你好，我无法将箭头从圆心绘制到下一个圆心，每个圆圈都来自其他地方的xml，我们认为尺寸为14。
为什么我的代码似乎没有做到这一点？
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.geom.AffineTransform;
import java.io.File;
import java.io.IOException;
import java.util.Vector;
import javax.swing.JFrame;
只需设置框架
public class GRAPHICS_REPRESENTATION extends JFrame {
private Vector<Point> point_tab;
public GRAPHICS_REPRESENTATION() {
super("graphic");
point_tab = new Vector<Point>(0);
setSize(800, 800);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
画一个圆圈（从这里找到并重新加工）
// Convenience method to draw from center with radius
public void drawCircle(Graphics cg, int xCenter, int yCenter, int r) {
Graphics2D cg2 = (Graphics2D) cg.create();
cg2.drawOval(xCenter - r, yCenter - r, r, r);
}// end drawCircle
问题方法
private void disposeScene(Graphics g1, int x1, int y1, int r) {
Graphics2D g = (Graphics2D) g1.create();
AffineTransform at = g.getTransform();
AffineTransform at2 = new AffineTransform();
at2 = AffineTransform.getScaleInstance(0.5, 0.5); // scaling à faire en 1er
g.transform(at2); // prise en compte de la matrice
at2 = AffineTransform.getTranslateInstance(getWidth() / 2 + x1 + r / 2, getHeight() / 2 - y1 - r / 2); // centrage
g.transform(at2);
double angle = (double) Math.cos(0);
for (int i = 0; i < 14; i++) {
angle = Math.rint(angle / (i + 1));
g.setColor(Color.RED);
drawCircle(g, 0, 0, 2 * r);
Point center = new Point();
center.setLocation(g.getTransform().getTranslateX() / 2 + r / 2 + x1 / 2,
g.getTransform().getTranslateY() / 2 - r / 2 - y1 / 2);
point_tab.add(center);
at2.concatenate(AffineTransform.getRotateInstance(angle)); // rotation autour d'un centre
g.transform(at2);
System.out.println(point_tab.elementAt(i).getX() + "," + point_tab.elementAt(i).getY());
g.setColor(Color.BLUE);
if (i + 1 < point_tab.size()) {
drawArrow(g, point_tab.elementAt(i).getX(), point_tab.elementAt(i).getY(),
point_tab.elementAt(i + 1).getX(), point_tab.elementAt(i + 1).getY());
} else {
drawArrow(g, point_tab.elementAt(i).getX(), point_tab.elementAt(i).getY(),
point_tab.elementAt(0).getX(), point_tab.elementAt(0).getY());
}
}
g.setTransform(at);
}
从src到dst画一个箭头（在这里找到并重新编写）
private final int ARR_SIZE = 4;
private void drawArrow(Graphics g1, double xsrc, double ysrc, double xdst, double ydst) {
Graphics2D g = (Graphics2D) g1.create();
double dx = xdst - xsrc, dy = ydst - ysrc; // distances
double angle = Math.atan2(dy, dx);
int len = (int) Math.sqrt(dx * dx + dy * dy);
AffineTransform at = g.getTransform();
AffineTransform at2 = new AffineTransform();
at2=AffineTransform.getTranslateInstance(xsrc, ysrc);
at2.concatenate(AffineTransform.getRotateInstance(angle));
g.transform(at2);
// Draw horizontal arrow starting in (0, 0)
g.drawLine(0, 0, len, 0);
g.fillPolygon(new int[] { len, len - ARR_SIZE, len - ARR_SIZE, len }, new int[] { 0, -ARR_SIZE, ARR_SIZE, 0 },
4);
g.setTransform(at);
}
主要方法
public void paint(Graphics g) {
disposeScene(g, getWidth()/4,getHeight()/4,40);
}
答案 0 :(得分：2)
这是我自己找到的解决方案
/**
* @brief draw the scene with all shapes set up
* @param g1
* @param x1
* @param y1
* @param xtg
* @param r
*/
private void disposeScene(Graphics g1, int x1, int y1, XML_TO_GRAPH xtg, int r) {
Graphics2D g = (Graphics2D) g1.create();
g.translate(getWidth() / 2, getHeight() / 2);
drawCircle(g, 0, 0, (x1+y1)/2); // cercle fictif
for (int i = 0; i < xtg.getsceneVector().size(); i++) {
double angle = Math.toRadians(360.0); // radian mieux 2pi
angle = (angle*i / xtg.getsceneVector().size());
System.out.println("angle(" + i + ")=" + angle);
g.setColor(Color.RED);
drawCircle(g, (int) (Math.cos(angle) * x1), (int) (Math.sin(angle) * y1), r);
Point center_big_circle = new Point();
center_big_circle.setLocation((0), (0)); // centre du grand cercle fictif
Point center_little_circle = new Point();
center_little_circle.setLocation((Math.cos(angle) * (x1)), (Math.sin(angle) * (y1))); // décalage vers les
// bords
System.out.println("centre(" + i + ")=" + center_little_circle.getX() + "," + center_little_circle.getY());
point_tab.add(center_little_circle);
g.setColor(Color.BLACK);
drawString(g, (int) center_little_circle.getX()-r, (int) center_little_circle.getY()-r, 16, "scène : " + i);
System.out.println(point_tab.elementAt(i).getX() + "," + point_tab.elementAt(i).getY());
g.setColor(Color.BLUE);
if (i + 1 < point_tab.size()) {// si existe
drawArrow(g, point_tab.elementAt(i).getX(), point_tab.elementAt(i).getY(),
point_tab.elementAt(i + 1).getX(), point_tab.elementAt(i + 1).getY());
// g.setColor(Color.BLACK);
// drawString(g, (int)(( point_tab.elementAt(i+1).getX()-
point_tab.elementAt(i).getX())/2), (int) ((point_tab.elementAt(i+1).getY()-
point_tab.elementAt(i).getY())/2), 16, "X : " +
xtg.getcount_occurence().toString());
//idem
drawArrow(g, point_tab.elementAt(i+1).getX(), point_tab.elementAt(i+1).getY(),
point_tab.elementAt(i).getX(), point_tab.elementAt(i).getY());
// drawString(g, (int)(( point_tab.elementAt(i).getX()-
point_tab.elementAt(i+1).getX())/2), (int) ((point_tab.elementAt(i).getY()-
point_tab.elementAt(i+1).getY())/2), 16, "X : " +
xtg.getcount_occurence().toString());
}
}
}
和
// Convenience method to draw from center with radius
/**
*
* @param cg
* @param xCenter
* @param yCenter
* @param r
*/
public void drawCircle(Graphics cg, int xCenter, int yCenter, int r) {
Graphics2D cg2 = (Graphics2D) cg.create();
System.out.println("Center at: " + (xCenter - r) + "," + (yCenter - r));
cg2.drawOval(xCenter - r, yCenter - r, 2 * r, 2 * r);
}// end drawCircle
方便的drawString方法：
/**
*
* @param g1
* @param x
* @param y
* @param size
* @param str
*/
private void drawString(Graphics g1, int x, int y, int size, String str) {
Graphics2D g = (Graphics2D) g1.create();
g.setFont(new Font("Times New Roman", Font.PLAIN, size));
g.drawString(str, x, y);
}
并画画：
public void paint(Graphics g) {
disposeScene(g, (int) (getWidth() / 3), (int) (getHeight() / 3), 20);
}