|
1
|
|
|
package example; |
|
2
|
|
|
|
|
3
|
|
|
import org.gannacademy.cdf.graphics.Text; |
|
4
|
|
|
import org.gannacademy.cdf.graphics.geom.Path; |
|
5
|
|
|
import org.gannacademy.cdf.graphics.ui.AppWindow; |
|
6
|
|
|
|
|
7
|
|
|
import java.awt.*; |
|
8
|
|
|
import java.awt.event.MouseEvent; |
|
9
|
|
|
import java.awt.event.MouseListener; |
|
10
|
|
|
import java.awt.geom.PathIterator; |
|
11
|
|
|
import java.awt.geom.Point2D; |
|
12
|
|
|
|
|
13
|
|
|
public class RotationExample extends AppWindow implements MouseListener { |
|
14
|
|
|
private static final double |
|
15
|
|
|
BASE = 50, |
|
16
|
|
|
HEIGHT = 100, |
|
17
|
|
|
THETA = Math.PI / 180.0, |
|
18
|
|
|
CROSSHAIR_ARM = 20; |
|
19
|
|
|
private Path path, crosshair; |
|
|
|
|
|
|
20
|
|
|
private double x, y; |
|
|
|
|
|
|
21
|
|
|
private boolean mouseDown; |
|
22
|
|
|
private int button; |
|
23
|
|
|
|
|
24
|
|
|
@Override |
|
25
|
|
|
protected void setup() { |
|
26
|
|
|
// show instructions to user |
|
27
|
|
|
new Text("Left, middle, or right-click to rotate the triangle", 10, 40, getDrawingPanel()); |
|
|
|
|
|
|
28
|
|
|
x = getDrawingPanel().getWidth() / 2.0; |
|
29
|
|
|
|
|
30
|
|
|
// calculate top point of triangle |
|
31
|
|
|
y = (getDrawingPanel().getHeight() - HEIGHT) / 2.0; |
|
32
|
|
|
|
|
33
|
|
|
defineAnchorPointCrosshair(); |
|
34
|
|
|
defineTriangle(); |
|
35
|
|
|
|
|
36
|
|
|
// align crosshair to center of gravity |
|
37
|
|
|
Point2D center = getCentroid(); |
|
38
|
|
|
crosshair.setLocation(center.getX() - CROSSHAIR_ARM, center.getY() - CROSSHAIR_ARM); |
|
39
|
|
|
|
|
40
|
|
|
// register to be notified of mouse events (and assume no one is clicking right now) |
|
41
|
|
|
mouseDown = false; |
|
42
|
|
|
getDrawingPanel().addMouseListener(this); |
|
43
|
|
|
getDrawingPanel().requestFocus(); |
|
44
|
|
|
} |
|
45
|
|
|
|
|
46
|
|
|
private void defineTriangle() { |
|
47
|
|
|
path = new Path(getDrawingPanel()); |
|
48
|
|
|
path.moveTo(x, y); // move to top point |
|
49
|
|
|
path.lineTo(x + BASE / 2.0, y + HEIGHT); // line to bottom-right point |
|
50
|
|
|
path.lineTo(x - BASE / 2.0, y + HEIGHT); // line to bottom-left point |
|
51
|
|
|
path.lineTo(x, y); |
|
52
|
|
|
path.setStroke(new BasicStroke(2, BasicStroke.CAP_ROUND, BasicStroke.JOIN_MITER)); |
|
53
|
|
|
} |
|
54
|
|
|
|
|
55
|
|
|
private void defineAnchorPointCrosshair() { |
|
56
|
|
|
crosshair = new Path(getDrawingPanel()); |
|
57
|
|
|
crosshair.moveTo(CROSSHAIR_ARM, 0); |
|
58
|
|
|
crosshair.lineTo(CROSSHAIR_ARM, CROSSHAIR_ARM * 2); |
|
59
|
|
|
crosshair.moveTo(0, CROSSHAIR_ARM); |
|
60
|
|
|
crosshair.lineTo(CROSSHAIR_ARM * 2, CROSSHAIR_ARM); |
|
61
|
|
|
crosshair.setStrokeColor(Color.RED); |
|
62
|
|
|
} |
|
63
|
|
|
|
|
64
|
|
|
@Override |
|
65
|
|
|
protected void loop() { |
|
66
|
|
|
if (mouseDown) { |
|
67
|
|
|
|
|
68
|
|
|
double theta = THETA; // default, rotate clockwise around mouse |
|
