Merging math libraries

2 files changed, 241 insertions, 26 deletions

diff --git a/redist/linmath.c b/redist/linmath.c
index 60fbc21..ea44432 100644
--- a/redist/linmath.c
+++ b/redist/linmath.c
@@ -2,6 +2,7 @@
 
 #include "linmath.h"
 #include <math.h>
+#include <float.h>
 
 void cross3d( FLT * out, const FLT * a, const FLT * b )
 {
@@ -33,7 +34,7 @@ void scale3d( FLT * out, const FLT * a, FLT scalar )
 
 void normalize3d( FLT * out, const FLT * in )
 {
-	FLT r = 1./sqrtf( in[0] * in[0] + in[1] * in[1] + in[2] * in[2] );
+    FLT r = ((FLT)1.) / FLT_SQRT(in[0] * in[0] + in[1] * in[1] + in[2] * in[2]);
 	out[0] = in[0] * r;
 	out[1] = in[1] * r;
 	out[2] = in[2] * r;
@@ -65,7 +66,7 @@ void copy3d( FLT * out, const FLT * in )
 
 FLT magnitude3d( FLT * a )
 {
-	return sqrt( a[0]*a[0] + a[1]*a[1] + a[2]*a[2] );
+    return FLT_SQRT(a[0] * a[0] + a[1] * a[1] + a[2] * a[2]);
 }
 
 FLT anglebetween3d( FLT * a, FLT * b )
@@ -77,7 +78,7 @@ FLT anglebetween3d( FLT * a, FLT * b )
 	FLT dot = dot3d( a, b );
 	if( dot < -0.9999999 ) return LINMATHPI;
 	if( dot >  0.9999999 ) return 0;
-	return acos( dot );
+    return FLT_ACOS(dot);
 }
 
 /////////////////////////////////////QUATERNIONS//////////////////////////////////////////
@@ -106,12 +107,12 @@ void quatfromeuler( FLT * q, const FLT * euler )
 	FLT Y = euler[1]/2.0f; //pitch
 	FLT Z = euler[2]/2.0f; //yaw
 
-	FLT cx = cosf(X);
-	FLT sx = sinf(X);
-	FLT cy = cosf(Y);
-	FLT sy = sinf(Y);
-	FLT cz = cosf(Z);
-	FLT sz = sinf(Z);
+    FLT cx = FLT_COS(X);
+    FLT sx = FLT_SIN(X);
+    FLT cy = FLT_COS(Y);
+    FLT sy = FLT_SIN(Y);
+    FLT cz = FLT_COS(Z);
+    FLT sz = FLT_SIN(Z);
 
 	//Correct according to
 	//http://en.wikipedia.org/wiki/Conversion_between_MQuaternions_and_Euler_angles
@@ -125,9 +126,9 @@ void quatfromeuler( FLT * q, const FLT * euler )
 void quattoeuler( FLT * euler, const FLT * q )
 {
 	//According to http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles (Oct 26, 2009)
-	euler[0] = atan2( 2 * (q[0]*q[1] + q[2]*q[3]), 1 - 2 * (q[1]*q[1] + q[2]*q[2] ) );
-	euler[1] = asin( 2 * (q[0] *q[2] - q[3]*q[1] ) );
-	euler[2] = atan2( 2 * (q[0]*q[3] + q[1]*q[2]), 1 - 2 * (q[2]*q[2] + q[3]*q[3] ) );
+    euler[0] = FLT_ATAN2(2 * (q[0] * q[1] + q[2] * q[3]), 1 - 2 * (q[1] * q[1] + q[2] * q[2]));
+    euler[1] = FLT_ASIN(2 * (q[0] * q[2] - q[3] * q[1]));
+    euler[2] = FLT_ATAN2(2 * (q[0] * q[3] + q[1] * q[2]), 1 - 2 * (q[2] * q[2] + q[3] * q[3]));
 }
 
 void quatfromaxisangle( FLT * q, const FLT * axis, FLT radians )
@@ -135,8 +136,8 @@ void quatfromaxisangle( FLT * q, const FLT * axis, FLT radians )
 	FLT v[3];
 	normalize3d( v, axis );
 	
-	FLT sn = sin(radians/2.0f);
-	q[0] = cos(radians/2.0f);
+    FLT sn = FLT_SIN(radians / 2.0f);
+    q[0] = FLT_COS(radians / 2.0f);
 	q[1] = sn * v[0];
 	q[2] = sn * v[1];
 	q[3] = sn * v[2];
@@ -146,12 +147,12 @@ void quatfromaxisangle( FLT * q, const FLT * axis, FLT radians )
 
 FLT quatmagnitude( const FLT * q )
 {
-	return sqrt((q[0]*q[0])+(q[1]*q[1])+(q[2]*q[2])+(q[3]*q[3]));
+    return FLT_SQRT((q[0] * q[0]) + (q[1] * q[1]) + (q[2] * q[2]) + (q[3] * q[3]));
 }
 
