
return getTo().getY() - getFrom().getY();
}
protected Point2D pointAt(double progress) {
double xDistance = getXDistance();
double yDistance = getYDistance();
double xValue = Math.round(xDistance * progress);
double yValue = Math.round(yDistance * progress);
xValue += getFromX();
yValue += getFromY();
return new Point2D.Double(xValue, yValue);
}
}
public class Dot {
private Color color;
private double y;
private double x;
private int radius;
private Ellipse2D dot;
public Dot(double x, double y, Color color, int radius) {
this.x = x;
this.y = y;
this.color = color;
this.radius = radius;
dot = new Ellipse2D.Double(0, 0, radius * 2, radius * 2);
}
public void setLocation(Point2D point) {
setLocation(point.getX(), point.getY());
}
public void setLocation(double x, double y) {
this.x = x;
this.y = y;
}
public void paint(Graphics2D g) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(color);
g2d.translate(x - radius, y - radius);
g2d.fill(dot);
g2d.dispose();
}
}
}
Okay, so when we run it, we get...
😮 ... Hmmm, I'd like to say that that was expected, but once I saw it, it was obvious what had gone wrong.
All the dots are moving at the same speed over the same time range!
So, what's the answer. Well, actually a few...
We could change the duration of each dot so that they have an individual duration. This would "randomise" the movement, but I'm not sure it would generate the exact same effect, as they'd be moving at different speeds
We could randomise the start time of the dots, so they started at different times, allowing them all to have the same duration (or even a randomised duration)
We could move only a small subset of the dots, but this would mean that you'd probably end up waiting for the current subset to finish before the next one started
A combination of 2 & 3
Individualised, randomised duration...
Okay, for simplicity (and my sanity), I'm actually going to start with 1. Each dot will have it's own, randomised duration. This means that each dot will be moving at a different speed though.
Pay close attention to LinearAnimationEngine and the AnimatedDot#move method.
This should look familiar, it's basically the same animation logic as before, just isolated for the dot itself
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Point2D;
import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class RandomIndividualDuration {
public static void main(String[] args) {
new RandomIndividualDuration();
}
public RandomIndividualDuration() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class Utilities {
public static Point2D pointOnCircle(double degress, double radius) {
double rads = Math.toRadians(degress - 90); // 0 becomes the top
double xPosy = Math.round((Math.cos(rads) * radius));
double yPosy = Math.round((Math.sin(rads) * radius));
return new Point2D.Double(radius + xPosy, radius + yPosy);
}
public static Point2D pointOnCircle(double xOffset, double yOffset, double degress, double radius) {
Point2D poc = pointOnCircle(degress, radius);
return new Point2D.Double(xOffset + poc.getX(), yOffset + poc.getY());
}
}
public class DurationRange {
private Duration from;
private Duration to;
public DurationRange(Duration from, Duration to) {
this.from = from;
this.to = to;
}
public Duration getFrom() {
return from;
}
public Duration getTo() {
return to;
}
public Duration getDistance() {
return Duration.ofNanos(getTo().toNanos() - getFrom().toNanos());
}
public Duration valueAt(double progress) {
Duration distance = getDistance();
long value = (long) Math.round((double) distance.toNanos() * progress);
value += getFrom().getNano();
return Duration.ofNanos(value);
}
}
public class TestPane extends JPanel {
private List<AnimatedDot> dots = new ArrayList<>(128);
private Duration duration = Duration.ofSeconds(5);
private LinearAnimationEngine engine;
private List<Color> colors = Arrays.asList(new Color[]{
Color.RED,
Color.BLUE,
Color.CYAN,
Color.GRAY,
Color.GREEN,
Color.LIGHT_GRAY,
Color.MAGENTA,
Color.PINK,
Color.WHITE,
Color.YELLOW
});
public TestPane() {
Random rnd = new Random();
setBackground(Color.BLACK);
DurationRange range = new DurationRange(Duration.ofSeconds(1), Duration.ofSeconds(5));
for (int index = 0; index < 100; index++) {
double fromAngle = 360.0 * rnd.nextDouble();
double toAngle = fromAngle + 180.0;
Collections.shuffle(colors);
Color color = colors.get(0);
Duration duration = range.valueAt(rnd.nextDouble());
dots.add(new AnimatedDot(
Utilities.pointOnCircle(fromAngle, 150),
Utilities.pointOnCircle(toAngle, 150),
color, 2, duration));
}
addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
if (engine != null) {
engine.stop();
engine = null;
reset();
return;
}
System.out.println("Go");
List<AnimatedDot> avaliableDots = new ArrayList<>(120);
avaliableDots.addAll(dots);
engine = new LinearAnimationEngine(new LinearAnimationEngine.Tickable() {
#Override
public void animationDidTick() {
List<AnimatedDot> completed = new ArrayList<>(128);
// Reset poisitions
for (AnimatedDot dot : avaliableDots) {
if (!dot.move()) {
completed.add(dot);
}
}
avaliableDots.removeAll(completed);
repaint();
