Bullet Collision Detection & Physics Library
btRaycastCallback.cpp
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1 /*
2 Bullet Continuous Collision Detection and Physics Library
3 Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
4 
5 This software is provided 'as-is', without any express or implied warranty.
6 In no event will the authors be held liable for any damages arising from the use of this software.
7 Permission is granted to anyone to use this software for any purpose,
8 including commercial applications, and to alter it and redistribute it freely,
9 subject to the following restrictions:
10 
11 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.
12 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
13 3. This notice may not be removed or altered from any source distribution.
14 */
15 
16 //#include <stdio.h>
17 
24 #include "btRaycastCallback.h"
25 
27  : m_from(from),
28  m_to(to),
29  //@BP Mod
30  m_flags(flags),
31  m_hitFraction(btScalar(1.))
32 {
33 }
34 
35 void btTriangleRaycastCallback::processTriangle(btVector3* triangle, int partId, int triangleIndex)
36 {
37  const btVector3& vert0 = triangle[0];
38  const btVector3& vert1 = triangle[1];
39  const btVector3& vert2 = triangle[2];
40 
41  btVector3 v10;
42  v10 = vert1 - vert0;
43  btVector3 v20;
44  v20 = vert2 - vert0;
45 
46  btVector3 triangleNormal;
47  triangleNormal = v10.cross(v20);
48 
49  const btScalar dist = vert0.dot(triangleNormal);
50  btScalar dist_a = triangleNormal.dot(m_from);
51  dist_a -= dist;
52  btScalar dist_b = triangleNormal.dot(m_to);
53  dist_b -= dist;
54 
55  if (dist_a * dist_b >= btScalar(0.0))
56  {
57  return; // same sign
58  }
59 
60  if (((m_flags & kF_FilterBackfaces) != 0) && (dist_a <= btScalar(0.0)))
61  {
62  // Backface, skip check
63  return;
64  }
65 
66  const btScalar proj_length = dist_a - dist_b;
67  const btScalar distance = (dist_a) / (proj_length);
68  // Now we have the intersection point on the plane, we'll see if it's inside the triangle
69  // Add an epsilon as a tolerance for the raycast,
70  // in case the ray hits exacly on the edge of the triangle.
71  // It must be scaled for the triangle size.
72 
73  if (distance < m_hitFraction)
74  {
75  btScalar edge_tolerance = triangleNormal.length2();
76  edge_tolerance *= btScalar(-0.0001);
77  btVector3 point;
78  point.setInterpolate3(m_from, m_to, distance);
79  {
80  btVector3 v0p;
81  v0p = vert0 - point;
82  btVector3 v1p;
83  v1p = vert1 - point;
84  btVector3 cp0;
85  cp0 = v0p.cross(v1p);
86 
87  if ((btScalar)(cp0.dot(triangleNormal)) >= edge_tolerance)
88  {
89  btVector3 v2p;
90  v2p = vert2 - point;
91  btVector3 cp1;
92  cp1 = v1p.cross(v2p);
93  if ((btScalar)(cp1.dot(triangleNormal)) >= edge_tolerance)
94  {
95  btVector3 cp2;
96  cp2 = v2p.cross(v0p);
97 
98  if ((btScalar)(cp2.dot(triangleNormal)) >= edge_tolerance)
99  {
100  //@BP Mod
101  // Triangle normal isn't normalized
102  triangleNormal.normalize();
103 
104  //@BP Mod - Allow for unflipped normal when raycasting against backfaces
105  if (((m_flags & kF_KeepUnflippedNormal) == 0) && (dist_a <= btScalar(0.0)))
106  {
107  m_hitFraction = reportHit(-triangleNormal, distance, partId, triangleIndex);
108  }
109  else
110  {
111  m_hitFraction = reportHit(triangleNormal, distance, partId, triangleIndex);
112  }
113  }
114  }
115  }
116  }
117  }
118 }
119 
120 btTriangleConvexcastCallback::btTriangleConvexcastCallback(const btConvexShape* convexShape, const btTransform& convexShapeFrom, const btTransform& convexShapeTo, const btTransform& triangleToWorld, const btScalar triangleCollisionMargin)