 FLT quatinvsqmagnitude( const FLT * q )
 {
-	return 1./((q[0]*q[0])+(q[1]*q[1])+(q[2]*q[2])+(q[3]*q[3]));
+	return ((FLT)1.)/((q[0]*q[0])+(q[1]*q[1])+(q[2]*q[2])+(q[3]*q[3]));
 }
 
 
@@ -296,13 +297,13 @@ void quatslerp( FLT * q, const FLT * qa, const FLT * qb, FLT t )
 	if ( 1 - (cosTheta*cosTheta) <= 0 )
 		sinTheta = 0;
 	else
-		sinTheta = sqrt(1 - (cosTheta*cosTheta));
+        sinTheta = FLT_SQRT(1 - (cosTheta*cosTheta));
 
-	FLT Theta = acos(cosTheta); //Theta is half the angle between the 2 MQuaternions
+    FLT Theta = FLT_ACOS(cosTheta); //Theta is half the angle between the 2 MQuaternions
 
-	if(fabs(Theta) < DEFAULT_EPSILON )
+    if (FLT_FABS(Theta) < DEFAULT_EPSILON)
 		quatcopy( q, qa );
-	else if(fabs(sinTheta) < DEFAULT_EPSILON )
+    else if (FLT_FABS(sinTheta) < DEFAULT_EPSILON)
 	{
 		quatadd( q, qa, qb );
 		quatscale( q, q, 0.5 );
@@ -311,10 +312,10 @@ void quatslerp( FLT * q, const FLT * qa, const FLT * qb, FLT t )
 	{
 		FLT aside[4];
 		FLT bside[4];
-		quatscale( bside, qb, sin( t * Theta ) );
-		quatscale( aside, qa, sin((1-t)*Theta) );
+        quatscale( bside, qb, FLT_SIN(t * Theta));
+        quatscale( aside, qa, FLT_SIN((1 - t)*Theta));
 		quatadd( q, aside, bside );
-		quatscale( q, q, 1./sinTheta );
+		quatscale( q, q, ((FLT)1.)/sinTheta );
 	}
 }
 
@@ -338,4 +339,176 @@ void quatrotatevector( FLT * vec3out, const FLT * quat, const FLT * vec3in )
 }
 
 
+// Matrix Stuff
+
+Matrix3x3 inverseM33(const Matrix3x3 mat)
+{
+    Matrix3x3 newMat;
+    for (int a = 0; a < 3; a++)
+    {
+        for (int b = 0; b < 3; b++)
+        {
+            newMat.val[a][b] = mat.val[a][b];
+        }
+    }
+
+    for (int i = 0; i < 3; i++)
+    {
+        for (int j = i + 1; j < 3; j++)
+        {
+            FLT tmp = newMat.val[i][j];
+            newMat.val[i][j] = newMat.val[j][i];
+            newMat.val[j][i] = tmp;
+        }
+    }
+
+    return newMat;
+}
+
+/////////////////////////////////////Matrix Rotations////////////////////////////////////
+//Originally from Stack Overflow 
+//Under cc by-sa 3.0
+//  http://stackoverflow.com/questions/23166898/efficient-way-to-calculate-a-3x3-rotation-matrix-from-the-rotation-defined-by-tw
+// Copyright 2014 by Campbell Barton
+// Copyright 2017 by Michael Turvey
+
+/**
+* Calculate a rotation matrix from 2 normalized vectors.
+*
+* v1 and v2 must be unit length.
+*/
+void rotation_between_vecs_to_mat3(FLT m[3][3], const FLT v1[3], const FLT v2[3])
+{
+    FLT axis[3];
+    /* avoid calculating the angle */
+    FLT angle_sin;
+    FLT angle_cos;
+
+    cross3d(axis, v1, v2);
+
+    angle_sin = normalize_v3(axis);
+    angle_cos = dot3d(v1, v2);
+
+    if (angle_sin > FLT_EPSILON) {
+    axis_calc:
+        axis_angle_normalized_to_mat3_ex(m, axis, angle_sin, angle_cos);
+    }
+    else {
+        /* Degenerate (co-linear) vectors */
+        if (angle_cos > 0.0f) {
+            /* Same vectors, zero rotation... */
+            unit_m3(m);
+        }
+        else {
+            /* Colinear but opposed vectors, 180 rotation... */
+            get_orthogonal_vector(axis, v1);
+            normalize_v3(axis);
+            angle_sin = 0.0f;  /* sin(M_PI) */
+            angle_cos = -1.0f;  /* cos(M_PI) */
+            goto axis_calc;
+        }
+    }
+}
+
+void get_orthogonal_vector(FLT out[3], const FLT in[3])
+{
+#ifdef USE_DOUBLE
+    const FLT x = fabs(in[0]);
+    const FLT y = fabs(in[1]);
+    const FLT z = fabs(in[2]);
+#else
+    const FLT x = fabsf(in[0]);
+    const FLT y = fabsf(in[1]);
+    const FLT z = fabsf(in[2]);
+#endif
+
+    if (x > y && x > z)
+    {
+        // x is dominant
+        out[0] = -in[1] - in[2];
+        out[1] = in[0];
+        out[2] = in[0];
+    }
+    else if (y > z)
+    {
+        // y is dominant
+        out[0] = in[1];
+        out[1] = -in[0] - in[2];
+        out[2] = in[1];
+    }
+    else
+    {
+        // z is dominant
+        out[0] = in[2];
+        out[1] = in[2];
+        out[2] = -in[0] - in[1];
+    }
+}
+
+void unit_m3(FLT mat[3][3])
+{
+    mat[0][0] = 1;
+    mat[0][1] = 0;
+    mat[0][2] = 0;
+    mat[1][0] = 0;
+    mat[1][1] = 1;
+    mat[1][2] = 0;
+    mat[2][0] = 0;
+    mat[2][1] = 0;
+    mat[2][2] = 1;
+}
+
+
+FLT normalize_v3(FLT vect[3])
+{
+    FLT distance = dot3d(vect, vect);
+
+    if (distance < 1.0e-35f)
+    {
+        // distance is too short, just go to zero.
+        vect[0] = 0;
+        vect[1] = 0;
+        vect[2] = 0;
+        distance = 0;
+    }
+    else
+    {
+        distance = FLT_SQRT((FLT)distance);
+        scale3d(vect, vect, 1.0f / distance);
+    }
+
+    return distance;
+}
+
+/* axis must be unit length */
+void axis_angle_normalized_to_mat3_ex(
+    FLT mat[3][3], const FLT axis[3],
+    const FLT angle_sin, const FLT angle_cos)
+{
+    FLT nsi[3], ico;
+    FLT n_00, n_01, n_11, n_02, n_12, n_22;
+
+    ico = (1.0f - angle_cos);
+    nsi[0] = axis[0] * angle_sin;
+    nsi[1] = axis[1] * angle_sin;
+    nsi[2] = axis[2] * angle_sin;
+
+    n_00 = (axis[0] * axis[0]) * ico;
+    n_01 = (axis[0] * axis[1]) * ico;
+    n_11 = (axis[1] * axis[1]) * ico;
+    n_02 = (axis[0] * axis[2]) * ico;
+    n_12 = (axis[1] * axis[2]) * ico;
+    n_22 = (axis[2] * axis[2]) * ico;
+
+    mat[0][0] = n_00 + angle_cos;
+    mat[0][1] = n_01 + nsi[2];
+    mat[0][2] = n_02 - nsi[1];
+    mat[1][0] = n_01 - nsi[2];
+    mat[1][1] = n_11 + angle_cos;
+    mat[1][2] = n_12 + nsi[0];
+    mat[2][0] = n_02 + nsi[1];
+    mat[2][1] = n_12 - nsi[0];
+    mat[2][2] = n_22 + angle_cos;
+}
+
 
