diff --git a/src/main/java/pythagoras/d/AbstractMatrix3.java b/src/main/java/pythagoras/d/AbstractMatrix3.java
new file mode 100644
index 0000000..7697479
--- /dev/null
+++ b/src/main/java/pythagoras/d/AbstractMatrix3.java
@@ -0,0 +1,346 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import java.nio.DoubleBuffer;
+
+import pythagoras.util.Platform;
+import pythagoras.util.SingularMatrixException;
+
+/**
+ * Provides most of the implementation of {@link IMatrix3}, obtaining only the components from the
+ * derived class.
+ */
+public abstract class AbstractMatrix3 implements IMatrix3
+{
+ @Override // from IVector3
+ public Matrix3 transpose () {
+ return transpose(new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 transpose (Matrix3 result) {
+ return result.set(
+ m00(), m01(), m02(),
+ m10(), m11(), m12(),
+ m20(), m21(), m22());
+ }
+
+ @Override // from IVector3
+ public Matrix3 mult (IMatrix3 other) {
+ return mult(other, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 mult (IMatrix3 other, Matrix3 result) {
+ double m00 = m00(), m01 = m01(), m02 = m02();
+ double m10 = m10(), m11 = m11(), m12 = m12();
+ double m20 = m20(), m21 = m21(), m22 = m22();
+ double om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ double om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ double om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00*om00 + m10*om01 + m20*om02,
+ m00*om10 + m10*om11 + m20*om12,
+ m00*om20 + m10*om21 + m20*om22,
+
+ m01*om00 + m11*om01 + m21*om02,
+ m01*om10 + m11*om11 + m21*om12,
+ m01*om20 + m11*om21 + m21*om22,
+
+ m02*om00 + m12*om01 + m22*om02,
+ m02*om10 + m12*om11 + m22*om12,
+ m02*om20 + m12*om21 + m22*om22);
+ }
+
+ @Override // from IVector3
+ public boolean isAffine () {
+ return (m02() == 0f && m12() == 0f && m22() == 1f);
+ }
+
+ @Override // from IVector3
+ public Matrix3 multAffine (IMatrix3 other) {
+ return multAffine(other, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 multAffine (IMatrix3 other, Matrix3 result) {
+ double m00 = m00(), m01 = m01(), m02 = m02();
+ double m10 = m10(), m11 = m11(), m12 = m12();
+ double m20 = m20(), m21 = m21(), m22 = m22();
+ double om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ double om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ double om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00*om00 + m10*om01,
+ m00*om10 + m10*om11,
+ m00*om20 + m10*om21 + m20,
+
+ m01*om00 + m11*om01,
+ m01*om10 + m11*om11,
+ m01*om20 + m11*om21 + m21,
+
+ 0f, 0f, 1f);
+ }
+
+ @Override // from IVector3
+ public Matrix3 invert () {
+ return invert(new Matrix3());
+ }
+
+ /**
+ * Inverts this matrix and places the result in the given object. This code is based on the
+ * examples in the Matrix and
+ * Quaternion FAQ.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ public Matrix3 invert (Matrix3 result) throws SingularMatrixException {
+ double m00 = m00(), m01 = m01(), m02 = m02();
+ double m10 = m10(), m11 = m11(), m12 = m12();
+ double m20 = m20(), m21 = m21(), m22 = m22();
+ // compute the determinant, storing the subdeterminants for later use
+ double sd00 = m11*m22 - m21*m12;
+ double sd10 = m01*m22 - m21*m02;
+ double sd20 = m01*m12 - m11*m02;
+ double det = m00*sd00 + m20*sd20 - m10*sd10;
+ if (Math.abs(det) == 0f) {
+ // determinant is zero; matrix is not invertible
+ throw new SingularMatrixException(this.toString());
+ }
+ double rdet = 1f / det;
+ return result.set(
+ +sd00 * rdet,
+ -(m10*m22 - m20*m12) * rdet,
+ +(m10*m21 - m20*m11) * rdet,
+
+ -sd10 * rdet,
+ +(m00*m22 - m20*m02) * rdet,
+ -(m00*m21 - m20*m01) * rdet,
+
+ +sd20 * rdet,
+ -(m00*m12 - m10*m02) * rdet,
+ +(m00*m11 - m10*m01) * rdet);
+ }
+
+ @Override // from IVector3
+ public Matrix3 invertAffine () {
+ return invertAffine(new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 invertAffine (Matrix3 result) throws SingularMatrixException {
+ double m00 = m00(), m01 = m01(), m02 = m02();
+ double m10 = m10(), m11 = m11(), m12 = m12();
+ double m20 = m20(), m21 = m21(), m22 = m22();
+ // compute the determinant, storing the subdeterminants for later use
+ double det = m00*m11 - m10*m01;
+ if (Math.abs(det) == 0f) {
+ // determinant is zero; matrix is not invertible
+ throw new SingularMatrixException(this.toString());
+ }
+ double rdet = 1f / det;
+ return result.set(
+ +m11 * rdet,
+ -m10 * rdet,
+ +(m10*m21 - m20*m11) * rdet,
+
+ -m01 * rdet,
+ +m00 * rdet,
+ -(m00*m21 - m20*m01) * rdet,
+
+ 0f, 0f, 1f);
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerp (IMatrix3 other, double t) {
+ return lerp(other, t, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerp (IMatrix3 other, double t, Matrix3 result) {
+ double m00 = m00(), m01 = m01(), m02 = m02();
+ double m10 = m10(), m11 = m11(), m12 = m12();
+ double m20 = m20(), m21 = m21(), m22 = m22();
+ double om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ double om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ double om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00 + t*(om00 - m00),
+ m10 + t*(om10 - m10),
+ m20 + t*(om20 - m20),
+
+ m01 + t*(om01 - m01),
+ m11 + t*(om11 - m11),
+ m21 + t*(om21 - m21),
+
+ m02 + t*(om02 - m02),
+ m12 + t*(om12 - m12),
+ m22 + t*(om22 - m22));
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerpAffine (IMatrix3 other, double t) {