if (avaliableDots.isEmpty()) {
engine.stop();
engine = null;
reset();
}
}
});
engine.start();
}
});
}
protected void reset() {
for (AnimatedDot dot : dots) {
dot.reset();
}
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.setRenderingHint(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON
);
int xOffset = (getWidth() - 300) / 2;
int yOffset = (getWidth() - 300) / 2;
g2d.translate(xOffset, yOffset);
g2d.setColor(Color.DARK_GRAY);
g2d.drawOval(0, 0, 300, 300);
for (AnimatedDot dot : dots) {
dot.paint(g2d);
}
g2d.dispose();
}
}
public class LinearAnimationEngine {
public interface Tickable {
public void animationDidTick();
}
private Tickable tickable;
private Timer timer;
public LinearAnimationEngine(Tickable tickable) {
this.tickable = tickable;
}
public void start() {
// You could create the timer lazierly and restarted it as needed
if (timer != null) {
return;
}
timer = new Timer(5, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
tickable.animationDidTick();
}
});
timer.start();
}
public void stop() {
if (timer == null) {
return;
}
timer.stop();
timer = null;
}
}
public class AnimatedDot {
private Dot dot;
private Point2D from;
private Point2D to;
private Duration duration;
private Instant timeStarted;
public AnimatedDot(Point2D from, Point2D to, Color color, int radius, Duration duration) {
dot = new Dot(from.getX(), from.getY(), color, radius);
this.from = from;
this.to = to;
this.duration = duration;
}
public void paint(Graphics2D g) {
dot.paint(g);
}
public void reset() {
Point2D futureFrom = to;
to = from;
from = futureFrom;
timeStarted = null;
}
public boolean move() {
if (timeStarted == null) {
timeStarted = Instant.now();
}
Duration runtime = Duration.between(timeStarted, Instant.now());
double progress = Math.min(1.0, runtime.toMillis() / (double) duration.toMillis());
Point2D pointAt = pointAt(progress);
dot.setLocation(pointAt);
return progress < 1.0;
}
public Point2D getFrom() {
return from;
}
public Point2D getTo() {
return to;
}
protected double getFromX() {
return getFrom().getX();
}
protected double getFromY() {
return getFrom().getY();
}
public Double getXDistance() {
return getTo().getX() - getFrom().getX();
}
public Double getYDistance() {
return getTo().getY() - getFrom().getY();
}
protected Point2D pointAt(double progress) {
double xDistance = getXDistance();
double yDistance = getYDistance();
double xValue = Math.round(xDistance * progress);
double yValue = Math.round(yDistance * progress);
xValue += getFromX();
yValue += getFromY();
return new Point2D.Double(xValue, yValue);
}
}
public class Dot {
private Color color;
private double y;
private double x;
private int radius;
private Ellipse2D dot;
public Dot(double x, double y, Color color, int radius) {
this.x = x;
this.y = y;
this.color = color;
this.radius = radius;
dot = new Ellipse2D.Double(0, 0, radius * 2, radius * 2);
}
public void setLocation(Point2D point) {
setLocation(point.getX(), point.getY());
}
public void setLocation(double x, double y) {
this.x = x;
this.y = y;
}
public void paint(Graphics2D g) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(color);
g2d.translate(x - radius, y - radius);
g2d.fill(dot);
g2d.dispose();
}
}
}
Now, when we run it we get...
Well, at least it's now more "randomised", and this is where I think points 2 & 3 might be a better mix.
But they're not rebounding?!
Ah, well, actually, click the second example again! The dots will move from the current position (the original to point) and back to their original from point. Soooo, conceptually, it's doable.
But they don't from a nice picture when I click it!
😐 ... So the above examples demonstrate how to animate a object from point A to point B over a specified duration, forming the picture is just changing the target destination (assuming you know what it was to start with). Based on my observations, a moving dot is first allowed to move to its current "end" position before moving to the final picture position, as trying to calculate a curving path would make me 🤯.
What's missing...
Yes, there's something missing, you probably can't see it, but it really stands out for me.
Each dot starts out slowly, speeds up and then decelerates into position. This is known as "easement" (or, in this case, ease-in/ease-out) and it's not the simplest thing in the world to implement. If you're really interested, take a look at How can I implement easing functions with a thread
Now, what is the actual answer to your question? Unless you're completely crazy (and I am), don't try to roll this kind of thing yourself, unless you have a very specific reason for doing so. Instead, make use one of the other ready made engines, for example:
universal-tween-engine
timingframework
Much of the concepts used above are taken from my animation playground source, Super Simple Swing Animation Framework. This is where I do a lot of my playing around and experimentation
This is one of those questions that has you digging deeper and trying to figure out what you could actually achieve, to that end BounceImagePixel is an accumulation of much tinkering to see "where this could go"

