bluecore/ode/OPCODE/OPC_BoxBoxOverlap.h

123 lines
7.6 KiB
C

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* OBB-OBB overlap test using the separating axis theorem.
* - original code by Gomez / Gamasutra (similar to Gottschalk's one in RAPID)
* - optimized for AABB trees by computing the rotation matrix once (SOLID-fashion)
* - the fabs matrix is precomputed as well and epsilon-tweaked (RAPID-style, we found this almost mandatory)
* - Class III axes can be disabled... (SOLID & Intel fashion)
* - ...or enabled to perform some profiling
* - CPU comparisons used when appropriate
* - lazy evaluation sometimes saves some work in case of early exits (unlike SOLID)
*
* \param ea [in] extents from box A
* \param ca [in] center from box A
* \param eb [in] extents from box B
* \param cb [in] center from box B
* \return true if boxes overlap
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
inline_ BOOL AABBTreeCollider::BoxBoxOverlap(const Point& ea, const Point& ca, const Point& eb, const Point& cb)
{
// Stats
mNbBVBVTests++;
float t,t2;
// Class I : A's basis vectors
float Tx = (mR1to0.m[0][0]*cb.x + mR1to0.m[1][0]*cb.y + mR1to0.m[2][0]*cb.z) + mT1to0.x - ca.x;
t = ea.x + eb.x*mAR.m[0][0] + eb.y*mAR.m[1][0] + eb.z*mAR.m[2][0];
if(GREATER(Tx, t)) return FALSE;
float Ty = (mR1to0.m[0][1]*cb.x + mR1to0.m[1][1]*cb.y + mR1to0.m[2][1]*cb.z) + mT1to0.y - ca.y;
t = ea.y + eb.x*mAR.m[0][1] + eb.y*mAR.m[1][1] + eb.z*mAR.m[2][1];
if(GREATER(Ty, t)) return FALSE;
float Tz = (mR1to0.m[0][2]*cb.x + mR1to0.m[1][2]*cb.y + mR1to0.m[2][2]*cb.z) + mT1to0.z - ca.z;
t = ea.z + eb.x*mAR.m[0][2] + eb.y*mAR.m[1][2] + eb.z*mAR.m[2][2];
if(GREATER(Tz, t)) return FALSE;
// Class II : B's basis vectors
t = Tx*mR1to0.m[0][0] + Ty*mR1to0.m[0][1] + Tz*mR1to0.m[0][2]; t2 = ea.x*mAR.m[0][0] + ea.y*mAR.m[0][1] + ea.z*mAR.m[0][2] + eb.x;
if(GREATER(t, t2)) return FALSE;
t = Tx*mR1to0.m[1][0] + Ty*mR1to0.m[1][1] + Tz*mR1to0.m[1][2]; t2 = ea.x*mAR.m[1][0] + ea.y*mAR.m[1][1] + ea.z*mAR.m[1][2] + eb.y;
if(GREATER(t, t2)) return FALSE;
t = Tx*mR1to0.m[2][0] + Ty*mR1to0.m[2][1] + Tz*mR1to0.m[2][2]; t2 = ea.x*mAR.m[2][0] + ea.y*mAR.m[2][1] + ea.z*mAR.m[2][2] + eb.z;
if(GREATER(t, t2)) return FALSE;
// Class III : 9 cross products
// Cool trick: always perform the full test for first level, regardless of settings.
