forked from MonoGame/MonoGame
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Ray.cs
executable file
·240 lines (192 loc) · 7.64 KB
/
Ray.cs
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
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
#region License
/*
MIT License
Copyright © 2006 The Mono.Xna Team
All rights reserved.
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/
#endregion License
using System;
using System.ComponentModel;
namespace Microsoft.Xna.Framework
{
public struct Ray : IEquatable<Ray>
{
#region Public Fields
public Vector3 Direction;
public Vector3 Position;
#endregion
#region Public Constructors
public Ray(Vector3 position, Vector3 direction)
{
this.Position = position;
this.Direction = direction;
}
#endregion
#region Public Methods
public override bool Equals(object obj)
{
return (obj is Ray) ? this.Equals((Ray)obj) : false;
}
public bool Equals(Ray other)
{
return this.Position.Equals(other.Position) && this.Direction.Equals(other.Direction);
}
public override int GetHashCode()
{
return Position.GetHashCode() ^ Direction.GetHashCode();
}
public float? Intersects(BoundingBox box)
{
//first test if start in box
if (Position.X >= box.Min.X
&& Position.X <= box.Max.X
&& Position.Y >= box.Min.Y
&& Position.Y <= box.Max.Y
&& Position.Z >= box.Min.Z
&& Position.Z <= box.Max.Z)
return 0.0f;// here we concidere cube is full and origine is in cube so intersect at origine
//Second we check each face
Vector3 maxT = new Vector3(-1.0f);
//Vector3 minT = new Vector3(-1.0f);
//calcul intersection with each faces
if (Position.X < box.Min.X && Direction.X != 0.0f)
maxT.X = (box.Min.X - Position.X) / Direction.X;
else if (Position.X > box.Max.X && Direction.X != 0.0f)
maxT.X = (box.Max.X - Position.X) / Direction.X;
if (Position.Y < box.Min.Y && Direction.Y != 0.0f)
maxT.Y = (box.Min.Y - Position.Y) / Direction.Y;
else if (Position.Y > box.Max.Y && Direction.Y != 0.0f)
maxT.Y = (box.Max.Y - Position.Y) / Direction.Y;
if (Position.Z < box.Min.Z && Direction.Z != 0.0f)
maxT.Z = (box.Min.Z - Position.Z) / Direction.Z;
else if (Position.Z > box.Max.Z && Direction.Z != 0.0f)
maxT.Z = (box.Max.Z - Position.Z) / Direction.Z;
//get the maximum maxT
if (maxT.X > maxT.Y && maxT.X > maxT.Z)
{
if (maxT.X < 0.0f)
return null;// ray go on opposite of face
//coordonate of hit point of face of cube
float coord = Position.Z + maxT.X * Direction.Z;
// if hit point coord ( intersect face with ray) is out of other plane coord it miss
if (coord < box.Min.Z || coord > box.Max.Z)
return null;
coord = Position.Y + maxT.X * Direction.Y;
if (coord < box.Min.Y || coord > box.Max.Y)
return null;
return maxT.X;
}
if (maxT.Y > maxT.X && maxT.Y > maxT.Z)
{
if (maxT.Y < 0.0f)
return null;// ray go on opposite of face
//coordonate of hit point of face of cube
float coord = Position.Z + maxT.Y * Direction.Z;
// if hit point coord ( intersect face with ray) is out of other plane coord it miss
if (coord < box.Min.Z || coord > box.Max.Z)
return null;
coord = Position.X + maxT.Y * Direction.X;
if (coord < box.Min.X || coord > box.Max.X)
return null;
return maxT.Y;
}
else //Z
{
if (maxT.Z < 0.0f)
return null;// ray go on opposite of face
//coordonate of hit point of face of cube
float coord = Position.X + maxT.Z * Direction.X;
// if hit point coord ( intersect face with ray) is out of other plane coord it miss
if (coord < box.Min.X || coord > box.Max.X)
return null;
coord = Position.Y + maxT.Z * Direction.Y;
if (coord < box.Min.Y || coord > box.Max.Y)
return null;
return maxT.Z;
}
}
public void Intersects(ref BoundingBox box, out float? result)
{
result = Intersects(box);
}
public float? Intersects(BoundingFrustum frustum)
{
if (frustum == null)
{
throw new ArgumentNullException("frustum");
}
return frustum.Intersects(this);
}
public float? Intersects(BoundingSphere sphere)
{
float? result;
Intersects(ref sphere, out result);
return result;
}
public float? Intersects(Plane plane)
{
throw new NotImplementedException();
}
public void Intersects(ref Plane plane, out float? result)
{
throw new NotImplementedException();
}
public void Intersects(ref BoundingSphere sphere, out float? result)
{
// Find the vector between where the ray starts the the sphere's centre
Vector3 difference = sphere.Center - this.Position;
float differenceLengthSquared = difference.LengthSquared();
float sphereRadiusSquared = sphere.Radius * sphere.Radius;
float distanceAlongRay;
// If the distance between the ray start and the sphere's centre is less than
// the radius of the sphere, it means we've intersected. N.B. checking the LengthSquared is faster.
if (differenceLengthSquared < sphereRadiusSquared)
{
result = 0.0f;
return;
}
Vector3.Dot(ref this.Direction, ref difference, out distanceAlongRay);
// If the ray is pointing away from the sphere then we don't ever intersect
if (distanceAlongRay < 0)
{
result = null;
return;
}
// Next we kinda use Pythagoras to check if we are within the bounds of the sphere
// if x = radius of sphere
// if y = distance between ray position and sphere centre
// if z = the distance we've travelled along the ray
// if x^2 + z^2 - y^2 < 0, we do not intersect
float dist = sphereRadiusSquared + distanceAlongRay * distanceAlongRay - differenceLengthSquared;
result = (dist < 0) ? null : distanceAlongRay - (float?)Math.Sqrt(dist);
}
public static bool operator !=(Ray a, Ray b)
{
return !a.Equals(b);
}
public static bool operator ==(Ray a, Ray b)
{
return a.Equals(b);
}
public override string ToString()
{
return string.Format("{{Position:{0} Direction:{1}}}", Position.ToString(), Direction.ToString());
}
#endregion
}
}