Determine if a shape is above another shape

I'm attempting to determine if one four sided shape is above another one, and returning the ratio of the amount that is uncovered. My definition of "uncovered" is if there is no other shape above the one being examined on the y-axis, and if there is how much they are intersecting on the x-axis.
Example:
In the above image, the desired output should be 0.6363. Out of the 110 pixels, 70 are intersecting with the object above it, and 70/110=0.6363
Another Example:
In this example the desired output would be 0.3636.
What I have attempted so far is that I am starting with double out = 1; and then if the y-axis of shape 2 is less than shape 1, I subtract the amount the two shapes intersect on the x axis from the ratio with some variant of out-=(c.getX2()-b.getX2())/Math.abs(c.getX1()-c.getX2());
However, this doesn't seem to be working, and my attempts at correcting the code seem to just be adding more and more unnecessary complexity. I assume there is a much easier way to do what I'm trying to do, but I'm not great with geometry.
c is the current shape being examined, and b is the one it is being compared to.
if(((b.getX2() < c.getX2()) && (b.getX2()>c.getX1()))||((b.getX2()>c.getX2())&&(b.getX2()<c.getX1()))||((b.getX1()>c.getX2())&&(b.getX1()<c.getX1()))) {
if(b.getY2() < c.getY2()) {
if((b.getX2() < c.getX2()) && (b.getX2()>c.getX1())) {
out-= (c.getX2()-b.getX2())/Math.abs(c.getX1()-c.getX2());
}
if(((b.getX2()>c.getX2())&&(b.getX2()<c.getX1()))) {
out-=(b.getX2()-c.getX2())/Math.abs(c.getX1()-c.getX2());
}
if(((b.getX1()>c.getX2())&&(b.getX1()<c.getX1()))) {
out-=(c.getX2()-b.getX2())/Math.abs(c.getX1()-c.getX2());
}
}
}

