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authorJeff Ames2007-11-11 09:19:21 +0000
committerJeff Ames2007-11-11 09:19:21 +0000
commitdb174dfa2061ce35b657cd8f119f1176b53c6207 (patch)
tree7ff889f817ab0ebac5a90c6adbecf4a263239a73 /OpenSim/Region/Physics/Meshing/Simplex.cs
parentfixed chatting while sitting (diff)
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-rw-r--r--OpenSim/Region/Physics/Meshing/Simplex.cs394
1 files changed, 197 insertions, 197 deletions
diff --git a/OpenSim/Region/Physics/Meshing/Simplex.cs b/OpenSim/Region/Physics/Meshing/Simplex.cs
index 4944f22..42dbefa 100644
--- a/OpenSim/Region/Physics/Meshing/Simplex.cs
+++ b/OpenSim/Region/Physics/Meshing/Simplex.cs
@@ -1,198 +1,198 @@
1using System; 1using System;
2using System.Collections.Generic; 2using System.Collections.Generic;
3using System.Text; 3using System.Text;
4using OpenSim.Region.Physics.Manager; 4using OpenSim.Region.Physics.Manager;
5 5
6namespace OpenSim.Region.Physics.Meshing 6namespace OpenSim.Region.Physics.Meshing
7{ 7{
8 // A simplex is a section of a straight line. 8 // A simplex is a section of a straight line.
9 // It is defined by its endpoints, i.e. by two vertices 9 // It is defined by its endpoints, i.e. by two vertices
10 // Operation on vertices are 10 // Operation on vertices are
11 public class Simplex : IComparable<Simplex> 11 public class Simplex : IComparable<Simplex>
12 { 12 {
13 public Vertex v1; 13 public Vertex v1;
14 public Vertex v2; 14 public Vertex v2;
15 15
16 public Simplex(Vertex _v1, Vertex _v2) 16 public Simplex(Vertex _v1, Vertex _v2)
17 { 17 {
18 v1 = _v1; 18 v1 = _v1;
19 v2 = _v2; 19 v2 = _v2;
20 } 20 }
21 21
22 public int CompareTo(Simplex other) 22 public int CompareTo(Simplex other)
23 { 23 {
24 24
25 Vertex lv1, lv2, ov1, ov2, temp; 25 Vertex lv1, lv2, ov1, ov2, temp;
26 26
27 lv1 = v1; 27 lv1 = v1;
28 lv2 = v2; 28 lv2 = v2;
29 ov1 = other.v1; 29 ov1 = other.v1;
30 ov2 = other.v2; 30 ov2 = other.v2;
31 31
32 if (lv1 > lv2) 32 if (lv1 > lv2)
33 { 33 {
34 temp = lv1; 34 temp = lv1;
35 lv1 = lv2; 35 lv1 = lv2;
36 lv2 = temp; 36 lv2 = temp;
37 } 37 }
38 38
39 if (ov1 > ov2) 39 if (ov1 > ov2)
40 { 40 {
41 temp = ov1; 41 temp = ov1;
42 ov1 = ov2; 42 ov1 = ov2;
43 ov2 = temp; 43 ov2 = temp;
44 } 44 }
45 45
46 if (lv1 > ov1) 46 if (lv1 > ov1)
47 { 47 {
48 return 1; 48 return 1;
49 } 49 }
50 if (lv1 < ov1) 50 if (lv1 < ov1)
51 { 51 {
52 return -1; 52 return -1;
53 } 53 }
54 54
55 if (lv2 > ov2) 55 if (lv2 > ov2)
56 { 56 {
57 return 1; 57 return 1;
58 } 58 }
59 if (lv2 < ov2) 59 if (lv2 < ov2)
60 { 60 {
61 return -1; 61 return -1;
62 } 62 }
63 63
64 return 0; 64 return 0;
65 } 65 }
66 66
67 private static void intersectParameter(PhysicsVector p1, PhysicsVector r1, PhysicsVector p2, PhysicsVector r2, ref float lambda, ref float mu) 67 private static void intersectParameter(PhysicsVector p1, PhysicsVector r1, PhysicsVector p2, PhysicsVector r2, ref float lambda, ref float mu)
68 { 68 {
69 // Intersects two straights 69 // Intersects two straights
70 // p1, p2, points on the straight 70 // p1, p2, points on the straight
71 // r1, r2, directional vectors of the straight. Not necessarily of length 1! 71 // r1, r2, directional vectors of the straight. Not necessarily of length 1!