+ return lerpAffine(other, t, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerpAffine (IMatrix3 other, double t, Matrix3 result) {
+ double m00 = m00(), m01 = m01(), m02 = m02();
+ double m10 = m10(), m11 = m11(), m12 = m12();
+ double m20 = m20(), m21 = m21(), m22 = m22();
+ double om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ double om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ double om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00 + t*(om00 - m00),
+ m10 + t*(om10 - m10),
+ m20 + t*(om20 - m20),
+
+ m01 + t*(om01 - m01),
+ m11 + t*(om11 - m11),
+ m21 + t*(om21 - m21),
+
+ 0f, 0f, 1f);
+ }
+
+ @Override // from IVector3
+ public DoubleBuffer get (DoubleBuffer buf) {
+ buf.put(m00()).put(m01()).put(m02());
+ buf.put(m10()).put(m11()).put(m12());
+ buf.put(m20()).put(m21()).put(m22());
+ return buf;
+ }
+
+ @Override // from IVector3
+ public Vector3 transformLocal (Vector3 vector) {
+ return transform(vector, vector);
+ }
+
+ @Override // from IVector3
+ public Vector3 transform (IVector3 vector) {
+ return transform(vector, new Vector3());
+ }
+
+ @Override // from IVector3
+ public Vector3 transform (IVector3 vector, Vector3 result) {
+ double vx = vector.x(), vy = vector.y(), vz = vector.z();
+ return result.set(
+ m00()*vx + m10()*vy + m20()*vz,
+ m01()*vx + m11()*vy + m21()*vz,
+ m02()*vx + m12()*vy + m22()*vz);
+ }
+
+ @Override // from IVector3
+ public Vector transformPointLocal (Vector point) {
+ return transformPoint(point, point);
+ }
+
+ @Override // from IVector3
+ public Vector transformPoint (IVector point) {
+ return transformPoint(point, new Vector());
+ }
+
+ @Override // from IVector3
+ public Vector transformPoint (IVector point, Vector result) {
+ double px = point.x(), py = point.y();
+ return result.set(m00()*px + m10()*py + m20(), m01()*px + m11()*py + m21());
+ }
+
+ @Override // from IVector3
+ public Vector transformVectorLocal (Vector vector) {
+ return transformVector(vector, vector);
+ }
+
+ @Override // from IVector3
+ public Vector transformVector (IVector vector) {
+ return transformVector(vector, new Vector());
+ }
+
+ @Override // from IVector3
+ public Vector transformVector (IVector vector, Vector result) {
+ double vx = vector.x(), vy = vector.y();
+ return result.set(m00()*vx + m10()*vy, m01()*vx + m11()*vy);
+ }
+
+ @Override // from IVector3
+ public double extractRotation () {
+ // start with the contents of the upper 2x2 portion of the matrix
+ double n00 = m00(), n10 = m10();
+ double n01 = m01(), n11 = m11();
+ for (int ii = 0; ii < 10; ii++) {
+ // store the results of the previous iteration
+ double o00 = n00, o10 = n10;
+ double o01 = n01, o11 = n11;
+
+ // compute average of the matrix with its inverse transpose
+ double det = o00*o11 - o10*o01;
+ if (Math.abs(det) == 0f) {
+ // determinant is zero; matrix is not invertible
+ throw new SingularMatrixException(this.toString());
+ }
+ double hrdet = 0.5f / det;
+ n00 = +o11 * hrdet + o00*0.5f;
+ n10 = -o01 * hrdet + o10*0.5f;
+
+ n01 = -o10 * hrdet + o01*0.5f;
+ n11 = +o00 * hrdet + o11*0.5f;
+
+ // compute the difference; if it's small enough, we're done
+ double d00 = n00 - o00, d10 = n10 - o10;
+ double d01 = n01 - o01, d11 = n11 - o11;
+ if (d00*d00 + d10*d10 + d01*d01 + d11*d11 < MathUtil.EPSILON) {
+ break;
+ }
+ }
+ // now that we have a nice orthogonal matrix, we can extract the rotation
+ return Math.atan2(n01, n00);
+ }
+
+ @Override // from IVector3
+ public Vector extractScale () {
+ return extractScale(new Vector());
+ }
+
+ @Override // from IVector3
+ public Vector extractScale (Vector result) {
+ double m00 = m00(), m01 = m01(), m10 = m10(), m11 = m11();
+ return result.set(
+ Math.sqrt(m00*m00 + m01*m01),
+ Math.sqrt(m10*m10 + m11*m11));
+ }
+
+ @Override // from IVector3
+ public double approximateUniformScale () {
+ double cp = m00()*m11() - m01()*m10();
+ return (cp < 0f) ? -Math.sqrt(-cp) : Math.sqrt(cp);
+ }
+
+ @Override
+ public String toString () {
+ return "[[" + m00() + ", " + m10() + ", " + m20() + "], " +
+ "[" + m01() + ", " + m11() + ", " + m21() + "], " +
+ "[" + m02() + ", " + m12() + ", " + m22() + "]]";
+ }
+
+ @Override
+ public int hashCode () {
+ return Platform.hashCode(m00()) ^ Platform.hashCode(m10()) ^ Platform.hashCode(m20()) ^
+ Platform.hashCode(m01()) ^ Platform.hashCode(m11()) ^ Platform.hashCode(m21()) ^
+ Platform.hashCode(m02()) ^ Platform.hashCode(m12()) ^ Platform.hashCode(m22());
+ }
+
+ @Override
+ public boolean equals (Object other) {
+ if (!(other instanceof AbstractMatrix3)) {
+ return false;
+ }
+ AbstractMatrix3 omat = (AbstractMatrix3)other;
+ return
+ m00() == omat.m00() && m10() == omat.m10() && m20() == omat.m20() &&
+ m01() == omat.m01() && m11() == omat.m11() && m21() == omat.m21() &&
+ m02() == omat.m02() && m12() == omat.m12() && m22() == omat.m22();
+ }
+}
diff --git a/src/main/java/pythagoras/d/AbstractVector3.java b/src/main/java/pythagoras/d/AbstractVector3.java
new file mode 100644
index 0000000..d3b8d8c
--- /dev/null
+++ b/src/main/java/pythagoras/d/AbstractVector3.java
@@ -0,0 +1,204 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import java.nio.DoubleBuffer;
+
+import pythagoras.util.Platform;
+
+/**
+ * Provides most of the implementation of {@link IVector3}, obtaining only x, y and z from the
+ * derived class.