I think your approach is way to complicated, and you might just have got lost in all the different possible conditions and configurations.
If I understood you correctly, then the simplest solution would be to base the computations on the minimum and maximum X-values of both shapes.
Side note:
You did not say what type your "shape" objects b and c are. From the methods that you are calling, they might be a java.awt.geom.Line2D objects, but these are not really "four sided". In any case, you can compute the minimum and maximum values as
double bMinX = Math.min(b.getX1(), b.getX2());
double bMaxX = Math.max(b.getX1(), b.getX2());
double cMinX = Math.min(c.getX1(), c.getX2());
double cMaxX = Math.max(c.getX1(), c.getX2());
In the program below, I'm using actual Shape objects and call the getBounds2D method to obtain the bounding boxes, which offer these min/max values conveniently. But you can also do this manually.
When you have these minimum/maxmimum values, you can rule out the cases where an object is either entirely left or entirely right of the other object. If this is not the case, they are overlapping. In this case, you can compute the minimum and maximum of the overlap, and then divide this by the width of the object in question.
Here is a program where a example objects are created based on the coordinates you gave in the question. You can drag around the objects with the mouse. The overlap is painted and its value is printed.
The computation takes place in the computeOverlap method.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.Path2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class ShapeOverlap
{
public static void main(String[] args) throws IOException
{
SwingUtilities.invokeLater(() -> createAndShowGUI());
}
private static void createAndShowGUI()
{
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.getContentPane().add(new ShapeOverlapPanel());
f.setSize(900,500);
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}
class ShapeOverlapPanel extends JPanel
implements MouseListener, MouseMotionListener
{
private final List<Point2D> points0;
private final List<Point2D> points1;
private final List<Point2D> draggedPoints;
private Point previousMousePosition;
ShapeOverlapPanel()
{
points0 = new ArrayList<Point2D>();
points0.add(new Point2D.Double(160, 200));
points0.add(new Point2D.Double(180, 200));
points0.add(new Point2D.Double(270, 260));
points0.add(new Point2D.Double(250, 260));
points1 = new ArrayList<Point2D>();
points1.add(new Point2D.Double(200, 280));
points1.add(new Point2D.Double(220, 280));
points1.add(new Point2D.Double(310, 340));
points1.add(new Point2D.Double(290, 340));
draggedPoints = new ArrayList<Point2D>();
addMouseListener(this);
addMouseMotionListener(this);
}
#Override
protected void paintComponent(Graphics gr)
{
super.paintComponent(gr);
Graphics2D g = (Graphics2D)gr;
g.setRenderingHint(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g.setColor(Color.WHITE);
g.fillRect(0, 0, getWidth(), getHeight());
Shape s0 = createShape(points0);
Shape s1 = createShape(points1);
g.setColor(Color.RED);
g.fill(s0);
g.setColor(Color.BLUE);
g.fill(s1);
g.setColor(Color.GRAY);
drawOverlap(g, s0, s1);
double overlap = computeOverlap(s0, s1);
g.drawString("Overlap of red from blue: "+overlap, 10, 20);
}
private static double computeOverlap(Shape s0, Shape s1)
{
Rectangle2D b0 = s0.getBounds2D();
Rectangle2D b1 = s1.getBounds2D();
if (b0.getMaxX() < b1.getMinX())
{
System.out.println("Shape 0 is left of shape 1");
return Double.NaN;
}
if (b0.getMinX() > b1.getMaxX())
{
System.out.println("Shape 0 is right of shape 1");
return Double.NaN;
}
double overlapMinX = Math.max(b0.getMinX(), b1.getMinX());
double overlapMaxX = Math.min(b0.getMaxX(), b1.getMaxX());
double overlapSize = overlapMaxX - overlapMinX;
double relativeOverlap = overlapSize / b0.getWidth();
return relativeOverlap;
}
private void drawOverlap(Graphics2D g, Shape s0, Shape s1)
{
Rectangle2D b0 = s0.getBounds2D();
Rectangle2D b1 = s1.getBounds2D();
if (b0.getMaxX() < b1.getMinX())
{
return;
}
if (b0.getMinX() > b1.getMaxX())
{
return;
}
double overlapMinX = Math.max(b0.getMinX(), b1.getMinX());
double overlapMaxX = Math.min(b0.getMaxX(), b1.getMaxX());
g.drawLine((int)overlapMinX, 0, (int)overlapMinX, getHeight());
g.drawLine((int)overlapMaxX, 0, (int)overlapMaxX, getHeight());
}
private static Shape createShape(Iterable<? extends Point2D> points)
{
Path2D path = new Path2D.Double();
boolean first = true;
for (Point2D p : points)
{
if (first)
{
path.moveTo(p.getX(), p.getY());
first = false;
}
else
{
path.lineTo(p.getX(), p.getY());
}
}
path.closePath();
return path;
}
#Override
public void mouseDragged(MouseEvent e)
{
int dx = e.getX() - previousMousePosition.x;
int dy = e.getY() - previousMousePosition.y;
for (Point2D p : draggedPoints)
{
p.setLocation(p.getX() + dx, p.getY() + dy);
}
repaint();
previousMousePosition = e.getPoint();
}
#Override
public void mouseMoved(MouseEvent e)
{
}
#Override
public void mouseClicked(MouseEvent e)
{
}
#Override
public void mousePressed(MouseEvent e)
{
draggedPoints.clear();
Shape s0 = createShape(points0);
Shape s1 = createShape(points1);
if (s0.contains(e.getPoint()))
{
draggedPoints.addAll(points0);
}
else if (s1.contains(e.getPoint()))
{
draggedPoints.addAll(points1);
}
previousMousePosition = e.getPoint();
}
#Override
public void mouseReleased(MouseEvent e)
{
draggedPoints.clear();
}
#Override
public void mouseEntered(MouseEvent e)
{
}
#Override
public void mouseExited(MouseEvent e)
{
}
}