69
|
|
|
double x = this.x, y = this.y; // default, use whatever (roundRect, ellipse) is currently set for axis of rotation |
|
|
|
|
|
|
70
|
|
|
|
|
71
|
|
|
if (button == MouseEvent.BUTTON1) theta *= -1; // left button, rotate counter-clockwise around mouse |
|
72
|
|
|
|
|
73
|
|
|
else if (button == MouseEvent.BUTTON2) { // middle button, rotate around center of gravity |
|
74
|
|
|
// use center of gravity calculation as rotation axis |
|
75
|
|
|
Point2D center = getCentroid(); |
|
76
|
|
|
x = center.getX(); |
|
77
|
|
|
y = center.getY(); |
|
78
|
|
|
} |
|
79
|
|
|
|
|
80
|
|
|
// rotate, using any adjustments to theta and axis of rotiation |
|
81
|
|
|
path.rotate(theta, x, y); |
|
82
|
|
|
crosshair.setLocation(x - CROSSHAIR_ARM, y - CROSSHAIR_ARM); |
|
83
|
|
|
} |
|
84
|
|
|
sleep(25); |
|
85
|
|
|
} |
|
86
|
|
|
|
|
87
|
|
|
public Point2D getCentroid() { |
|
88
|
|
|
double[] coords = new double[6]; // to hold coordinates |
|
89
|
|
|
double x = 0, y = 0; // tally roundRect and ellipse-coordinates |
|
|
|
|
|
|
90
|
|
|
int points = 0; // haven't visited any points yet! |
|
91
|
|
|
for (PathIterator i = path.getPathIterator(null); !i.isDone(); i.next()) { |
|
92
|
|
|
switch (i.currentSegment(coords)) { |
|
93
|
|
|
case PathIterator.SEG_MOVETO: |
|
94
|
|
|
case PathIterator.SEG_LINETO: |
|
95
|
|
|
x += coords[0]; |
|
96
|
|
|
y += coords[1]; |
|
97
|
|
|
break; |
|
98
|
|
|
case PathIterator.SEG_QUADTO: |
|
99
|
|
|
x += coords[2]; |
|
100
|
|
|
y += coords[3]; |
|
101
|
|
|
break; |
|
102
|
|
|
case PathIterator.SEG_CUBICTO: |
|
103
|
|
|
x += coords[4]; |
|
104
|
|
|
y += coords[5]; |
|
105
|
|
|
break; |
|
106
|
|
|
case PathIterator.SEG_CLOSE: |
|
107
|
|
|
default: |
|
108
|
|
|
// do nothing |
|
109
|
|
|
} |
|
110
|
|
|
points++; |
|
111
|
|
|
} |
|
112
|
|
|
|
|
113
|
|
|
// package (roundRect, ellipse) coordinates into r single object |
|
114
|
|
|
return new Point2D.Double(x / points, y / points); |
|
|
|
|
|
|
115
|
|
|
} |
|
116
|
|
|
|
|
117
|
|
|
@Override |
|
118
|
|
|
public void mouseClicked(MouseEvent e) { |
|
|
|
|
|
|
119
|
|
|
} |
|
120
|
|
|
|
|
121
|
|
|
@Override |
|
122
|
|
|
public void mousePressed(MouseEvent e) { |
|
123
|
|
|
mouseDown = true; |
|
124
|
|
|
button = e.getButton(); |
|
125
|
|
|
x = e.getX(); |
|
126
|
|
|
y = e.getY(); |
|
127
|
|
|
} |
|
128
|
|
|
|
|
129
|
|
|
@Override |
|
130
|
|
|
public void mouseReleased(MouseEvent e) { |
|
131
|
|
|
mouseDown = false; |
|
132
|
|
|
} |
|
133
|
|
|
|
|
134
|
|
|
@Override |
|
135
|
|
|
public void mouseEntered(MouseEvent e) { |
|
|
|
|
|
|
136
|
|
|
} |
|
137
|
|
|
|
|
138
|
|
|
@Override |
|
139
|
|
|
public void mouseExited(MouseEvent e) { |
|
|
|
|
|
|
140
|
|
|
} |
|
141
|
|
|
|
|
142
|
|
|
public static void main(String[] args) { |
|
143
|
|
|
new RotationExample(); |
|
144
|
|
|
} |
|
145
|
|
|
} |
|
146
|
|
|
|
gann-cdf /
graphics
Seth Battis
Loading history...