1 /*! \file btGImpactShape.h 2 \author Francisco Leon Najera 3 */ 4 /* 5 This source file is part of GIMPACT Library. 6 7 For the latest info, see http://gimpact.sourceforge.net/ 8 9 Copyright (c) 2007 Francisco Leon Najera. C.C. 80087371. 10 email: projectileman@yahoo.com 11 12 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: 18 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. 22 */ 23 24 #ifndef GIMPACT_TRIANGLE_SHAPE_EX_H 25 #define GIMPACT_TRIANGLE_SHAPE_EX_H 26 27 #include "BulletCollision/CollisionShapes/btCollisionShape.h" 28 #include "BulletCollision/CollisionShapes/btTriangleShape.h" 29 #include "btBoxCollision.h" 30 #include "btClipPolygon.h" 31 #include "btGeometryOperations.h" 32 33 #define MAX_TRI_CLIPPING 16 34 35 //! Structure for collision 36 struct GIM_TRIANGLE_CONTACT 37 { 38 btScalar m_penetration_depth; 39 int m_point_count; 40 btVector4 m_separating_normal; 41 btVector3 m_points[MAX_TRI_CLIPPING]; 42 copy_fromGIM_TRIANGLE_CONTACT43 SIMD_FORCE_INLINE void copy_from(const GIM_TRIANGLE_CONTACT& other) 44 { 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; 49 while (i--) 50 { 51 m_points[i] = other.m_points[i]; 52 } 53 } 54 GIM_TRIANGLE_CONTACTGIM_TRIANGLE_CONTACT55 GIM_TRIANGLE_CONTACT() 56 { 57 } 58 GIM_TRIANGLE_CONTACTGIM_TRIANGLE_CONTACT59 GIM_TRIANGLE_CONTACT(const GIM_TRIANGLE_CONTACT& other) 60 { 61 copy_from(other); 62 } 63 64 //! classify points that are closer 65 void merge_points(const btVector4& plane, 66 btScalar margin, const btVector3* points, int point_count); 67 }; 68 69 class btPrimitiveTriangle 70 { 71 public: 72 btVector3 m_vertices[3]; 73 btVector4 m_plane; 74 btScalar m_margin; 75 btScalar m_dummy; btPrimitiveTriangle()76 btPrimitiveTriangle() : m_margin(0.01f) 77 { 78 } 79 buildTriPlane()80 SIMD_FORCE_INLINE void buildTriPlane() 81 { 82 btVector3 normal = (m_vertices[1] - m_vertices[0]).cross(m_vertices[2] - m_vertices[0]); 83 normal.normalize(); 84 m_plane.setValue(normal[0], normal[1], normal[2], m_vertices[0].dot(normal)); 85 } 86 87 //! Test if triangles could collide 88 bool overlap_test_conservative(const btPrimitiveTriangle& other); 89 90 //! Calcs the plane which is paralele to the edge and perpendicular to the triangle plane 91 /*! 92 \pre this triangle must have its plane calculated. 93 */ get_edge_plane(int edge_index,btVector4 & plane)94 SIMD_FORCE_INLINE void get_edge_plane(int edge_index, btVector4& plane) const 95 { 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); 99 } 100 applyTransform(const btTransform & t)101 void applyTransform(const btTransform& t) 102 { 103 m_vertices[0] = t(m_vertices[0]); 104 m_vertices[1] = t(m_vertices[1]); 105 m_vertices[2] = t(m_vertices[2]); 106 } 107 108 //! Clips the triangle against this 109 /*! 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 112 */ 113 int clip_triangle(btPrimitiveTriangle& other, btVector3* clipped_points); 114 115 //! Find collision using the clipping method 116 /*! 117 \pre this triangle and other must have their triangles calculated 118 */ 119 bool find_triangle_collision_clip_method(btPrimitiveTriangle& other, GIM_TRIANGLE_CONTACT& contacts); 120 }; 121 122 //! Helper class for colliding Bullet Triangle Shapes 123 /*! 124 This class implements a better getAabb method than the previous btTriangleShape class 125 */ 126 class btTriangleShapeEx : public btTriangleShape 127 { 128 public: btTriangleShapeEx()129 btTriangleShapeEx() : btTriangleShape(btVector3(0, 0, 0), btVector3(0, 0, 0), btVector3(0, 0, 0)) 130 { 131 } 132 btTriangleShapeEx(const btVector3 & p0,const btVector3 & p1,const btVector3 & p2)133 btTriangleShapeEx(const btVector3& p0, const btVector3& p1, const btVector3& p2) : btTriangleShape(p0, p1, p2) 134 { 135 } 136 btTriangleShapeEx(const btTriangleShapeEx & other)137 btTriangleShapeEx(const btTriangleShapeEx& other) : btTriangleShape(other.m_vertices1[0], other.m_vertices1[1], other.m_vertices1[2]) 138 { 139 } 140 getAabb(const btTransform & t,btVector3 & aabbMin,btVector3 & aabbMax)141 virtual void getAabb(const btTransform& t, btVector3& aabbMin, btVector3& aabbMax) const 142 { 143 btVector3 tv0 = t(m_vertices1[0]); 144 btVector3 tv1 = t(m_vertices1[1]); 145 btVector3 tv2 = t(m_vertices1[2]); 146 147 btAABB trianglebox(tv0, tv1, tv2, m_collisionMargin); 148 aabbMin = trianglebox.m_min; 149 aabbMax = trianglebox.m_max; 150 } 151 applyTransform(const btTransform & t)152 void applyTransform(const btTransform& t) 153 { 154 m_vertices1[0] = t(m_vertices1[0]); 155 m_vertices1[1] = t(m_vertices1[1]); 156 m_vertices1[2] = t(m_vertices1[2]); 157 } 158 buildTriPlane(btVector4 & plane)159 SIMD_FORCE_INLINE void buildTriPlane(btVector4& plane) const 160 { 161 btVector3 normal = (m_vertices1[1] - m_vertices1[0]).cross(m_vertices1[2] - m_vertices1[0]); 162 normal.normalize(); 163 plane.setValue(normal[0], normal[1], normal[2], m_vertices1[0].dot(normal)); 164 } 165 166 bool overlap_test_conservative(const btTriangleShapeEx& other); 167 }; 168 169 #endif //GIMPACT_TRIANGLE_MESH_SHAPE_H 170