Adding an image to frame, not in center, but should be.. + game programming in general

I just started learning game programming, after taking a 1 semester course in the university, so i think im ready and i really want to do this, so first of all:
1) What could be good resources for learning? Ive googlef a lot and have two books: Killer Game Programming in Java and Begining java SE6 game programing. One is overly specific and not specific at the same time, the other explains very little, so its difficult understanding what is what. Esspecialy with rendering, the buffers, how to render to applets, frames and panels. Any help would be greatly appriciated ;) Thank you!
Ive writen a very basic code, to move a box around, everything is well, but the box isnt in the middle as it should be:
The object:
package milk;
public class Thing
{
double x,y;
Shape shape;
int[] thingx={-5,5,5,-5};
int[] thingy={5,5,-5,-5};
Thing(double x, double y)
{
setX(x);
setY(y);
setShape();
}
public void setX(double x)
{
this.x=x;
}
public void setY(double y)
{
this.y=y;
}
public void setShape()
{
this.shape=new Polygon(thingx,thingy,thingx.length);
}
public double getX()
{
return x;
}
public double getY()
{
return y;
}
public Shape getShape()
{
return shape;
}
public void incX(int i)
{
this.x+=i;
}
public void incY(int i)
{
this.y+=i;
}
}
The panel:
package milk;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.geom.AffineTransform;
import javax.swing.JPanel;
#SuppressWarnings("serial")
public class MilkPanel extends JPanel implements Runnable, KeyListener{
Thread animator;
Graphics2D g2d;
Thing thing=new Thing(320,240);
AffineTransform identity = new AffineTransform();
MilkPanel()
{
setSize(640,480);
setBackground(Color.black);
setFocusable(true);
requestFocus();
addKeyListener(this);
}
public void addNotify()
{
super.addNotify();
animator = new Thread(this);
animator.start();
}
public void paint(Graphics g)
{
g2d=(Graphics2D)g;
g2d.setColor(Color.black);
g2d.fillRect(0, 0, getSize().width,getSize().height);
drawThing();
g.dispose();
}
public void drawThing()
{
g2d.setTransform(identity);
g2d.translate(thing.getX(), thing.getY());
g2d.setColor(Color.orange);
g2d.draw(thing.getShape());
}
public void run()
{
while(true)
{
try
{
Thread.sleep(20);
}
catch(Exception e)
{
}
repaint();
}
}
public void keyPressed(KeyEvent e)
{
int key=e.getKeyCode();
switch(key)
{
case KeyEvent.VK_UP:
thing.incY(-5);
break;
case KeyEvent.VK_DOWN:
thing.incY(5);
break;
case KeyEvent.VK_RIGHT:
thing.incX(5);
break;
case KeyEvent.VK_LEFT:
thing.incX(-5);
break;
}
}
public void keyReleased(KeyEvent e) { }
public void keyTyped(KeyEvent e) { }
}
The main:
package milk;
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.JFrame;
#SuppressWarnings("serial")
public class MilkIt extends JFrame {
public MilkIt() {
add(new MilkPanel());
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(640,480);
setLocationRelativeTo(null);
setVisible(true);
}
public static void main(String[] args) {
new MilkIt();
}
}

