1/*
2* Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
3*
4* This software is provided 'as-is', without any express or implied
5* warranty. In no event will the authors be held liable for any damages
6* 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
9* freely, subject to the following restrictions:
10* 1. The origin of this software must not be misrepresented; you must not
11* claim that you wrote the original software. If you use this software
12* in a product, an acknowledgment in the product documentation would be
13* appreciated but is not required.
14* 2. Altered source versions must be plainly marked as such, and must not be
15* misrepresented as being the original software.
16* 3. This notice may not be removed or altered from any source distribution.
17*/
18
19#ifndef B2_SETTINGS_H
20#define B2_SETTINGS_H
21
22#include <stddef.h>
23#include <assert.h>
24#include <float.h>
25
26void loveAssert(bool test, const char *teststr);
27
28#define B2_NOT_USED(x) ((void)(x))
29//#define b2Assert(A) assert(A)
30#define b2Assert(A) loveAssert((A), #A)
31
32typedef signed char int8;
33typedef signed short int16;
34typedef signed int int32;
35typedef unsigned char uint8;
36typedef unsigned short uint16;
37typedef unsigned int uint32;
38typedef float float32;
39typedef double float64;
40
41#define b2_maxFloat FLT_MAX
42#define b2_epsilon FLT_EPSILON
43#define b2_pi 3.14159265359f
44
45/// @file
46/// Global tuning constants based on meters-kilograms-seconds (MKS) units.
47///
48
49// Collision
50
51/// The maximum number of contact points between two convex shapes. Do
52/// not change this value.
53#define b2_maxManifoldPoints 2
54
55/// The maximum number of vertices on a convex polygon. You cannot increase
56/// this too much because b2BlockAllocator has a maximum object size.
57#define b2_maxPolygonVertices 8
58
59/// This is used to fatten AABBs in the dynamic tree. This allows proxies
60/// to move by a small amount without triggering a tree adjustment.
61/// This is in meters.
62#define b2_aabbExtension 0.1f
63
64/// This is used to fatten AABBs in the dynamic tree. This is used to predict
65/// the future position based on the current displacement.
66/// This is a dimensionless multiplier.
67#define b2_aabbMultiplier 2.0f
68
69/// A small length used as a collision and constraint tolerance. Usually it is
70/// chosen to be numerically significant, but visually insignificant.
71#define b2_linearSlop 0.005f
72
73/// A small angle used as a collision and constraint tolerance. Usually it is
74/// chosen to be numerically significant, but visually insignificant.
75#define b2_angularSlop (2.0f / 180.0f * b2_pi)
76
77/// The radius of the polygon/edge shape skin. This should not be modified. Making
78/// this smaller means polygons will have an insufficient buffer for continuous collision.
79/// Making it larger may create artifacts for vertex collision.
80#define b2_polygonRadius (2.0f * b2_linearSlop)
81
82/// Maximum number of sub-steps per contact in continuous physics simulation.
83#define b2_maxSubSteps 8
84
85
86// Dynamics
87
88/// Maximum number of contacts to be handled to solve a TOI impact.
89#define b2_maxTOIContacts 32
90
91/// A velocity threshold for elastic collisions. Any collision with a relative linear
92/// velocity below this threshold will be treated as inelastic.
93#define b2_velocityThreshold 1.0f
94
95/// The maximum linear position correction used when solving constraints. This helps to
96/// prevent overshoot.
97#define b2_maxLinearCorrection 0.2f
98
99/// The maximum angular position correction used when solving constraints. This helps to
100/// prevent overshoot.
101#define b2_maxAngularCorrection (8.0f / 180.0f * b2_pi)
102
103/// The maximum linear velocity of a body. This limit is very large and is used
104/// to prevent numerical problems. You shouldn't need to adjust this.
105#define b2_maxTranslation 2.0f
106#define b2_maxTranslationSquared (b2_maxTranslation * b2_maxTranslation)
107
108/// The maximum angular velocity of a body. This limit is very large and is used
109/// to prevent numerical problems. You shouldn't need to adjust this.
110#define b2_maxRotation (0.5f * b2_pi)
111#define b2_maxRotationSquared (b2_maxRotation * b2_maxRotation)
112
113/// This scale factor controls how fast overlap is resolved. Ideally this would be 1 so
114/// that overlap is removed in one time step. However using values close to 1 often lead
115/// to overshoot.
116#define b2_baumgarte 0.2f
117#define b2_toiBaugarte 0.75f
118
119
120// Sleep
121
122/// The time that a body must be still before it will go to sleep.
123#define b2_timeToSleep 0.5f
124
125/// A body cannot sleep if its linear velocity is above this tolerance.
126#define b2_linearSleepTolerance 0.01f
127
128/// A body cannot sleep if its angular velocity is above this tolerance.
129#define b2_angularSleepTolerance (2.0f / 180.0f * b2_pi)
130
131// Memory Allocation
132
133/// Implement this function to use your own memory allocator.
134void* b2Alloc(int32 size);
135
136/// If you implement b2Alloc, you should also implement this function.
137void b2Free(void* mem);
138
139/// Logging function.
140void b2Log(const char* string, ...);
141
142/// Version numbering scheme.
143/// See http://en.wikipedia.org/wiki/Software_versioning
144struct b2Version
145{
146 int32 major; ///< significant changes
147 int32 minor; ///< incremental changes
148 int32 revision; ///< bug fixes
149};
150
151/// Current version.
152extern b2Version b2_version;
153
154#endif
155