+ */
+public abstract class AbstractVector3 implements IVector3
+{
+ @Override // from interface IVector3
+ public double dot (IVector3 other) {
+ return x()*other.x() + y()*other.y() + z()*other.z();
+ }
+
+ @Override // from interface IVector3
+ public Vector3 cross (IVector3 other) {
+ return cross(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 cross (IVector3 other, Vector3 result) {
+ double x = x(), y = y(), z = z();
+ double ox = other.x(), oy = other.y(), oz = other.z();
+ return result.set(y*oz - z*oy, z*ox - x*oz, x*oy - y*ox);
+ }
+
+ @Override // from interface IVector3
+ public double triple (IVector3 b, IVector3 c) {
+ double bx = b.x(), by = b.y(), bz = b.z();
+ double cx = c.x(), cy = c.y(), cz = c.z();
+ return x()*(by*cz - bz*cy) + y()*(bz*cx - bx*cz) + z()*(bx*cy - by*cx);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 negate () {
+ return negate(new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 negate (Vector3 result) {
+ return result.set(-x(), -y(), -z());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 normalize () {
+ return normalize(new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 normalize (Vector3 result) {
+ return mult(1f / length(), result);
+ }
+
+ @Override // from interface IVector3
+ public double angle (IVector3 other) {
+ return Math.acos(dot(other) / (length() * other.length()));
+ }
+
+ @Override // from interface IVector3
+ public double length () {
+ return Math.sqrt(lengthSquared());
+ }
+
+ @Override // from interface IVector3
+ public double lengthSquared () {
+ double x = x(), y = y(), z = z();
+ return (x*x + y*y + z*z);
+ }
+
+ @Override // from interface IVector3
+ public double distance (IVector3 other) {
+ return Math.sqrt(distanceSquared(other));
+ }
+
+ @Override // from interface IVector3
+ public double distanceSquared (IVector3 other) {
+ double dx = x() - other.x(), dy = y() - other.y(), dz = z() - other.z();
+ return dx*dx + dy*dy + dz*dz;
+ }
+
+ @Override // from interface IVector3
+ public double manhattanDistance (IVector3 other) {
+ return Math.abs(x() - other.x()) + Math.abs(y() - other.y()) + Math.abs(z() - other.z());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (double v) {
+ return mult(v, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (double v, Vector3 result) {
+ return result.set(x()*v, y()*v, z()*v);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (IVector3 other) {
+ return mult(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (IVector3 other, Vector3 result) {
+ return result.set(x()*other.x(), y()*other.y(), z()*other.z());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (IVector3 other) {
+ return add(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (IVector3 other, Vector3 result) {
+ return add(other.x(), other.y(), other.z(), result);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 subtract (IVector3 other) {
+ return subtract(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 subtract (IVector3 other, Vector3 result) {
+ return add(-other.x(), -other.y(), -other.z(), result);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (double x, double y, double z) {
+ return add(x, y, z, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (double x, double y, double z, Vector3 result) {
+ return result.set(x() + x, y() + y, z() + z);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 addScaled (IVector3 other, double v) {
+ return addScaled(other, v, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 addScaled (IVector3 other, double v, Vector3 result) {
+ return result.set(x() + other.x()*v, y() + other.y()*v, z() + other.z()*v);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 lerp (IVector3 other, double t) {
+ return lerp(other, t, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 lerp (IVector3 other, double t, Vector3 result) {
+ double x = x(), y = y(), z = z();
+ return result.set(x + t*(other.x() - x), y + t*(other.y() - y), z + t*(other.z() - z));
+ }
+
+ @Override // from interface IVector3
+ public double get (int idx) {
+ switch (idx) {
+ case 0: return x();
+ case 1: return y();
+ case 2: return z();
+ }
+ throw new IndexOutOfBoundsException(String.valueOf(idx));
+ }
+
+ @Override // from interface IVector3
+ public void get (double[] values) {
+ values[0] = x();
+ values[1] = y();
+ values[2] = z();
+ }
+
+ @Override // from interface IVector3
+ public DoubleBuffer get (DoubleBuffer buf) {
+ return buf.put(x()).put(y()).put(z());
+ }
+
+ @Override
+ public String toString () {
+ return "[" + x() + ", " + y() + ", " + z() + "]";
+ }
+
+ @Override
+ public int hashCode () {
+ return Platform.hashCode(x()) ^ Platform.hashCode(y()) ^ Platform.hashCode(z());
+ }
+
+ @Override
+ public boolean equals (Object other) {
+ if (!(other instanceof AbstractVector3)) {
+ return false;
+ }
+ AbstractVector3 ovec = (AbstractVector3)other;
+ return (x() == ovec.x() && y() == ovec.y() && z() == ovec.z());
+ }
+}
diff --git a/src/main/java/pythagoras/d/IMatrix3.java b/src/main/java/pythagoras/d/IMatrix3.java
new file mode 100644
index 0000000..403cc34
--- /dev/null
+++ b/src/main/java/pythagoras/d/IMatrix3.java
@@ -0,0 +1,250 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import java.nio.DoubleBuffer;
+
+import pythagoras.util.SingularMatrixException;
+
+/**
+ * Provides read-only access to a {@link Matrix3}.
+ */
+interface IMatrix3
+{
+ /** Returns the (0,0)th component of the matrix. */
+ double m00 ();
+
+ /** Returns the (1,0)th component of the matrix. */
+ double m10 ();
+
+ /** Returns the (2,0)th component of the matrix. */
+ double m20 ();
+
+ /** Returns the (0,1)th component of the matrix. */
+ double m01 ();
+
+ /** Returns the (1,1)th component of the matrix. */
+ double m11 ();
+
+ /** Returns the (2,1)th component of the matrix. */
+ double m21 ();
+
+ /** Returns the (0,2)th component of the matrix. */
+ double m02 ();
+
+ /** Returns the (1,2)th component of the matrix. */
+ double m12 ();
+
+ /** Returns the (2,2)th component of the matrix. */
+ double m22 ();
+
+ /**
+ * Transposes this matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 transpose ();
+
+ /**
+ * Transposes this matrix, storing the result in the provided object.
+ *
+ * @return the result matrix, for chaining.
+ */
+ Matrix3 transpose (Matrix3 result);
+
+ /**
+ * Multiplies this matrix by another.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 mult (IMatrix3 other);
+
+ /**
+ * Multiplies this matrix by another and stores the result in the object provided.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 mult (IMatrix3 other, Matrix3 result);
+
+ /**
+ * Determines whether this matrix represents an affine transformation.
+ */
+ boolean isAffine ();
+
+ /**
+ * Multiplies this matrix by another, treating the matrices as affine.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 multAffine (IMatrix3 other);
+
+ /**
+ * Multiplies this matrix by another, treating the matrices as affine, and stores the result
+ * in the object provided.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 multAffine (IMatrix3 other, Matrix3 result);
+
+ /**
+ * Inverts this matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 invert ();
+
+ /**
+ * Inverts this matrix and places the result in the given object. This code is based on the
+ * examples in the Matrix and
+ * Quaternion FAQ.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 invert (Matrix3 result) throws SingularMatrixException;
+
+ /**
+ * Inverts this matrix as an affine matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 invertAffine ();
+
+ /**
+ * Inverts this matrix as an affine matrix and places the result in the given object.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 invertAffine (Matrix3 result) throws SingularMatrixException;
+
+ /**
+ * Linearly interpolates between this and the specified other matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 lerp (IMatrix3 other, double t);
+
+ /**
+ * Linearly interpolates between this and the specified other matrix, placing the result in
+ * the object provided.