It looks like you have set the position of the box to the point (320,240), which is indeed half of (640,480). The X,Y position of an object will actually be its topleft corner, however. Additionally, you will likely want to make a method for setting this information generically, as opposed to hard-coding it.
If you want to find an object's center position on a given axis (this works for X, Y, or Z, whether you're working in 2D or 3D (or more!?)), you want to take half of its size on that axis and subtract if from its position (which is actually a corner); the result will be the center.
The algorithm you're looking for is essentially this:
xPos = (screenXSize / 2) - (xSize / 2);
yPos = (screenYSize / 2) - (ySize / 2);
To standardize it even further, consider putting your variables in arrays based on how many dimensions you're using - then what I said about using either 2D or 3D automatically applies no matter what you're doing (you can even mix and match 2D and 3D elements in the same game, as is common for certain reasons).
for (int i = 0; i < DIMENSIONS; i++) {
pos[i] = (screenSize[i] / 2) - (size[i] / 2);
}

Creating labels along with drawlines

I have asked a question regarding custom widget but confused to whether I need it and how should proceed.
I have currently this class
public class GUIEdge {
public Node node1;
public Node node2;
public int weight;
public Color color;
public GUIEdge(Node node1, Node node2 , int cost) {
this.node1 = node1;
this.node2 = node2;
this.weight = cost;
this.color = Color.darkGray;
}
public void draw(Graphics g) {
Point p1 = node1.getLocation();
Point p2 = node2.getLocation();
g.setColor(this.color);
((Graphics2D) g).setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
g.drawLine(p1.x, p1.y, p2.x, p2.y);
}
}
Currently this draws an edge between two points but now I want that a label for the cost also gets created along with it.
I have already added handling for dragging of node and edges so what is the best way to create the label
Do I need to make a custom widget for that ? Could anyone explain that suppose making a component by extending from JComponent then I'll call it by g.mixed() where mixed is that new widget...?

Tool tips are certainly worth a look. Other choices include drawString(), translate(), or TextLayout. There are many examples available.
Addendum: The example below shows both drawString() and setToolTipText(), as suggested by #Catalina Island. For simplicity, the endpoints are relative to the component's size, so you can see the result of resizing the window.
Addendum: This use of setToolTipText() merely demonstrates the approach. As #camickr notes here, you should override getToolTipText(MouseEvent) and update the tip when the mouse is over the line or when the line is selected.
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Point;
import javax.swing.JComponent;
import javax.swing.JFrame;
/** #see https://stackoverflow.com/questions/5394364 */
public class LabeledEdge extends JComponent {
private static final int N = 20;
private Point n1, n2;
public LabeledEdge(int w, int h) {
this.setPreferredSize(new Dimension(w, h));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
this.n1 = new Point(N, N);
this.n2 = new Point(getWidth() - N, getHeight() - N);
g.drawLine(n1.x, n1.y, n2.x, n2.y);
double d = n1.distance(n2);
this.setToolTipText(String.valueOf(d));
g.drawString(String.valueOf((int) d),
(n1.x + n2.x) / 2, (n1.y + n2.y) / 2);
}
private static void display() {
JFrame f = new JFrame("EdgeLabel");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new LabeledEdge(320, 240));
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
display();
}
});
}
}

I think you can use GUIEdge extends JComponent. That way you'd get tool tip labels automatically.

Component size problem! Resizes to parent's size for reasons I'm unaware of!

