From 765bf1623299e81f5f95b78a78e7d66997e4ad0c Mon Sep 17 00:00:00 2001 From: cnlohr Date: Thu, 9 Mar 2017 20:00:42 -0500 Subject: Fix wrong quat functions + Add matrix->quat conversion. --- redist/linmath.c | 58 ++++++++++++++++++++++++++++++++++++++++++++------------ redist/linmath.h | 5 +++-- 2 files changed, 49 insertions(+), 14 deletions(-) (limited to 'redist') diff --git a/redist/linmath.c b/redist/linmath.c index 1c5c25b..d76fbba 100644 --- a/redist/linmath.c +++ b/redist/linmath.c @@ -152,7 +152,7 @@ FLT quatmagnitude( const FLT * q ) FLT quatinvsqmagnitude( const FLT * q ) { - return ((FLT)1.)/((q[0]*q[0])+(q[1]*q[1])+(q[2]*q[2])+(q[3]*q[3])); + return ((FLT)1.)/FLT_SQRT((q[0]*q[0])+(q[1]*q[1])+(q[2]*q[2])+(q[3]*q[3])); } @@ -168,17 +168,17 @@ void quattomatrix(FLT * matrix44, const FLT * qin) quatnormalize(q, qin); //Reduced calulation for speed - FLT xx = 2 * q[0] * q[0]; - FLT xy = 2 * q[0] * q[1]; - FLT xz = 2 * q[0] * q[2]; - FLT xw = 2 * q[0] * q[3]; + FLT xx = 2 * q[1] * q[1]; + FLT xy = 2 * q[1] * q[2]; + FLT xz = 2 * q[1] * q[3]; + FLT xw = 2 * q[1] * q[0]; - FLT yy = 2 * q[1] * q[1]; - FLT yz = 2 * q[1] * q[2]; - FLT yw = 2 * q[1] * q[3]; + FLT yy = 2 * q[2] * q[2]; + FLT yz = 2 * q[2] * q[3]; + FLT yw = 2 * q[2] * q[0]; - FLT zz = 2 * q[2] * q[2]; - FLT zw = 2 * q[2] * q[3]; + FLT zz = 2 * q[3] * q[3]; + FLT zw = 2 * q[3] * q[0]; //opengl major matrix44[0] = 1 - yy - zz; @@ -202,6 +202,40 @@ void quattomatrix(FLT * matrix44, const FLT * qin) matrix44[15] = 1; } + +void quatfrommatrix( FLT * q, const FLT * matrix44 ) +{ + //Algorithm from http://www.euclideanspace.com/maths/geometry/rotations/conversions/matrixToQuaternion/ + float tr = matrix44[0] + matrix44[5] + matrix44[10]; + + if (tr > 0) { + float S = sqrt(tr+1.0) * 2; // S=4*qw + q[0] = 0.25 * S; + q[1] = (matrix44[9] - matrix44[6]) / S; + q[2] = (matrix44[2] - matrix44[8]) / S; + q[3] = (matrix44[4] - matrix44[1]) / S; + } else if ((matrix44[0] > matrix44[5])&(matrix44[0] > matrix44[10])) { + float S = sqrt(1.0 + matrix44[0] - matrix44[5] - matrix44[10]) * 2; // S=4*qx + q[0] = (matrix44[9] - matrix44[6]) / S; + q[1] = 0.25 * S; + q[2] = (matrix44[1] + matrix44[4]) / S; + q[3] = (matrix44[2] + matrix44[8]) / S; + } else if (matrix44[5] > matrix44[10]) { + float S = sqrt(1.0 + matrix44[5] - matrix44[0] - matrix44[10]) * 2; // S=4*qy + q[0] = (matrix44[2] - matrix44[8]) / S; + q[1] = (matrix44[1] + matrix44[4]) / S; + q[2] = 0.25 * S; + q[3] = (matrix44[6] + matrix44[9]) / S; + } else { + float S = sqrt(1.0 + matrix44[10] - matrix44[0] - matrix44[5]) * 2; // S=4*qz + q[0] = (matrix44[4] - matrix44[1]) / S; + q[1] = (matrix44[2] + matrix44[8]) / S; + q[2] = (matrix44[6] + matrix44[9]) / S; + q[3] = 0.25 * S; + } +} + + void quattomatrix33(FLT * matrix33, const FLT * qin) { FLT q[4]; @@ -270,8 +304,8 @@ void quatrotateabout( FLT * qout, const FLT * a, const FLT * b ) FLT q1[4]; FLT q2[4]; - quatnormalize( q1, a ); - quatnormalize( q2, b ); + //quatnormalize( q1, a ); + //quatnormalize( q2, b ); qout[0] = (q1[0]*q2[0])-(q1[1]*q2[1])-(q1[2]*q2[2])-(q1[3]*q2[3]); qout[1] = (q1[0]*q2[1])+(q1[1]*q2[0])+(q1[2]*q2[3])-(q1[3]*q2[2]); diff --git a/redist/linmath.h b/redist/linmath.h index caec281..ec20534 100644 --- a/redist/linmath.h +++ b/redist/linmath.h @@ -7,8 +7,8 @@ #define DEFAULT_EPSILON 0.001 //For printf -#define PFTHREE(x) x[0], x[1], x[2] -#define PFFOUR(x) x[0], x[1], x[2], x[3] +#define PFTHREE(x) (x)[0], (x)[1], (x)[2] +#define PFFOUR(x) (x)[0], (x)[1], (x)[2], (x)[3] #define LINMATHPI ((FLT)3.141592653589) @@ -76,6 +76,7 @@ FLT quatmagnitude( const FLT * q ); FLT quatinvsqmagnitude( const FLT * q ); void quatnormalize( FLT * qout, const FLT * qin ); //Safe for in to be same as out. void quattomatrix( FLT * matrix44, const FLT * q ); +void quatfrommatrix( FLT * q, const FLT * matrix44 ); void quatgetconjugate( FLT * qout, const FLT * qin ); void quatgetreciprocal( FLT * qout, const FLT * qin ); void quatsub( FLT * qout, const FLT * a, const FLT * b ); -- cgit v1.2.3