121 {
122  m_convexShape = convexShape;
123  m_convexShapeFrom = convexShapeFrom;
124  m_convexShapeTo = convexShapeTo;
125  m_triangleToWorld = triangleToWorld;
126  m_hitFraction = 1.0f;
127  m_triangleCollisionMargin = triangleCollisionMargin;
128  m_allowedPenetration = 0.f;
129 }
130 
131 void btTriangleConvexcastCallback::processTriangle(btVector3* triangle, int partId, int triangleIndex)
132 {
133  btTriangleShape triangleShape(triangle[0], triangle[1], triangle[2]);
134  triangleShape.setMargin(m_triangleCollisionMargin);
135 
136  btVoronoiSimplexSolver simplexSolver;
137  btGjkEpaPenetrationDepthSolver gjkEpaPenetrationSolver;
138 
139 //#define USE_SUBSIMPLEX_CONVEX_CAST 1
140 //if you reenable USE_SUBSIMPLEX_CONVEX_CAST see commented out code below
141 #ifdef USE_SUBSIMPLEX_CONVEX_CAST
142  btSubsimplexConvexCast convexCaster(m_convexShape, &triangleShape, &simplexSolver);
143 #else
144  //btGjkConvexCast convexCaster(m_convexShape,&triangleShape,&simplexSolver);
145  btContinuousConvexCollision convexCaster(m_convexShape, &triangleShape, &simplexSolver, &gjkEpaPenetrationSolver);
146 #endif //#USE_SUBSIMPLEX_CONVEX_CAST
147 
148  btConvexCast::CastResult castResult;
149  castResult.m_fraction = btScalar(1.);
152  {
153  //add hit
154  if (castResult.m_normal.length2() > btScalar(0.0001))
155  {
156  if (castResult.m_fraction < m_hitFraction)
157  {
158  /* btContinuousConvexCast's normal is already in world space */
159  /*
160 #ifdef USE_SUBSIMPLEX_CONVEX_CAST
161  //rotate normal into worldspace
162  castResult.m_normal = m_convexShapeFrom.getBasis() * castResult.m_normal;
163 #endif //USE_SUBSIMPLEX_CONVEX_CAST
164 */
165  castResult.m_normal.normalize();
166 
167  reportHit(castResult.m_normal,
168  castResult.m_hitPoint,
169  castResult.m_fraction,
170  partId,
171  triangleIndex);
172  }
173  }
174  }
175 }
btTriangleRaycastCallback::m_hitFraction
btScalar m_hitFraction
Definition: btRaycastCallback.h:44
btTriangleConvexcastCallback::reportHit
virtual btScalar reportHit(const btVector3 &hitNormalLocal, const btVector3 &hitPointLocal, btScalar hitFraction, int partId, int triangleIndex)=0
btTriangleRaycastCallback::btTriangleRaycastCallback
btTriangleRaycastCallback(const btVector3 &from, const btVector3 &to, unsigned int flags=0)
Definition: btRaycastCallback.cpp:26
btRaycastCallback.h
btTriangleConvexcastCallback::m_triangleToWorld
btTransform m_triangleToWorld
Definition: btRaycastCallback.h:59
btScalar
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:294
btTriangleRaycastCallback::reportHit
virtual btScalar reportHit(const btVector3 &hitNormalLocal, btScalar hitFraction, int partId, int triangleIndex)=0
btTriangleConvexcastCallback::processTriangle
virtual void processTriangle(btVector3 *triangle, int partId, int triangleIndex)
Definition: btRaycastCallback.cpp:131
btSubSimplexConvexCast.h
btGjkEpaPenetrationDepthSolver.h
btVector3::cross
btVector3 cross(const btVector3 &v) const
Return the cross product between this and another vector.
Definition: btVector3.h:380
btContinuousConvexCollision::calcTimeOfImpact
virtual bool calcTimeOfImpact(const btTransform &fromA, const btTransform &toA, const btTransform &fromB, const btTransform &toB, CastResult &result)
cast a convex against another convex object
Definition: btContinuousConvexCollision.cpp:90
btConvexShape.h
btVector3::dot
btScalar dot(const btVector3 &v) const
Return the dot product.
Definition: btVector3.h:229
btContinuousConvexCollision
btContinuousConvexCollision implements angular and linear time of impact for convex objects.