I can't seem to figure out why this is happening...
My serverPaddle (it's based on a java.awt.Component) isn't coming out the right size.
I've placed System.out.println(serverPaddle.getSize()); in the thread loop and it shows that the component is the right size for 1 loop and then the next and thereafter, it's the same size as the parent (Container).
import javax.swing.JFrame;
import java.awt.Container;
import java.awt.Color;
import java.awt.Graphics;
private final int FRAMERATE = 60, THIS_MUCH = 1000/FRAMERATE,
BALL_DIAMETER = 30, BALL_SPEED = 15,
PADDLE_WIDTH = 15, PADDLE_HEIGHT = 60, PADDLE_SPEED = 30;
private final Color BALL_COLOR = Color.WHITE, PADDLE_COLOR = Color.WHITE;
private Container c;
private Ball puck;
private Paddle serverPaddle, clientPaddle;
...
private Container c;
...
c = getContentPane();
...
public void run() {
//Center puck
puck = new Ball(c.getWidth()/2 - BALL_DIAMETER/2,
c.getHeight()/2 - BALL_DIAMETER/2, BALL_SPEED);
puck.setSize(BALL_DIAMETER, BALL_DIAMETER);
puck.setForeground(BALL_COLOR);
puck.createHitbox();
puck.setMoving(true);
//West paddle
serverPaddle = new Paddle(PADDLE_WIDTH,
c.getHeight()/2 - PADDLE_HEIGHT/2,
PADDLE_SPEED);
serverPaddle.setSize(PADDLE_WIDTH, PADDLE_HEIGHT);
serverPaddle.setForeground(PADDLE_COLOR);
serverPaddle.createHitbox();
c.add(puck);
c.add(serverPaddle);
//Draw at FRAMERATE frames per second
while (true) {
System.out.println(serverPaddle.getSize());
puck.move(determineSituation());
puck.repaint();
wait(THIS_MUCH);
}
}
This is the Paddle class
import java.awt.Graphics;
import java.awt.Color;
import java.awt.event.KeyListener;
import java.awt.event.KeyEvent;
public class Paddle extends GameObject implements KeyListener {
private int x = 0, y = 0;
public Paddle(int x, int y, int speed) {
super(speed);
this.x = x;
this.y = y;
}
public void keyTyped(KeyEvent e) {
}
public void keyPressed(KeyEvent e) {
}
public void keyReleased(KeyEvent e) {
}
public void paint(Graphics g) {
setLocation(x, y);
//These two are the culprits, the size is correct when
//I use constants instead.
g.fillRect(0, 0, **getWidth()**, **getHeight()**);
updateHitbox();
}
}
My GameObject class...
import java.awt.Component;
import java.awt.Rectangle;
public class GameObject extends Component {
/* Members */
private int speed = 0;
private boolean isMoving = false;
private Rectangle hitbox;
//Dead south = 0 radians, anti-clockwise
private double direction = 0;
public GameObject(int speed) {
this.speed = speed;
}
/* Accessors */
public boolean isMoving() { return isMoving; }
public void setMoving(boolean isMoving) { this.isMoving = isMoving; }
public int getSpeed() { return speed; }
public void setSpeed(int speed) { this.speed = speed; }
public double getDirection() { return direction; }
public void setDirection(double direction) { this.direction = direction; }
public Rectangle getHitbox() { return hitbox; }
public void createHitbox() {
hitbox = new Rectangle(getX(), getY(), getWidth(), getHeight());
}
public void createHitbox(int x, int y, int width, int height) {
hitbox = new Rectangle(x, y, width, height);
}
public void updateHitbox() {
hitbox.setLocation(getX(), getY());
}
}
even when I comment all the code out for the Ball/puck, it doesn't work. Commenting out the "wait" method doesn't work as well. It just somehow changes for some reason that I don't know but I really wanna know SO I CAN FIX THIS THING!!11
Help! Thanks.
By the way, wait is just calling Thread.sleep
public void wait(int durationInMilliseconds) {
try {
Thread.sleep(durationInMilliseconds);
} catch (InterruptedException e) {
System.out.println(e);
}
}

Firstly, that is an awful lot of code. You want to be able to cut the problem down so that it is small enough that it becomes trivial. And if you want other people to help, it's generally a good idea to be able to produce a complete, compilable program that shows the problem and nothing else.
As it is, it looks as if you are using the content pane of a JFrame with the default LayoutManager. This will default to BorderLayout. When you add components without specifying constraints, they will be added to the "center". Without any side components, the center component will spread out to fill all available area.
So set an appropriate layout manager. I prefer to create a JPanel and use setContentPane, rather than have to bend my code structure around getContentPane.

Any reason you are not using Swing?

Eh...
For some very strange reason unbeknownst to me, when I add this line right below the run() method...
try {
Clip clip = AudioSystem.getClip();
//More to be written
} catch (Exception e) {}
The paddle renders (correct size) correctly.
When I remove it, the problem comes back... so... what the heck?
try {
//Clip clip = AudioSystem.getClip();
//More to be written
} catch (Exception e) {}

You might like this Java 2D games tutorial, featuring a Breakout style game.