1 /*! \file btGImpactShape.h
2 \author Francisco Leon Najera
5 This source file is part of GIMPACT Library.
7 For the latest info, see http://gimpact.sourceforge.net/
9 Copyright (c) 2007 Francisco Leon Najera. C.C. 80087371.
10 email: projectileman@yahoo.com
13 This software is provided 'as-is', without any express or implied warranty.
14 In no event will the authors be held liable for any damages arising from the use of this software.
15 Permission is granted to anyone to use this software for any purpose,
16 including commercial applications, and to alter it and redistribute it freely,
17 subject to the following restrictions:
19 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.
20 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
21 3. This notice may not be removed or altered from any source distribution.
24 #ifndef GIMPACT_TRIANGLE_SHAPE_EX_H
25 #define GIMPACT_TRIANGLE_SHAPE_EX_H
27 #include "BulletCollision/CollisionShapes/btCollisionShape.h"
28 #include "BulletCollision/CollisionShapes/btTriangleShape.h"
29 #include "btBoxCollision.h"
30 #include "btClipPolygon.h"
31 #include "btGeometryOperations.h"
33 #define MAX_TRI_CLIPPING 16
35 //! Structure for collision
36 struct GIM_TRIANGLE_CONTACT
38 btScalar m_penetration_depth;
40 btVector4 m_separating_normal;
41 btVector3 m_points[MAX_TRI_CLIPPING];
43 SIMD_FORCE_INLINE void copy_from(const GIM_TRIANGLE_CONTACT& other)
45 m_penetration_depth = other.m_penetration_depth;
46 m_separating_normal = other.m_separating_normal;
47 m_point_count = other.m_point_count;
48 int i = m_point_count;
51 m_points[i] = other.m_points[i];
55 GIM_TRIANGLE_CONTACT()
59 GIM_TRIANGLE_CONTACT(const GIM_TRIANGLE_CONTACT& other)
64 //! classify points that are closer
65 void merge_points(const btVector4& plane,
66 btScalar margin, const btVector3* points, int point_count);
69 class btPrimitiveTriangle
72 btVector3 m_vertices[3];
76 btPrimitiveTriangle() : m_margin(0.01f)
80 SIMD_FORCE_INLINE void buildTriPlane()
82 btVector3 normal = (m_vertices[1] - m_vertices[0]).cross(m_vertices[2] - m_vertices[0]);
84 m_plane.setValue(normal[0], normal[1], normal[2], m_vertices[0].dot(normal));
87 //! Test if triangles could collide
88 bool overlap_test_conservative(const btPrimitiveTriangle& other);
90 //! Calcs the plane which is paralele to the edge and perpendicular to the triangle plane
92 \pre this triangle must have its plane calculated.
94 SIMD_FORCE_INLINE void get_edge_plane(int edge_index, btVector4& plane) const
96 const btVector3& e0 = m_vertices[edge_index];
97 const btVector3& e1 = m_vertices[(edge_index + 1) % 3];
98 bt_edge_plane(e0, e1, m_plane, plane);
101 void applyTransform(const btTransform& t)
103 m_vertices[0] = t(m_vertices[0]);
104 m_vertices[1] = t(m_vertices[1]);
105 m_vertices[2] = t(m_vertices[2]);
108 //! Clips the triangle against this
110 \pre clipped_points must have MAX_TRI_CLIPPING size, and this triangle must have its plane calculated.
111 \return the number of clipped points
113 int clip_triangle(btPrimitiveTriangle& other, btVector3* clipped_points);
115 //! Find collision using the clipping method
117 \pre this triangle and other must have their triangles calculated
119 bool find_triangle_collision_clip_method(btPrimitiveTriangle& other, GIM_TRIANGLE_CONTACT& contacts);
122 //! Helper class for colliding Bullet Triangle Shapes
124 This class implements a better getAabb method than the previous btTriangleShape class
126 class btTriangleShapeEx : public btTriangleShape
129 btTriangleShapeEx() : btTriangleShape(btVector3(0, 0, 0), btVector3(0, 0, 0), btVector3(0, 0, 0))
133 btTriangleShapeEx(const btVector3& p0, const btVector3& p1, const btVector3& p2) : btTriangleShape(p0, p1, p2)
137 btTriangleShapeEx(const btTriangleShapeEx& other) : btTriangleShape(other.m_vertices1[0], other.m_vertices1[1], other.m_vertices1[2])
141 virtual void getAabb(const btTransform& t, btVector3& aabbMin, btVector3& aabbMax) const
143 btVector3 tv0 = t(m_vertices1[0]);
144 btVector3 tv1 = t(m_vertices1[1]);
145 btVector3 tv2 = t(m_vertices1[2]);
147 btAABB trianglebox(tv0, tv1, tv2, m_collisionMargin);
148 aabbMin = trianglebox.m_min;
149 aabbMax = trianglebox.m_max;
152 void applyTransform(const btTransform& t)
154 m_vertices1[0] = t(m_vertices1[0]);
155 m_vertices1[1] = t(m_vertices1[1]);
156 m_vertices1[2] = t(m_vertices1[2]);
159 SIMD_FORCE_INLINE void buildTriPlane(btVector4& plane) const
161 btVector3 normal = (m_vertices1[1] - m_vertices1[0]).cross(m_vertices1[2] - m_vertices1[0]);
163 plane.setValue(normal[0], normal[1], normal[2], m_vertices1[0].dot(normal));
166 bool overlap_test_conservative(const btTriangleShapeEx& other);
169 #endif //GIMPACT_TRIANGLE_MESH_SHAPE_H