Definition: btContinuousConvexCollision.h:29
btVector3::setInterpolate3
void setInterpolate3(const btVector3 &v0, const btVector3 &v1, btScalar rt)
Definition: btVector3.h:492
btGjkEpaPenetrationDepthSolver
EpaPenetrationDepthSolver uses the Expanding Polytope Algorithm to calculate the penetration depth be...
Definition: btGjkEpaPenetrationDepthSolver.h:24
btSubsimplexConvexCast
btSubsimplexConvexCast implements Gino van den Bergens' paper "Ray Casting against bteral Convex Obje...
Definition: btSubSimplexConvexCast.h:27
btTriangleShape
Definition: btTriangleShape.h:22
btTriangleShape.h
btTriangleRaycastCallback::kF_KeepUnflippedNormal
Definition: btRaycastCallback.h:36
btTriangleConvexcastCallback::m_convexShape
const btConvexShape * m_convexShape
Definition: btRaycastCallback.h:56
btConvexCast::CastResult
RayResult stores the closest result alternatively, add a callback method to decide about closest/all ...
Definition: btConvexCast.h:46
btVoronoiSimplexSolver
btVoronoiSimplexSolver is an implementation of the closest point distance algorithm from a 1-4 points...
Definition: btVoronoiSimplexSolver.h:93
btTriangleConvexcastCallback::m_convexShapeTo
btTransform m_convexShapeTo
Definition: btRaycastCallback.h:58
btTriangleConvexcastCallback::m_allowedPenetration
btScalar m_allowedPenetration
Definition: btRaycastCallback.h:62
btTransform
The btTransform class supports rigid transforms with only translation and rotation and no scaling/she...
Definition: btTransform.h:28
btTriangleRaycastCallback::kF_FilterBackfaces
Definition: btRaycastCallback.h:35
btVector3
btVector3 can be used to represent 3D points and vectors.
Definition: btVector3.h:80
btTriangleRaycastCallback::m_to
btVector3 m_to
Definition: btRaycastCallback.h:29
btConvexShape
The btConvexShape is an abstract shape interface, implemented by all convex shapes such as btBoxShape...
Definition: btConvexShape.h:31
btConvexCast::CastResult::m_fraction
btScalar m_fraction
Definition: btConvexCast.h:72
btConvexCast::CastResult::m_hitPoint
btVector3 m_hitPoint
Definition: btConvexCast.h:71
btTriangleConvexcastCallback::m_triangleCollisionMargin
btScalar m_triangleCollisionMargin
Definition: btRaycastCallback.h:61
btTriangleConvexcastCallback::btTriangleConvexcastCallback
btTriangleConvexcastCallback(const btConvexShape *convexShape, const btTransform &convexShapeFrom, const btTransform &convexShapeTo, const btTransform &triangleToWorld, const btScalar triangleCollisionMargin)
Definition: btRaycastCallback.cpp:120
btConvexCast::CastResult::m_normal
btVector3 m_normal
Definition: btConvexCast.h:70
btConvexInternalShape::setMargin
virtual void setMargin(btScalar margin)
Definition: btConvexInternalShape.h:102
btTriangleRaycastCallback::m_flags
unsigned int m_flags
Definition: btRaycastCallback.h:42
btTriangleConvexcastCallback::m_hitFraction
btScalar m_hitFraction
Definition: btRaycastCallback.h:60
btTriangleRaycastCallback::m_from
btVector3 m_from
Definition: btRaycastCallback.h:28
btContinuousConvexCollision.h
btConvexCast::CastResult::m_allowedPenetration
btScalar m_allowedPenetration
Definition: btConvexCast.h:74
btGjkConvexCast.h
btVector3::normalize
btVector3 & normalize()
Normalize this vector x^2 + y^2 + z^2 = 1.
Definition: btVector3.h:303
btTriangleConvexcastCallback::m_convexShapeFrom
btTransform m_convexShapeFrom
Definition: btRaycastCallback.h:57
btTriangleRaycastCallback::processTriangle
virtual void processTriangle(btVector3 *triangle, int partId, int triangleIndex)
Definition: btRaycastCallback.cpp:35
btVector3::length2
btScalar length2() const
Return the length of the vector squared.
Definition: btVector3.h:251