72 // note, that l, m can be scaled such, that the range 0..1 is mapped to the area between two points, 72 // note, that l, m can be scaled such, that the range 0..1 is mapped to the area between two points,
73 // thus allowing to decide whether an intersection is between two points 73 // thus allowing to decide whether an intersection is between two points
74 74
75 float r1x = r1.X; 75 float r1x = r1.X;
76 float r1y = r1.Y; 76 float r1y = r1.Y;
77 float r2x = r2.X; 77 float r2x = r2.X;
78 float r2y = r2.Y; 78 float r2y = r2.Y;
79 79
80 float denom = r1y*r2x - r1x*r2y; 80 float denom = r1y*r2x - r1x*r2y;
81 81
82 float p1x = p1.X; 82 float p1x = p1.X;
83 float p1y = p1.Y; 83 float p1y = p1.Y;
84 float p2x = p2.X; 84 float p2x = p2.X;
85 float p2y = p2.Y; 85 float p2y = p2.Y;
86 86
87 float z1=-p2x * r2y + p1x * r2y + (p2y - p1y) * r2x; 87 float z1=-p2x * r2y + p1x * r2y + (p2y - p1y) * r2x;
88 float z2=-p2x * r1y + p1x * r1y + (p2y - p1y) * r1x; 88 float z2=-p2x * r1y + p1x * r1y + (p2y - p1y) * r1x;
89 89
90 if (denom == 0.0f) // Means the straights are parallel. Either no intersection or an infinite number of them 90 if (denom == 0.0f) // Means the straights are parallel. Either no intersection or an infinite number of them
91 { 91 {
92 if (z1==0.0f) {// Means they are identical -> many, many intersections 92 if (z1==0.0f) {// Means they are identical -> many, many intersections
93 lambda = Single.NaN; 93 lambda = Single.NaN;
94 mu = Single.NaN; 94 mu = Single.NaN;
95 } else { 95 } else {
96 lambda = Single.PositiveInfinity; 96 lambda = Single.PositiveInfinity;
97 mu = Single.PositiveInfinity; 97 mu = Single.PositiveInfinity;
98 } 98 }
99 return; 99 return;
100 100
101 } 101 }
102 102
103 103
104 104
105 lambda = z1 / denom; 105 lambda = z1 / denom;
106 mu = z2 / denom; 106 mu = z2 / denom;
107 107
108 } 108 }
109 109
110 110
111 // Intersects the simplex with another one. 111 // Intersects the simplex with another one.
112 // the borders are used to deal with float inaccuracies 112 // the borders are used to deal with float inaccuracies
113 // As a rule of thumb, the borders are 113 // As a rule of thumb, the borders are
114 // lowerBorder1 : 0.0 114 // lowerBorder1 : 0.0
115 // lowerBorder2 : 0.0 115 // lowerBorder2 : 0.0
116 // upperBorder1 : 1.0 116 // upperBorder1 : 1.0
117 // upperBorder2 : 1.0 117 // upperBorder2 : 1.0
118 // Set these to values near the given parameters (e.g. 0.001 instead of 1 to exclude simplex starts safely, or to -0.001 to include them safely) 118 // Set these to values near the given parameters (e.g. 0.001 instead of 1 to exclude simplex starts safely, or to -0.001 to include them safely)
119 public static PhysicsVector Intersect( 119 public static PhysicsVector Intersect(
120 Simplex s1, 120 Simplex s1,
121 Simplex s2, 121 Simplex s2,
122 float lowerBorder1, 122 float lowerBorder1,
123 float lowerBorder2, 123 float lowerBorder2,
124 float upperBorder1, 124 float upperBorder1,
125 float upperBorder2) 125 float upperBorder2)
126 { 126 {
127 PhysicsVector firstSimplexDirection = s1.v2 - s1.v1; 127 PhysicsVector firstSimplexDirection = s1.v2 - s1.v1;
128 PhysicsVector secondSimplexDirection = s2.v2 - s2.v1; 128 PhysicsVector secondSimplexDirection = s2.v2 - s2.v1;
129 129
130 float lambda = 0.0f; 130 float lambda = 0.0f;
131 float mu = 0.0f; 131 float mu = 0.0f;
132 132
133 // Give us the parameters of an intersection. This subroutine does *not* take the constraints 133 // Give us the parameters of an intersection. This subroutine does *not* take the constraints
134 // (intersection must be between v1 and v2 and it must be in the positive direction of the ray) 134 // (intersection must be between v1 and v2 and it must be in the positive direction of the ray)
135 // into account. We do that afterwards. 135 // into account. We do that afterwards.