+ *
+ * @return a reference to the result object, for chaining.
+ */
+ Matrix3 lerp (IMatrix3 other, double t, Matrix3 result);
+
+ /**
+ * Linearly interpolates between this and the specified other matrix, treating the matrices as
+ * affine.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 lerpAffine (IMatrix3 other, double t);
+
+ /**
+ * Linearly interpolates between this and the specified other matrix (treating the matrices as
+ * affine), placing the result in the object provided.
+ *
+ * @return a reference to the result object, for chaining.
+ */
+ Matrix3 lerpAffine (IMatrix3 other, double t, Matrix3 result);
+
+ /**
+ * Places the contents of this matrix into the given buffer in the standard OpenGL order.
+ *
+ * @return a reference to the buffer, for chaining.
+ */
+ DoubleBuffer get (DoubleBuffer buf);
+
+ /**
+ * Transforms a vector in-place by the inner 3x3 part of this matrix.
+ *
+ * @return a reference to the vector, for chaining.
+ */
+ Vector3 transformLocal (Vector3 vector);
+
+ /**
+ * Transforms a vector by this matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 transform (IVector3 vector);
+
+ /**
+ * Transforms a vector by this matrix and places the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 transform (IVector3 vector, Vector3 result);
+
+ /**
+ * Transforms a point in-place by this matrix.
+ *
+ * @return a reference to the point, for chaining.
+ */
+ Vector transformPointLocal (Vector point);
+
+ /**
+ * Transforms a point by this matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector transformPoint (IVector point);
+
+ /**
+ * Transforms a point by this matrix and places the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector transformPoint (IVector point, Vector result);
+
+ /**
+ * Transforms a vector in-place by the inner 2x2 part of this matrix.
+ *
+ * @return a reference to the vector, for chaining.
+ */
+ Vector transformVectorLocal (Vector vector);
+
+ /**
+ * Transforms a vector by this inner 2x2 part of this matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector transformVector (IVector vector);
+
+ /**
+ * Transforms a vector by the inner 2x2 part of this matrix and places the result in the object
+ * provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector transformVector (IVector vector, Vector result);
+
+ /**
+ * Extracts the rotation component of the matrix. This uses the iterative polar decomposition
+ * algorithm described by
+ * Ken
+ * Shoemake.
+ */
+ double extractRotation ();
+
+ /**
+ * Extracts the scale component of the matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector extractScale ();
+
+ /**
+ * Extracts the scale component of the matrix and places it in the provided result vector.
+ *
+ * @return a reference to the result vector, for chaining.
+ */
+ Vector extractScale (Vector result);
+
+ /**
+ * Returns an approximation of the uniform scale for this matrix (the square root of the
+ * signed area of the parallelogram spanned by the axis vectors).
+ */
+ double approximateUniformScale ();
+}
diff --git a/src/main/java/pythagoras/d/IVector3.java b/src/main/java/pythagoras/d/IVector3.java
new file mode 100644
index 0000000..30cfab5
--- /dev/null
+++ b/src/main/java/pythagoras/d/IVector3.java
@@ -0,0 +1,221 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import java.nio.DoubleBuffer;
+
+/**
+ * Provides read-only access to a {@link Vector3}.
+ */
+public interface IVector3
+{
+ /** Returns the x-component of this vector. */
+ double x ();
+
+ /** Returns the y-component of this vector. */
+ double y ();
+
+ /** Returns the z-component of this vector. */
+ double z ();
+
+ /**
+ * Computes and returns the dot product of this and the specified other vector.
+ */
+ double dot (IVector3 other);
+
+ /**
+ * Computes the cross product of this and the specified other vector.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 cross (IVector3 other);
+
+ /**
+ * Computes the cross product of this and the specified other vector, placing the result
+ * in the object supplied.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 cross (IVector3 other, Vector3 result);
+
+ /**
+ * Computes the triple product of this and the specified other vectors, which is equal to
+ * this.dot(b.cross(c)).
+ */
+ double triple (IVector3 b, IVector3 c);
+
+ /**
+ * Negates this vector.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 negate ();
+
+ /**
+ * Negates this vector, storing the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 negate (Vector3 result);
+
+ /**
+ * Normalizes this vector.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 normalize ();
+
+ /**
+ * Normalizes this vector, storing the result in the object supplied.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 normalize (Vector3 result);
+
+ /**
+ * Returns the angle between this vector and the specified other vector.
+ */
+ double angle (IVector3 other);
+
+ /**
+ * Returns the length of this vector.
+ */
+ double length ();
+
+ /**
+ * Returns the squared length of this vector.
+ */
+ double lengthSquared ();
+
+ /**
+ * Returns the distance from this vector to the specified other vector.
+ */
+ double distance (IVector3 other);
+
+ /**
+ * Returns the squared distance from this vector to the specified other.
+ */
+ double distanceSquared (IVector3 other);
+
+ /**
+ * Returns the Manhattan distance between this vector and the specified other.
+ */
+ double manhattanDistance (IVector3 other);
+
+ /**
+ * Multiplies this vector by a scalar.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 mult (double v);
+
+ /**
+ * Multiplies this vector by a scalar and places the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 mult (double v, Vector3 result);
+
+ /**
+ * Multiplies this vector by another.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 mult (IVector3 other);
+
+ /**
+ * Multiplies this vector by another, storing the result in the object provided.
+ *
+ * @return a reference to the result vector, for chaining.
+ */
+ Vector3 mult (IVector3 other, Vector3 result);
+
+ /**
+ * Adds a vector to this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 add (IVector3 other);
+ /**
+ * Adds a vector to this one, storing the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ public IVector3 add (IVector3 other, Vector3 result);
+
+ /**
+ * Subtracts a vector from this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 subtract (IVector3 other);
+
+ /**
+ * Subtracts a vector from this one and places the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 subtract (IVector3 other, Vector3 result);
+
+ /**
+ * Adds a vector to this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 add (double x, double y, double z);
+
+ /**
+ * Adds a vector to this one and stores the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 add (double x, double y, double z, Vector3 result);
+
+ /**
+ * Adds a scaled vector to this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 addScaled (IVector3 other, double v);
+
+ /**
+ * Adds a scaled vector to this one and stores the result in the supplied vector.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 addScaled (IVector3 other, double v, Vector3 result);
+
+ /**
+ * Linearly interpolates between this and the specified other vector by the supplied amount.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 lerp (IVector3 other, double t);
+
+ /**
+ * Linearly interpolates between this and the supplied other vector by the supplied amount,
+ * storing the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 lerp (IVector3 other, double t, Vector3 result);
+
+ /**
+ * Returns the element at the idx'th position of the vector.