diff --git a/redist/linmath.h b/redist/linmath.h
index 5cc7b7d..530d291 100644
--- a/redist/linmath.h
+++ b/redist/linmath.h
@@ -10,14 +10,37 @@
 #define PFTHREE(x) x[0], x[1], x[2]
 #define PFFOUR(x) x[0], x[1], x[2], x[3]
 
-#define LINMATHPI 3.141592653589
+#define LINMATHPI ((FLT)3.141592653589)
+
+//uncomment the following line to use double precision instead of single precision.
+//#define USE_DOUBLE
+
+#ifdef USE_DOUBLE
+
+#define FLT double
+#define FLT_SQRT sqrt
+#define FLT_SIN  sin
+#define FLT_COS  cos
+#define FLT_ACOS  acos
+#define FLT_ASIN  asin
+#define FLT_ATAN2  atan2
+#define FLT_FABS fabs
+
+#else
 
-//If you want, you can define FLT to be double for double precision.
-#ifndef FLT
 #define FLT float
+#define FLT_SQRT sqrtf
+#define FLT_SIN  sinf
+#define FLT_COS  cosf
+#define FLT_ACOS  acosf
+#define FLT_ASIN  asinf
+#define FLT_ATAN2  atan2f
+#define FLT_FABS fabsf
+
 #endif
 
 
+
 //NOTE: Inputs may never be output with cross product.
 void cross3d( FLT * out, const FLT * a, const FLT * b );
 
@@ -64,6 +87,25 @@ void quatoddproduct( FLT * outvec3, FLT * qa, FLT * qb );
 void quatslerp( FLT * q, const FLT * qa, const FLT * qb, FLT t );
 void quatrotatevector( FLT * vec3out, const FLT * quat, const FLT * vec3in );
 
+// Matrix Stuff
+
+typedef struct
+{
+    // row, column, (0,0) in upper left
+    FLT val[3][3];
+} Matrix3x3;
+
+Matrix3x3 inverseM33(const Matrix3x3 mat);
+void get_orthogonal_vector(FLT out[3], const FLT in[3]);
+void rotation_between_vecs_to_mat3(FLT m[3][3], const FLT v1[3], const FLT v2[3]);
+void unit_m3(FLT m[3][3]);
+FLT normalize_v3(FLT n[3]);
+void axis_angle_normalized_to_mat3_ex(
+    FLT mat[3][3],
+    const FLT axis[3],
+    const FLT angle_sin,
+    const FLT angle_cos);
+
 
 #endif