136 intersectParameter(s1.v1, firstSimplexDirection, s2.v1, secondSimplexDirection, ref lambda, ref mu); 136 intersectParameter(s1.v1, firstSimplexDirection, s2.v1, secondSimplexDirection, ref lambda, ref mu);
137 137
138 if (Single.IsInfinity(lambda)) // Special case. No intersection at all. directions parallel. 138 if (Single.IsInfinity(lambda)) // Special case. No intersection at all. directions parallel.
139 return null; 139 return null;
140 140
141 if (Single.IsNaN(lambda)) // Special case. many, many intersections. 141 if (Single.IsNaN(lambda)) // Special case. many, many intersections.
142 return null; 142 return null;
143 143
144 if (lambda > upperBorder1) // We're behind v2 144 if (lambda > upperBorder1) // We're behind v2
145 return null; 145 return null;
146 146
147 if (lambda < lowerBorder1) 147 if (lambda < lowerBorder1)
148 return null; 148 return null;
149 149
150 if (mu < lowerBorder2) // outside simplex 2 150 if (mu < lowerBorder2) // outside simplex 2
151 return null; 151 return null;
152 152
153 if (mu > upperBorder2) // outside simplex 2 153 if (mu > upperBorder2) // outside simplex 2
154 return null; 154 return null;
155 155
156 return s1.v1 + lambda * firstSimplexDirection; 156 return s1.v1 + lambda * firstSimplexDirection;
157 157
158 } 158 }
159 159
160 // Intersects the simplex with a ray. The ray is defined as all p=origin + lambda*direction 160 // Intersects the simplex with a ray. The ray is defined as all p=origin + lambda*direction
161 // where lambda >= 0 161 // where lambda >= 0
162 public PhysicsVector RayIntersect(Vertex origin, PhysicsVector direction, bool bEndsIncluded) 162 public PhysicsVector RayIntersect(Vertex origin, PhysicsVector direction, bool bEndsIncluded)
163 { 163 {
164 PhysicsVector simplexDirection = v2 - v1; 164 PhysicsVector simplexDirection = v2 - v1;
165 165
166 float lambda = 0.0f; 166 float lambda = 0.0f;
167 float mu = 0.0f; 167 float mu = 0.0f;
168 168
169 // Give us the parameters of an intersection. This subroutine does *not* take the constraints 169 // Give us the parameters of an intersection. This subroutine does *not* take the constraints
170 // (intersection must be between v1 and v2 and it must be in the positive direction of the ray) 170 // (intersection must be between v1 and v2 and it must be in the positive direction of the ray)
171 // into account. We do that afterwards. 171 // into account. We do that afterwards.
172 intersectParameter(v1, simplexDirection, origin, direction, ref lambda, ref mu); 172 intersectParameter(v1, simplexDirection, origin, direction, ref lambda, ref mu);
173 173
174 if (Single.IsInfinity(lambda)) // Special case. No intersection at all. directions parallel. 174 if (Single.IsInfinity(lambda)) // Special case. No intersection at all. directions parallel.
175 return null; 175 return null;
176 176
177 if (Single.IsNaN(lambda)) // Special case. many, many intersections. 177 if (Single.IsNaN(lambda)) // Special case. many, many intersections.
178 return null; 178 return null;
179 179
180 if (mu < 0.0) // We're on the wrong side of the ray 180 if (mu < 0.0) // We're on the wrong side of the ray
181 return null; 181 return null;
182 182
183 if (lambda > 1.0) // We're behind v2 183 if (lambda > 1.0) // We're behind v2
184 return null; 184 return null;
185 185
186 if (lambda == 1.0 && !bEndsIncluded) 186 if (lambda == 1.0 && !bEndsIncluded)
187 return null; // The end of the simplices are not included 187 return null; // The end of the simplices are not included
188 188
189 if (lambda < 0.0f) // we're before v1; 189 if (lambda < 0.0f) // we're before v1;
190 return null; 190 return null;
191 191
192 return this.v1 + lambda * simplexDirection; 192 return this.v1 + lambda * simplexDirection;
193 193
194 } 194 }
195 195
196 196
197 } 197 }
198} \ No newline at end of file 198} \ No newline at end of file