+ */
+ double get (int idx);
+
+ /**
+ * Populates the supplied array with the contents of this vector.
+ */
+ void get (double[] values);
+
+ /**
+ * Populates the supplied buffer with the contents of this vector.
+ *
+ * @return a reference to the buffer, for chaining.
+ */
+ DoubleBuffer get (DoubleBuffer buf);
+}
diff --git a/src/main/java/pythagoras/d/Matrix3.java b/src/main/java/pythagoras/d/Matrix3.java
new file mode 100644
index 0000000..a7f65fc
--- /dev/null
+++ b/src/main/java/pythagoras/d/Matrix3.java
@@ -0,0 +1,406 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import java.nio.DoubleBuffer;
+
+/**
+ * A 3x3 column-major matrix.
+ */
+public class Matrix3 extends AbstractMatrix3
+{
+ /** The identity matrix. */
+ public static final Matrix3 IDENTITY = new Matrix3();
+
+ /** The values of the matrix. */
+ public double m00, m10, m20;
+ public double m01, m11, m21;
+ public double m02, m12, m22;
+
+ /**
+ * Creates a matrix from its components.
+ */
+ public Matrix3 (double m00, double m10, double m20,
+ double m01, double m11, double m21,
+ double m02, double m12, double m22) {
+ set(m00, m10, m20,
+ m01, m11, m21,
+ m02, m12, m22);
+ }
+
+ /**
+ * Creates a matrix from an array of values.
+ */
+ public Matrix3 (double[] values) {
+ set(values);
+ }
+
+ /**
+ * Copy constructor.
+ */
+ public Matrix3 (Matrix3 other) {
+ set(other);
+ }
+
+ /**
+ * Creates an identity matrix.
+ */
+ public Matrix3 () {
+ setToIdentity();
+ }
+
+ /**
+ * Sets this matrix to the identity matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToIdentity () {
+ return set(
+ 1f, 0f, 0f,
+ 0f, 1f, 0f,
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets this to a rotation matrix that rotates one vector onto another.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (IVector3 from, IVector3 to) {
+ double angle = from.angle(to);
+ return (angle < 0.0001f) ?
+ setToIdentity() : setToRotation(angle, from.cross(to).normalizeLocal());
+ }
+
+ /**
+ * Sets this to a rotation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (double angle, IVector3 axis) {
+ return setToRotation(angle, axis.x(), axis.y(), axis.z());
+ }
+
+ /**
+ * Sets this to a rotation matrix. The formula comes from the OpenGL documentation for the
+ * glRotatef function.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (double angle, double x, double y, double z) {
+ double c = Math.cos(angle), s = Math.sin(angle), omc = 1f - c;
+ double xs = x*s, ys = y*s, zs = z*s, xy = x*y, xz = x*z, yz = y*z;
+ return set(
+ x*x*omc + c, xy*omc - zs, xz*omc + ys,
+ xy*omc + zs, y*y*omc + c, yz*omc - xs,
+ xz*omc - ys, yz*omc + xs, z*z*omc + c);
+ }
+
+ // /**
+ // * Sets this to a rotation matrix. The formula comes from the
+ // * Matrix and Quaternion FAQ.
+ // *
+ // * @return a reference to this matrix, for chaining.
+ // */
+ // public Matrix3 setToRotation (Quaternion quat) {
+ // double xx = quat.x*quat.x, yy = quat.y*quat.y, zz = quat.z*quat.z;
+ // double xy = quat.x*quat.y, xz = quat.x*quat.z, xw = quat.x*quat.w;
+ // double yz = quat.y*quat.z, yw = quat.y*quat.w, zw = quat.z*quat.w;
+ // return set(
+ // 1f - 2f*(yy + zz), 2f*(xy - zw), 2f*(xz + yw),
+ // 2f*(xy + zw), 1f - 2f*(xx + zz), 2f*(yz - xw),
+ // 2f*(xz - yw), 2f*(yz + xw), 1f - 2f*(xx + yy));
+ // }
+
+ /**
+ * Sets this to a scale matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToScale (IVector3 scale) {
+ return setToScale(scale.x(), scale.y(), scale.z());
+ }
+
+ /**
+ * Sets this to a uniform scale matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToScale (double s) {
+ return setToScale(s, s, s);
+ }
+
+ /**
+ * Sets this to a scale matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToScale (double x, double y, double z) {
+ return set(
+ x, 0f, 0f,
+ 0f, y, 0f,
+ 0f, 0f, z);
+ }
+
+ /**
+ * Sets this to a reflection across a plane intersecting the origin with the supplied normal.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToReflection (IVector3 normal) {
+ return setToReflection(normal.x(), normal.y(), normal.z());
+ }
+
+ /**
+ * Sets this to a reflection across a plane intersecting the origin with the supplied normal.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToReflection (double x, double y, double z) {
+ double x2 = -2f*x, y2 = -2f*y, z2 = -2f*z;
+ double xy2 = x2*y, xz2 = x2*z, yz2 = y2*z;
+ return set(
+ 1f + x2*x, xy2, xz2,
+ xy2, 1f + y2*y, yz2,
+ xz2, yz2, 1f + z2*z);
+ }
+
+ /**
+ * Sets this to a matrix that first rotates, then translates.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTransform (IVector translation, double rotation) {
+ return setToRotation(rotation).setTranslation(translation);
+ }
+
+ /**
+ * Sets this to a matrix that first scales, then rotates, then translates.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTransform (IVector translation, double rotation, double scale) {
+ return setToRotation(rotation).set(
+ m00 * scale, m10 * scale, translation.x(),
+ m01 * scale, m11 * scale, translation.y(),
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets this to a matrix that first scales, then rotates, then translates.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTransform (IVector translation, double rotation, IVector scale) {
+ double sx = scale.x(), sy = scale.y();
+ return setToRotation(rotation).set(
+ m00 * sx, m10 * sy, translation.x(),
+ m01 * sx, m11 * sy, translation.y(),
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets this to a translation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTranslation (IVector translation) {
+ return setToTranslation(translation.x(), translation.y());
+ }
+
+ /**
+ * Sets this to a translation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTranslation (double x, double y) {
