1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
|
class Component {
constructor(context, radius, color, x, y, direction, id) {
this.rayLength = 40;
this.turnStepAmount = 5;
this.stepAmount = 4;
this.radius = radius;
this.x = x;
this.y = y;
this.direction = direction;
this.color = color;
this.fieldOfView = 180;
this.id = id;
this.boidBuffer = 20;
this.update(context);
}
move(context, boids) {
// this.direction += Math.random() * (2 * this.turnStepAmount) - this.turnStepAmount
this.direction = this.findNextRay(context, boids);
var vector = this.detectionPoint(this.x, this.y, this.stepAmount, this.direction);
this.x = vector.x;
this.y = vector.y;
this.update(context);
}
buildRays() {
let rays = new Array();
let rayInteval = 2;
let noOfSteps = this.fieldOfView / rayInteval;
for (let i = 0; i < noOfSteps / 2; i++) {
if (i != 0) {
rays.push(rayInteval * -i);
}
rays.push(rayInteval * i);
}
return rays;
}
findNextRay(context, boids) {
let rays = this.buildRays();
for (let i = 0; i < rays.length; i++) {
let tweakAngle = 0;
// if (Math.random() > 0.95) {
// tweakAngle = this.turnStepAmount * Math.random() * 5;
// }
let rayAngle = tweakAngle + this.direction + rays[i];
if (i == 0 && this.detectBoid(context, rayAngle, boids)) {
continue;
}
if (this.detectBox(context, context.canvas.width, context.canvas.height, rayAngle)) {
continue;
}
return rayAngle;
}
console.log(this.x, this.y);
console.log('cannot find suitable ray');
}
detectBoid(context, direction, boids) {
for (let i = 0; i < boids.length; i++) {
// rule out ourselves
if (this.id == boids[i].id) {
continue;
}
let thisFututrePosition = this.detectionPoint(this.x, this.y, this.boidBuffer, direction);
let thisPath = {
x1: this.x,
y1: this.y,
x2: thisFututrePosition.x,
y2: thisFututrePosition.y
};
let boidFuturePosition = this.detectionPoint(boids[i].x, boids[i].y, boids[i].boidBuffer, boids[i].direction);
let boidPath = {
x1: boids[i].x,
y1: boids[i].y,
x2: boidFuturePosition.x,
y2: boidFuturePosition.y
};
let thisIntersectsBoid = this.pathsIntersect(
thisPath.x1, thisPath.y1, thisPath.x2, thisPath.y2, boidPath.x1, boidPath.y1, boidPath.x2, boidPath.y2
);
if (thisIntersectsBoid) {
return true;
}
}
return false;
}
pathsIntersect(x1, y1, x2, y2, x3, y3, x4, y4) {
// Check if none of the lines are of length 0
if ((x1 === x2 && y1 === y2) || (x3 === x4 && y3 === y4)) {
return false
}
let denominator = ((y4 - y3) * (x2 - x1) - (x4 - x3) * (y2 - y1))
// // Lines are parallel
// if (denominator === 0) {
// return false
// }
let ua = ((x4 - x3) * (y1 - y3) - (y4 - y3) * (x1 - x3)) / denominator
let ub = ((x2 - x1) * (y1 - y3) - (y2 - y1) * (x1 - x3)) / denominator
// is the intersection along the segments
if (ua < 0 || ua > 1 || ub < 0 || ub > 1) {
return false
}
// Return a object with the x and y coordinates of the intersection
let x = x1 + ua * (x2 - x1)
let y = y1 + ua * (y2 - y1)
return {
x,
y
}
}
detectBox(context, width, height, direction) {
let perceptionVector = this.detectionPoint(this.x, this.y, this.rayLength, direction);
if (perceptionVector.x - this.radius < 0 ||
perceptionVector.y - this.radius < 0 ||
perceptionVector.x + this.radius > width - 0 ||
perceptionVector.y + this.radius > height - 0
) {
return true;
}
return false;
}
update(context) {
this.drawBoid(context);
this.drawRay(context, this.x, this.y, this.rayLength, this.direction);
}
drawBoid(context) {
context.beginPath();
context.fillStyle = "blue";
context.arc(this.x, this.y, this.radius, 0, 2 * Math.PI);
context.stroke();
context.restore();
}
drawRay(context, x, y, perceptionDistance, direction) {
context.lineWidth = 1;
context.beginPath();
this.lineToAngle(context, x, y, perceptionDistance, direction);
context.stroke();
context.restore();
}
lineToAngle(context, x1, y1, length, angle) {
angle *= Math.PI / 180;
var x2 = x1 + length * Math.cos(angle),
y2 = y1 + length * Math.sin(angle);
context.moveTo(x1, y1);
context.lineTo(x2, y2);
return {
x: x2,
y: y2
};
}
detectionPoint(x1, y1, length, angle) {
angle *= Math.PI / 180;
var x2 = x1 + length * Math.cos(angle),
y2 = y1 + length * Math.sin(angle);
return {
x: x2,
y: y2
};
}
}
|
