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
|
/*
Bullet for XNA Copyright (c) 2003-2007 Vsevolod Klementjev http://www.codeplex.com/xnadevru
Bullet original C++ version Copyright (c) 2003-2007 Erwin Coumans http://bulletphysics.com
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
using System;
using System.Collections.Generic;
using System.Text;
using MonoXnaCompactMaths;
namespace XnaDevRu.BulletX
{
/// <summary>
/// GjkConvexCast performs a raycast on a convex object using support mapping.
/// </summary>
public class GjkConvexCast : IConvexCast
{
private VoronoiSimplexSolver _simplexSolver;
private ConvexShape _convexA, _convexB;
public GjkConvexCast(ConvexShape convexShapeA, ConvexShape convexShapeB, VoronoiSimplexSolver solver)
{
_simplexSolver = solver;
_convexA = convexShapeA;
_convexB = convexShapeB;
}
#region IConvexCast Members
/// <summary>
/// cast a convex against another convex object
/// </summary>
/// <param name="fromA"></param>
/// <param name="toA"></param>
/// <param name="fromB"></param>
/// <param name="toB"></param>
/// <param name="result"></param>
/// <returns></returns>
public bool CalcTimeOfImpact(Matrix fromA, Matrix toA, Matrix fromB, Matrix toB, CastResult result)
{
MinkowskiSumShape combined = new MinkowskiSumShape(_convexA, _convexB);
Matrix rayFromLocalA = MathHelper.InvertMatrix(fromA) * fromB;
Matrix rayToLocalA = MathHelper.InvertMatrix(toA) * toB;
Matrix transformA = fromA;
Matrix transformB = fromB;
transformA.Translation = new Vector3(0, 0, 0);
transformB.Translation = new Vector3(0, 0, 0);
combined.TransformA = transformA;
combined.TransformB = transformB;
float radius = 0.01f;
float lambda = 0;
Vector3 s = rayFromLocalA.Translation;
Vector3 r = rayToLocalA.Translation - rayFromLocalA.Translation;
Vector3 x = s;
Vector3 n = new Vector3();
Vector3 c = new Vector3();
bool hasResult = false;
float lastLambda = lambda;
IConvexPenetrationDepthSolver penSolver = null;
Matrix identityTransform = Matrix.Identity;
SphereShape raySphere = new SphereShape(0.0f);
raySphere.Margin=0.0f;
Matrix sphereTransform = Matrix.Identity;
sphereTransform.Translation = rayFromLocalA.Translation;
result.DrawCoordSystem(sphereTransform);
{
PointCollector pointCollector = new PointCollector();
GjkPairDetector gjk = new GjkPairDetector(raySphere, combined, _simplexSolver, penSolver);
GjkPairDetector.ClosestPointInput input = new DiscreteCollisionDetectorInterface.ClosestPointInput();
input.TransformA = sphereTransform;
input.TransformB = identityTransform;
gjk.GetClosestPoints(input, pointCollector, null);
hasResult = pointCollector.HasResult;
c = pointCollector.PointInWorld;
n = pointCollector.NormalOnBInWorld;
}
if (hasResult)
{
float dist = (c - x).Length();
if (dist < radius)
{
lastLambda = 1.0f;
}
while (dist > radius)
{
n = x - c;
float dot = Vector3.Dot(n, r);
if (dot >= -(MathHelper.Epsilon * MathHelper.Epsilon)) return false;
lambda = lambda - Vector3.Distance(n, n) / dot;
if (lambda <= lastLambda) break;
lastLambda = lambda;
x = s + lambda * r;
sphereTransform.Translation = x;
result.DrawCoordSystem(sphereTransform);
PointCollector pointCollector = new PointCollector();
GjkPairDetector gjk = new GjkPairDetector(raySphere, combined, _simplexSolver, penSolver);
GjkPairDetector.ClosestPointInput input = new DiscreteCollisionDetectorInterface.ClosestPointInput();
input.TransformA = sphereTransform;
input.TransformB = identityTransform;
gjk.GetClosestPoints(input, pointCollector, null);
if (pointCollector.HasResult)
{
if (pointCollector.Distance < 0.0f)
{
result.Fraction = lastLambda;
result.Normal = n;
return true;
}
c = pointCollector.PointInWorld;
dist = (c - x).Length();
}
else
{
return false;
}
}
if (lastLambda < 1.0f)
{
result.Fraction = lastLambda;
result.Normal = n;
return true;
}
}
return false;
}
#endregion
}
}
|