+ return set(
+ 1f, 0f, x,
+ 0f, 1f, y,
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets the translation component of this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setTranslation (IVector translation) {
+ return setTranslation(translation.x(), translation.y());
+ }
+
+ /**
+ * Sets the translation component of this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setTranslation (double x, double y) {
+ m20 = x;
+ m21 = y;
+ return this;
+ }
+
+ /**
+ * Sets this to a rotation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (double angle) {
+ double sina = Math.sin(angle), cosa = Math.cos(angle);
+ return set(
+ cosa, -sina, 0f,
+ sina, cosa, 0f,
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Transposes this matrix in-place.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 transposeLocal () {
+ return transpose(this);
+ }
+
+ /**
+ * Multiplies this matrix in-place by another.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 multLocal (IMatrix3 other) {
+ return mult(other, this);
+ }
+
+ /**
+ * Multiplies this matrix in-place by another, treating the matricees as affine.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 multAffineLocal (IMatrix3 other) {
+ return multAffine(other, this);
+ }
+
+ /**
+ * Inverts this matrix in-place.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 invertLocal () {
+ return invert(this);
+ }
+
+ /**
+ * Inverts this matrix in-place as an affine matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 invertAffineLocal () {
+ return invertAffine(this);
+ }
+
+ /**
+ * Linearly interpolates between the this and the specified other matrix, placing the result in
+ * this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 lerpLocal (IMatrix3 other, double t) {
+ return lerp(other, t, this);
+ }
+
+ /**
+ * Linearly interpolates between this and the specified other matrix (treating the matrices as
+ * affine), placing the result in this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 lerpAffineLocal (IMatrix3 other, double t) {
+ return lerpAffine(other, t, this);
+ }
+
+ /**
+ * Copies the contents of another matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 set (IMatrix3 other) {
+ return set(
+ other.m00(), other.m10(), other.m20(),
+ other.m01(), other.m11(), other.m21(),
+ other.m02(), other.m12(), other.m22());
+ }
+
+ /**
+ * Copies the elements of an array.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 set (double[] values) {
+ return set(
+ values[0], values[1], values[2],
+ values[3], values[4], values[5],
+ values[6], values[7], values[8]);
+ }
+
+ /**
+ * Sets all of the matrix's components at once.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 set (
+ double m00, double m10, double m20,
+ double m01, double m11, double m21,
+ double m02, double m12, double m22) {
+ this.m00 = m00; this.m01 = m01; this.m02 = m02;
+ this.m10 = m10; this.m11 = m11; this.m12 = m12;
+ this.m20 = m20; this.m21 = m21; this.m22 = m22;
+ return this;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m00 () {
+ return m00;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m10 () {
+ return m10;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m20 () {
+ return m20;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m01 () {
+ return m01;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m11 () {
+ return m11;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m21 () {
+ return m21;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m02 () {
+ return m02;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m12 () {
+ return m12;
+ }
+
+ @Override // from AbstractMatrix3
+ public double m22 () {
+ return m22;
+ }
+}
diff --git a/src/main/java/pythagoras/d/Vector3.java b/src/main/java/pythagoras/d/Vector3.java
new file mode 100644
index 0000000..6b2b407
--- /dev/null
+++ b/src/main/java/pythagoras/d/Vector3.java
@@ -0,0 +1,206 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import java.io.Serializable;
+
+/**
+ * A three element vector.
+ */
+public class Vector3 extends AbstractVector3 implements Serializable
+{
+ /** A unit vector in the X+ direction. */
+ public static final IVector3 UNIT_X = new Vector3(1f, 0f, 0f);
+
+ /** A unit vector in the Y+ direction. */
+ public static final IVector3 UNIT_Y = new Vector3(0f, 1f, 0f);
+
+ /** A unit vector in the Z+ direction. */
+ public static final IVector3 UNIT_Z = new Vector3(0f, 0f, 1f);
+
+ /** A vector containing unity for all components. */
+ public static final IVector3 UNIT_XYZ = new Vector3(1f, 1f, 1f);
+
+ /** A normalized version of UNIT_XYZ. */
+ public static final IVector3 NORMAL_XYZ = UNIT_XYZ.normalize();
+
+ /** The zero vector. */
+ public static final IVector3 ZERO = new Vector3(0f, 0f, 0f);
+
+ /** A vector containing the minimum doubleing point value for all components
+ * (note: the components are -{@link Float#MAX_VALUE}, not {@link Float#MIN_VALUE}). */
+ public static final IVector3 MIN_VALUE =
+ new Vector3(-Float.MAX_VALUE, -Float.MAX_VALUE, -Float.MAX_VALUE);
+
+ /** A vector containing the maximum doubleing point value for all components. */
+ public static final IVector3 MAX_VALUE =
+ new Vector3(Float.MAX_VALUE, Float.MAX_VALUE, Float.MAX_VALUE);
+
+ /** The components of the vector. */
+ public double x, y, z;
+
+ /**
+ * Creates a vector from three components.
+ */
+ public Vector3 (double x, double y, double z) {
+ set(x, y, z);
+ }
+
+ /**
+ * Creates a vector from an array of values.
+ */
+ public Vector3 (double[] values) {
+ set(values);
+ }
+
+ /**
+ * Copy constructor.
+ */
+ public Vector3 (IVector3 other) {
+ set(other);
+ }
+
+ /**
+ * Creates a zero vector.
