/*
* Copyright (c) 2006-2009 Erin Catto http://www.gphysics.com
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 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.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
#ifndef B2_SETTINGS_H
#define B2_SETTINGS_H
#include
#include
#define B2_NOT_USED(x) ((void)(x))
#define b2Assert(A) assert(A)
typedef signed char int8;
typedef signed short int16;
typedef signed int int32;
typedef unsigned char uint8;
typedef unsigned short uint16;
typedef unsigned int uint32;
typedef float float32;
#define b2_maxFloat FLT_MAX
#define b2_epsilon FLT_EPSILON
#define b2_pi 3.14159265359f
/// @file
/// Global tuning constants based on meters-kilograms-seconds (MKS) units.
///
// Collision
/// The maximum number of contact points between two convex shapes.
#define b2_maxManifoldPoints 2
/// The maximum number of vertices on a convex polygon.
#define b2_maxPolygonVertices 8
/// This is used to fatten AABBs in the dynamic tree. This allows proxies
/// to move by a small amount without triggering a tree adjustment.
/// This is in meters.
#define b2_aabbExtension 0.1f
/// This is used to fatten AABBs in the dynamic tree. This is used to predict
/// the future position based on the current displacement.
/// This is a dimensionless multiplier.
#define b2_aabbMultiplier 2.0f
/// A small length used as a collision and constraint tolerance. Usually it is
/// chosen to be numerically significant, but visually insignificant.
#define b2_linearSlop 0.005f
/// A small angle used as a collision and constraint tolerance. Usually it is
/// chosen to be numerically significant, but visually insignificant.
#define b2_angularSlop (2.0f / 180.0f * b2_pi)
/// The radius of the polygon/edge shape skin. This should not be modified. Making
/// this smaller means polygons will have an insufficient buffer for continuous collision.
/// Making it larger may create artifacts for vertex collision.
#define b2_polygonRadius (2.0f * b2_linearSlop)
// Dynamics
/// Maximum number of contacts to be handled to solve a TOI impact.
#define b2_maxTOIContacts 32
/// A velocity threshold for elastic collisions. Any collision with a relative linear
/// velocity below this threshold will be treated as inelastic.
#define b2_velocityThreshold 1.0f
/// The maximum linear position correction used when solving constraints. This helps to
/// prevent overshoot.
#define b2_maxLinearCorrection 0.2f
/// The maximum angular position correction used when solving constraints. This helps to
/// prevent overshoot.
#define b2_maxAngularCorrection (8.0f / 180.0f * b2_pi)
/// The maximum linear velocity of a body. This limit is very large and is used
/// to prevent numerical problems. You shouldn't need to adjust this.
#define b2_maxTranslation 2.0f
#define b2_maxTranslationSquared (b2_maxTranslation * b2_maxTranslation)
/// The maximum angular velocity of a body. This limit is very large and is used
/// to prevent numerical problems. You shouldn't need to adjust this.
#define b2_maxRotation (0.5f * b2_pi)
#define b2_maxRotationSquared (b2_maxRotation * b2_maxRotation)
/// This scale factor controls how fast overlap is resolved. Ideally this would be 1 so
/// that overlap is removed in one time step. However using values close to 1 often lead
/// to overshoot.
#define b2_contactBaumgarte 0.2f
// Sleep
/// The time that a body must be still before it will go to sleep.
#define b2_timeToSleep 0.5f
/// A body cannot sleep if its linear velocity is above this tolerance.
#define b2_linearSleepTolerance 0.01f
/// A body cannot sleep if its angular velocity is above this tolerance.
#define b2_angularSleepTolerance (2.0f / 180.0f * b2_pi)
// Memory Allocation
/// Implement this function to use your own memory allocator.
void* b2Alloc(int32 size);
/// If you implement b2Alloc, you should also implement this function.
void b2Free(void* mem);
/// Version numbering scheme.
/// See http://en.wikipedia.org/wiki/Software_versioning
struct b2Version
{
int32 major; ///< significant changes
int32 minor; ///< incremental changes
int32 revision; ///< bug fixes
};
/// Current version.
extern b2Version b2_version;
/// Friction mixing law. Feel free to customize this.
inline float32 b2MixFriction(float32 friction1, float32 friction2)
{
return sqrtf(friction1 * friction2);
}
/// Restitution mixing law. Feel free to customize this.
inline float32 b2MixRestitution(float32 restitution1, float32 restitution2)
{
return restitution1 > restitution2 ? restitution1 : restitution2;
}
#endif