Blender  V3.3
btClipPolygon.h
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1 #ifndef BT_CLIP_POLYGON_H_INCLUDED
2 #define BT_CLIP_POLYGON_H_INCLUDED
3 
7 /*
8 This source file is part of GIMPACT Library.
9 
10 For the latest info, see http://gimpact.sourceforge.net/
11 
12 Copyright (c) 2007 Francisco Leon Najera. C.C. 80087371.
13 email: projectileman@yahoo.com
14 
15 
16 This software is provided 'as-is', without any express or implied warranty.
17 In no event will the authors be held liable for any damages arising from the use of this software.
18 Permission is granted to anyone to use this software for any purpose,
19 including commercial applications, and to alter it and redistribute it freely,
20 subject to the following restrictions:
21 
22 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.
23 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
24 3. This notice may not be removed or altered from any source distribution.
25 */
26 
27 #include "LinearMath/btTransform.h"
29 
31 {
32  return point.dot(plane) - plane[3];
33 }
34 
37 SIMD_FORCE_INLINE void bt_vec_blend(btVector3 &vr, const btVector3 &va, const btVector3 &vb, btScalar blend_factor)
38 {
39  vr = (1 - blend_factor) * va + blend_factor * vb;
40 }
41 
44  const btVector3 &point0,
45  const btVector3 &point1,
46  btScalar dist0,
47  btScalar dist1,
48  btVector3 *clipped,
49  int &clipped_count)
50 {
51  bool _prevclassif = (dist0 > SIMD_EPSILON);
52  bool _classif = (dist1 > SIMD_EPSILON);
53  if (_classif != _prevclassif)
54  {
55  btScalar blendfactor = -dist0 / (dist1 - dist0);
56  bt_vec_blend(clipped[clipped_count], point0, point1, blendfactor);
57  clipped_count++;
58  }
59  if (!_classif)
60  {
61  clipped[clipped_count] = point1;
62  clipped_count++;
63  }
64 }
65 
67 
71  const btVector4 &plane,
72  const btVector3 *polygon_points,
73  int polygon_point_count,
74  btVector3 *clipped)
75 {
76  int clipped_count = 0;
77 
78  //clip first point
79  btScalar firstdist = bt_distance_point_plane(plane, polygon_points[0]);
80  ;
81  if (!(firstdist > SIMD_EPSILON))
82  {
83  clipped[clipped_count] = polygon_points[0];
84  clipped_count++;
85  }
86 
87  btScalar olddist = firstdist;
88  for (int i = 1; i < polygon_point_count; i++)
89  {
90  btScalar dist = bt_distance_point_plane(plane, polygon_points[i]);
91 
93  polygon_points[i - 1], polygon_points[i],
94  olddist,
95  dist,
96  clipped,
97  clipped_count);
98 
99  olddist = dist;
100  }
101 
102  //RETURN TO FIRST point
103 
105  polygon_points[polygon_point_count - 1], polygon_points[0],
106  olddist,
107  firstdist,
108  clipped,
109  clipped_count);
110 
111  return clipped_count;
112 }
113 
115 
120  const btVector4 &plane,
121  const btVector3 &point0,
122  const btVector3 &point1,
123  const btVector3 &point2,
124  btVector3 *clipped // an allocated array of 16 points at least
125 )
126 {
127  int clipped_count = 0;
128 
129  //clip first point0
130  btScalar firstdist = bt_distance_point_plane(plane, point0);
131  ;
132  if (!(firstdist > SIMD_EPSILON))
133  {
134  clipped[clipped_count] = point0;
135  clipped_count++;
136  }
137 
138  // point 1
139  btScalar olddist = firstdist;
140  btScalar dist = bt_distance_point_plane(plane, point1);
141 
143  point0, point1,
144  olddist,
145  dist,
146  clipped,
147  clipped_count);
148 
149  olddist = dist;
150 
151  // point 2
152  dist = bt_distance_point_plane(plane, point2);
153 
155  point1, point2,
156  olddist,
157  dist,
158  clipped,
159  clipped_count);
160  olddist = dist;
161 
162  //RETURN TO FIRST point0
164  point2, point0,
165  olddist,
166  firstdist,
167  clipped,
168  clipped_count);
169 
170  return clipped_count;
171 }
172 
173 #endif // GIM_TRI_COLLISION_H_INCLUDED
in reality light always falls off quadratically Particle Retrieve the data of the particle that spawned the object for example to give variation to multiple instances of an object Point Retrieve information about points in a point cloud Retrieve the edges of an object as it appears to Cycles topology will always appear triangulated Convert a blackbody temperature to an RGB value Normal Generate a perturbed normal from an RGB normal map image Typically used for faking highly detailed surfaces Generate an OSL shader from a file or text data block Image Sample an image file as a texture Sky Generate a procedural sky texture Noise Generate fractal Perlin noise Wave Generate procedural bands or rings with noise Voronoi Generate Worley noise based on the distance to random points Typically used to generate textures such as or biological cells Brick Generate a procedural texture producing bricks Texture Retrieve multiple types of texture coordinates nTypically used as inputs for texture nodes Vector Convert a point
SIMD_FORCE_INLINE void bt_vec_blend(btVector3 &vr, const btVector3 &va, const btVector3 &vb, btScalar blend_factor)
Definition: btClipPolygon.h:37
SIMD_FORCE_INLINE btScalar bt_distance_point_plane(const btVector4 &plane, const btVector3 &point)
Definition: btClipPolygon.h:30
SIMD_FORCE_INLINE int bt_plane_clip_triangle(const btVector4 &plane, const btVector3 &point0, const btVector3 &point1, const btVector3 &point2, btVector3 *clipped)
Clips a polygon by a plane.
SIMD_FORCE_INLINE void bt_plane_clip_polygon_collect(const btVector3 &point0, const btVector3 &point1, btScalar dist0, btScalar dist1, btVector3 *clipped, int &clipped_count)
This function calcs the distance from a 3D plane.
Definition: btClipPolygon.h:43
SIMD_FORCE_INLINE int bt_plane_clip_polygon(const btVector4 &plane, const btVector3 *polygon_points, int polygon_point_count, btVector3 *clipped)
Clips a polygon by a plane.
Definition: btClipPolygon.h:70
float btScalar
The btScalar type abstracts floating point numbers, to easily switch between double and single floati...
Definition: btScalar.h:314
#define SIMD_FORCE_INLINE
Definition: btScalar.h:280
#define SIMD_EPSILON
Definition: btScalar.h:543
btVector3
btVector3 can be used to represent 3D points and vectors. It has an un-used w component to suit 16-by...
Definition: btVector3.h:82