+ */
+ public Vector3 () {
+ }
+
+ /**
+ * Computes the cross product of this and the specified other vector, storing the result
+ * in this vector.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 crossLocal (IVector3 other) {
+ return cross(other, this);
+ }
+
+ /**
+ * Negates this vector in-place.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 negateLocal () {
+ return negate(this);
+ }
+
+ /**
+ * Normalizes this vector in-place.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 normalizeLocal () {
+ return normalize(this);
+ }
+
+ /**
+ * Multiplies this vector in-place by a scalar.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 multLocal (double v) {
+ return mult(v, this);
+ }
+
+ /**
+ * Multiplies this vector in-place by another.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 multLocal (IVector3 other) {
+ return mult(other, this);
+ }
+
+ /**
+ * Adds a vector in-place to this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 addLocal (IVector3 other) {
+ return add(other, this);
+ }
+
+ /**
+ * Subtracts a vector in-place from this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 subtractLocal (IVector3 other) {
+ return subtract(other, this);
+ }
+
+ /**
+ * Adds a vector in-place to this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 addLocal (double x, double y, double z) {
+ return add(x, y, z, this);
+ }
+
+ /**
+ * Adds a scaled vector in-place to this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 addScaledLocal (IVector3 other, double v) {
+ return addScaled(other, v, this);
+ }
+
+ /**
+ * Linearly interpolates between this and the specified other vector in-place by the supplied
+ * amount.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 lerpLocal (IVector3 other, double t) {
+ return lerp(other, t, this);
+ }
+ /**
+ * Copies the elements of another vector.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 set (IVector3 other) {
+ return set(other.x(), other.y(), other.z());
+ }
+
+ /**
+ * Copies the elements of an array.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 set (double[] values) {
+ return set(values[0], values[1], values[2]);
+ }
+
+ /**
+ * Sets all of the elements of the vector.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 set (double x, double y, double z) {
+ this.x = x;
+ this.y = y;
+ this.z = z;
+ return this;
+ }
+
+ @Override // from AbstractVector3
+ public double x () {
+ return x;
+ }
+
+ @Override // from AbstractVector3
+ public double y () {
+ return y;
+ }
+
+ @Override // from AbstractVector3
+ public double z () {
+ return z;
+ }
+}
diff --git a/src/main/java/pythagoras/f/AbstractMatrix3.java b/src/main/java/pythagoras/f/AbstractMatrix3.java
new file mode 100644
index 0000000..08e658e
--- /dev/null
+++ b/src/main/java/pythagoras/f/AbstractMatrix3.java
@@ -0,0 +1,346 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.f;
+
+import java.nio.FloatBuffer;
+
+import pythagoras.util.Platform;
+import pythagoras.util.SingularMatrixException;
+
+/**
+ * Provides most of the implementation of {@link IMatrix3}, obtaining only the components from the
+ * derived class.
+ */
+public abstract class AbstractMatrix3 implements IMatrix3
+{
+ @Override // from IVector3
+ public Matrix3 transpose () {
+ return transpose(new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 transpose (Matrix3 result) {
+ return result.set(
+ m00(), m01(), m02(),
+ m10(), m11(), m12(),
+ m20(), m21(), m22());
+ }
+
+ @Override // from IVector3
+ public Matrix3 mult (IMatrix3 other) {
+ return mult(other, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 mult (IMatrix3 other, Matrix3 result) {
+ float m00 = m00(), m01 = m01(), m02 = m02();
+ float m10 = m10(), m11 = m11(), m12 = m12();
+ float m20 = m20(), m21 = m21(), m22 = m22();
+ float om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ float om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ float om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00*om00 + m10*om01 + m20*om02,
+ m00*om10 + m10*om11 + m20*om12,
+ m00*om20 + m10*om21 + m20*om22,
+
+ m01*om00 + m11*om01 + m21*om02,
+ m01*om10 + m11*om11 + m21*om12,
+ m01*om20 + m11*om21 + m21*om22,
+
+ m02*om00 + m12*om01 + m22*om02,
+ m02*om10 + m12*om11 + m22*om12,
+ m02*om20 + m12*om21 + m22*om22);
+ }
+
+ @Override // from IVector3
+ public boolean isAffine () {
+ return (m02() == 0f && m12() == 0f && m22() == 1f);
+ }
+
+ @Override // from IVector3
+ public Matrix3 multAffine (IMatrix3 other) {
+ return multAffine(other, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 multAffine (IMatrix3 other, Matrix3 result) {
+ float m00 = m00(), m01 = m01(), m02 = m02();
+ float m10 = m10(), m11 = m11(), m12 = m12();
+ float m20 = m20(), m21 = m21(), m22 = m22();
+ float om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ float om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ float om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00*om00 + m10*om01,
+ m00*om10 + m10*om11,
+ m00*om20 + m10*om21 + m20,
+
+ m01*om00 + m11*om01,
+ m01*om10 + m11*om11,
+ m01*om20 + m11*om21 + m21,
+
+ 0f, 0f, 1f);
+ }
+
+ @Override // from IVector3
+ public Matrix3 invert () {
+ return invert(new Matrix3());
+ }
+
+ /**
+ * Inverts this matrix and places the result in the given object. This code is based on the
+ * examples in the Matrix and
+ * Quaternion FAQ.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ public Matrix3 invert (Matrix3 result) throws SingularMatrixException {
+ float m00 = m00(), m01 = m01(), m02 = m02();
+ float m10 = m10(), m11 = m11(), m12 = m12();
+ float m20 = m20(), m21 = m21(), m22 = m22();
+ // compute the determinant, storing the subdeterminants for later use
+ float sd00 = m11*m22 - m21*m12;
+ float sd10 = m01*m22 - m21*m02;
+ float sd20 = m01*m12 - m11*m02;
+ float det = m00*sd00 + m20*sd20 - m10*sd10;
+ if (Math.abs(det) == 0f) {
+ // determinant is zero; matrix is not invertible
+ throw new SingularMatrixException(this.toString());
+ }
+ float rdet = 1f / det;
+ return result.set(
+ +sd00 * rdet,
+ -(m10*m22 - m20*m12) * rdet,
+ +(m10*m21 - m20*m11) * rdet,
+
+ -sd10 * rdet,
+ +(m00*m22 - m20*m02) * rdet,
+ -(m00*m21 - m20*m01) * rdet,
+
+ +sd20 * rdet,