// That way pathological cases (such as the pencils scene) are quickly rejected anyway !
if(mFullBoxBoxTest || mNbBVBVTests==1)
{
t = Tz*mR1to0.m[0][1] - Ty*mR1to0.m[0][2]; t2 = ea.y*mAR.m[0][2] + ea.z*mAR.m[0][1] + eb.y*mAR.m[2][0] + eb.z*mAR.m[1][0]; if(GREATER(t, t2)) return FALSE; // L = A0 x B0
t = Tz*mR1to0.m[1][1] - Ty*mR1to0.m[1][2]; t2 = ea.y*mAR.m[1][2] + ea.z*mAR.m[1][1] + eb.x*mAR.m[2][0] + eb.z*mAR.m[0][0]; if(GREATER(t, t2)) return FALSE; // L = A0 x B1
t = Tz*mR1to0.m[2][1] - Ty*mR1to0.m[2][2]; t2 = ea.y*mAR.m[2][2] + ea.z*mAR.m[2][1] + eb.x*mAR.m[1][0] + eb.y*mAR.m[0][0]; if(GREATER(t, t2)) return FALSE; // L = A0 x B2
t = Tx*mR1to0.m[0][2] - Tz*mR1to0.m[0][0]; t2 = ea.x*mAR.m[0][2] + ea.z*mAR.m[0][0] + eb.y*mAR.m[2][1] + eb.z*mAR.m[1][1]; if(GREATER(t, t2)) return FALSE; // L = A1 x B0
t = Tx*mR1to0.m[1][2] - Tz*mR1to0.m[1][0]; t2 = ea.x*mAR.m[1][2] + ea.z*mAR.m[1][0] + eb.x*mAR.m[2][1] + eb.z*mAR.m[0][1]; if(GREATER(t, t2)) return FALSE; // L = A1 x B1
t = Tx*mR1to0.m[2][2] - Tz*mR1to0.m[2][0]; t2 = ea.x*mAR.m[2][2] + ea.z*mAR.m[2][0] + eb.x*mAR.m[1][1] + eb.y*mAR.m[0][1]; if(GREATER(t, t2)) return FALSE; // L = A1 x B2
t = Ty*mR1to0.m[0][0] - Tx*mR1to0.m[0][1]; t2 = ea.x*mAR.m[0][1] + ea.y*mAR.m[0][0] + eb.y*mAR.m[2][2] + eb.z*mAR.m[1][2]; if(GREATER(t, t2)) return FALSE; // L = A2 x B0
t = Ty*mR1to0.m[1][0] - Tx*mR1to0.m[1][1]; t2 = ea.x*mAR.m[1][1] + ea.y*mAR.m[1][0] + eb.x*mAR.m[2][2] + eb.z*mAR.m[0][2]; if(GREATER(t, t2)) return FALSE; // L = A2 x B1
t = Ty*mR1to0.m[2][0] - Tx*mR1to0.m[2][1]; t2 = ea.x*mAR.m[2][1] + ea.y*mAR.m[2][0] + eb.x*mAR.m[1][2] + eb.y*mAR.m[0][2]; if(GREATER(t, t2)) return FALSE; // L = A2 x B2
}
return TRUE;
}
//! A dedicated version when one box is constant
inline_ BOOL OBBCollider::BoxBoxOverlap(const Point& extents, const Point& center)
{
// Stats
mNbVolumeBVTests++;
float t,t2;
// Class I : A's basis vectors
float Tx = mTBoxToModel.x - center.x; t = extents.x + mBBx1; if(GREATER(Tx, t)) return FALSE;
float Ty = mTBoxToModel.y - center.y; t = extents.y + mBBy1; if(GREATER(Ty, t)) return FALSE;
float Tz = mTBoxToModel.z - center.z; t = extents.z + mBBz1; if(GREATER(Tz, t)) return FALSE;
// Class II : B's basis vectors
t = Tx*mRBoxToModel.m[0][0] + Ty*mRBoxToModel.m[0][1] + Tz*mRBoxToModel.m[0][2];
t2 = extents.x*mAR.m[0][0] + extents.y*mAR.m[0][1] + extents.z*mAR.m[0][2] + mBoxExtents.x;
if(GREATER(t, t2)) return FALSE;
t = Tx*mRBoxToModel.m[1][0] + Ty*mRBoxToModel.m[1][1] + Tz*mRBoxToModel.m[1][2];
t2 = extents.x*mAR.m[1][0] + extents.y*mAR.m[1][1] + extents.z*mAR.m[1][2] + mBoxExtents.y;
if(GREATER(t, t2)) return FALSE;
t = Tx*mRBoxToModel.m[2][0] + Ty*mRBoxToModel.m[2][1] + Tz*mRBoxToModel.m[2][2];
t2 = extents.x*mAR.m[2][0] + extents.y*mAR.m[2][1] + extents.z*mAR.m[2][2] + mBoxExtents.z;
if(GREATER(t, t2)) return FALSE;
// Class III : 9 cross products
// Cool trick: always perform the full test for first level, regardless of settings.
// That way pathological cases (such as the pencils scene) are quickly rejected anyway !
if(mFullBoxBoxTest || mNbVolumeBVTests==1)
{
t = Tz*mRBoxToModel.m[0][1] - Ty*mRBoxToModel.m[0][2]; t2 = extents.y*mAR.m[0][2] + extents.z*mAR.m[0][1] + mBB_1; if(GREATER(t, t2)) return FALSE; // L = A0 x B0
t = Tz*mRBoxToModel.m[1][1] - Ty*mRBoxToModel.m[1][2]; t2 = extents.y*mAR.m[1][2] + extents.z*mAR.m[1][1] + mBB_2; if(GREATER(t, t2)) return FALSE; // L = A0 x B1
t = Tz*mRBoxToModel.m[2][1] - Ty*mRBoxToModel.m[2][2]; t2 = extents.y*mAR.m[2][2] + extents.z*mAR.m[2][1] + mBB_3; if(GREATER(t, t2)) return FALSE; // L = A0 x B2
t = Tx*mRBoxToModel.m[0][2] - Tz*mRBoxToModel.m[0][0]; t2 = extents.x*mAR.m[0][2] + extents.z*mAR.m[0][0] + mBB_4; if(GREATER(t, t2)) return FALSE; // L = A1 x B0
t = Tx*mRBoxToModel.m[1][2] - Tz*mRBoxToModel.m[1][0]; t2 = extents.x*mAR.m[1][2] + extents.z*mAR.m[1][0] + mBB_5; if(GREATER(t, t2)) return FALSE; // L = A1 x B1
t = Tx*mRBoxToModel.m[2][2] - Tz*mRBoxToModel.m[2][0]; t2 = extents.x*mAR.m[2][2] + extents.z*mAR.m[2][0] + mBB_6; if(GREATER(t, t2)) return FALSE; // L = A1 x B2
t = Ty*mRBoxToModel.m[0][0] - Tx*mRBoxToModel.m[0][1]; t2 = extents.x*mAR.m[0][1] + extents.y*mAR.m[0][0] + mBB_7; if(GREATER(t, t2)) return FALSE; // L = A2 x B0
t = Ty*mRBoxToModel.m[1][0] - Tx*mRBoxToModel.m[1][1]; t2 = extents.x*mAR.m[1][1] + extents.y*mAR.m[1][0] + mBB_8; if(GREATER(t, t2)) return FALSE; // L = A2 x B1
t = Ty*mRBoxToModel.m[2][0] - Tx*mRBoxToModel.m[2][1]; t2 = extents.x*mAR.m[2][1] + extents.y*mAR.m[2][0] + mBB_9; if(GREATER(t, t2)) return FALSE; // L = A2 x B2
}
return TRUE;
}
//! A special version for 2 axis-aligned boxes
inline_ BOOL AABBCollider::AABBAABBOverlap(const Point& extents, const Point& center)
{
// Stats
mNbVolumeBVTests++;
float tx = mBox.mCenter.x - center.x; float ex = extents.x + mBox.mExtents.x; if(GREATER(tx, ex)) return FALSE;
float ty = mBox.mCenter.y - center.y; float ey = extents.y + mBox.mExtents.y; if(GREATER(ty, ey)) return FALSE;
float tz = mBox.mCenter.z - center.z; float ez = extents.z + mBox.mExtents.z; if(GREATER(tz, ez)) return FALSE;
return TRUE;
}