+ -(m00*m12 - m10*m02) * rdet,
+ +(m00*m11 - m10*m01) * rdet);
+ }
+
+ @Override // from IVector3
+ public Matrix3 invertAffine () {
+ return invertAffine(new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 invertAffine (Matrix3 result) throws SingularMatrixException {
+ float m00 = m00(), m01 = m01(), m02 = m02();
+ float m10 = m10(), m11 = m11(), m12 = m12();
+ float m20 = m20(), m21 = m21(), m22 = m22();
+ // compute the determinant, storing the subdeterminants for later use
+ float det = m00*m11 - m10*m01;
+ if (Math.abs(det) == 0f) {
+ // determinant is zero; matrix is not invertible
+ throw new SingularMatrixException(this.toString());
+ }
+ float rdet = 1f / det;
+ return result.set(
+ +m11 * rdet,
+ -m10 * rdet,
+ +(m10*m21 - m20*m11) * rdet,
+
+ -m01 * rdet,
+ +m00 * rdet,
+ -(m00*m21 - m20*m01) * rdet,
+
+ 0f, 0f, 1f);
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerp (IMatrix3 other, float t) {
+ return lerp(other, t, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerp (IMatrix3 other, float t, Matrix3 result) {
+ float m00 = m00(), m01 = m01(), m02 = m02();
+ float m10 = m10(), m11 = m11(), m12 = m12();
+ float m20 = m20(), m21 = m21(), m22 = m22();
+ float om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ float om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ float om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00 + t*(om00 - m00),
+ m10 + t*(om10 - m10),
+ m20 + t*(om20 - m20),
+
+ m01 + t*(om01 - m01),
+ m11 + t*(om11 - m11),
+ m21 + t*(om21 - m21),
+
+ m02 + t*(om02 - m02),
+ m12 + t*(om12 - m12),
+ m22 + t*(om22 - m22));
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerpAffine (IMatrix3 other, float t) {
+ return lerpAffine(other, t, new Matrix3());
+ }
+
+ @Override // from IVector3
+ public Matrix3 lerpAffine (IMatrix3 other, float t, Matrix3 result) {
+ float m00 = m00(), m01 = m01(), m02 = m02();
+ float m10 = m10(), m11 = m11(), m12 = m12();
+ float m20 = m20(), m21 = m21(), m22 = m22();
+ float om00 = other.m00(), om01 = other.m01(), om02 = other.m02();
+ float om10 = other.m10(), om11 = other.m11(), om12 = other.m12();
+ float om20 = other.m20(), om21 = other.m21(), om22 = other.m22();
+ return result.set(
+ m00 + t*(om00 - m00),
+ m10 + t*(om10 - m10),
+ m20 + t*(om20 - m20),
+
+ m01 + t*(om01 - m01),
+ m11 + t*(om11 - m11),
+ m21 + t*(om21 - m21),
+
+ 0f, 0f, 1f);
+ }
+
+ @Override // from IVector3
+ public FloatBuffer get (FloatBuffer buf) {
+ buf.put(m00()).put(m01()).put(m02());
+ buf.put(m10()).put(m11()).put(m12());
+ buf.put(m20()).put(m21()).put(m22());
+ return buf;
+ }
+
+ @Override // from IVector3
+ public Vector3 transformLocal (Vector3 vector) {
+ return transform(vector, vector);
+ }
+
+ @Override // from IVector3
+ public Vector3 transform (IVector3 vector) {
+ return transform(vector, new Vector3());
+ }
+
+ @Override // from IVector3
+ public Vector3 transform (IVector3 vector, Vector3 result) {
+ float vx = vector.x(), vy = vector.y(), vz = vector.z();
+ return result.set(
+ m00()*vx + m10()*vy + m20()*vz,
+ m01()*vx + m11()*vy + m21()*vz,
+ m02()*vx + m12()*vy + m22()*vz);
+ }
+
+ @Override // from IVector3
+ public Vector transformPointLocal (Vector point) {
+ return transformPoint(point, point);
+ }
+
+ @Override // from IVector3
+ public Vector transformPoint (IVector point) {
+ return transformPoint(point, new Vector());
+ }
+
+ @Override // from IVector3
+ public Vector transformPoint (IVector point, Vector result) {
+ float px = point.x(), py = point.y();
+ return result.set(m00()*px + m10()*py + m20(), m01()*px + m11()*py + m21());
+ }
+
+ @Override // from IVector3
+ public Vector transformVectorLocal (Vector vector) {
+ return transformVector(vector, vector);
+ }
+
+ @Override // from IVector3
+ public Vector transformVector (IVector vector) {
+ return transformVector(vector, new Vector());
+ }
+
+ @Override // from IVector3
+ public Vector transformVector (IVector vector, Vector result) {
+ float vx = vector.x(), vy = vector.y();
+ return result.set(m00()*vx + m10()*vy, m01()*vx + m11()*vy);
+ }
+
+ @Override // from IVector3
+ public float extractRotation () {
+ // start with the contents of the upper 2x2 portion of the matrix
+ float n00 = m00(), n10 = m10();
+ float n01 = m01(), n11 = m11();
+ for (int ii = 0; ii < 10; ii++) {
+ // store the results of the previous iteration
+ float o00 = n00, o10 = n10;
+ float o01 = n01, o11 = n11;
+
+ // compute average of the matrix with its inverse transpose
+ float det = o00*o11 - o10*o01;
+ if (Math.abs(det) == 0f) {
+ // determinant is zero; matrix is not invertible
+ throw new SingularMatrixException(this.toString());
+ }
+ float hrdet = 0.5f / det;
+ n00 = +o11 * hrdet + o00*0.5f;
+ n10 = -o01 * hrdet + o10*0.5f;
+
+ n01 = -o10 * hrdet + o01*0.5f;
+ n11 = +o00 * hrdet + o11*0.5f;
+
+ // compute the difference; if it's small enough, we're done
+ float d00 = n00 - o00, d10 = n10 - o10;
+ float d01 = n01 - o01, d11 = n11 - o11;
+ if (d00*d00 + d10*d10 + d01*d01 + d11*d11 < MathUtil.EPSILON) {
+ break;
+ }
+ }
+ // now that we have a nice orthogonal matrix, we can extract the rotation
+ return FloatMath.atan2(n01, n00);
+ }
+
+ @Override // from IVector3
+ public Vector extractScale () {
+ return extractScale(new Vector());
+ }
+
+ @Override // from IVector3
+ public Vector extractScale (Vector result) {
+ float m00 = m00(), m01 = m01(), m10 = m10(), m11 = m11();
+ return result.set(
+ FloatMath.sqrt(m00*m00 + m01*m01),
+ FloatMath.sqrt(m10*m10 + m11*m11));
+ }
+
+ @Override // from IVector3
+ public float approximateUniformScale () {
+ float cp = m00()*m11() - m01()*m10();
+ return (cp < 0f) ? -FloatMath.sqrt(-cp) : FloatMath.sqrt(cp);
+ }
+
+ @Override
+ public String toString () {
+ return "[[" + m00() + ", " + m10() + ", " + m20() + "], " +
+ "[" + m01() + ", " + m11() + ", " + m21() + "], " +
+ "[" + m02() + ", " + m12() + ", " + m22() + "]]";
+ }
+
+ @Override
+ public int hashCode () {
+ return Platform.hashCode(m00()) ^ Platform.hashCode(m10()) ^ Platform.hashCode(m20()) ^
+ Platform.hashCode(m01()) ^ Platform.hashCode(m11()) ^ Platform.hashCode(m21()) ^
+ Platform.hashCode(m02()) ^ Platform.hashCode(m12()) ^ Platform.hashCode(m22());
+ }
+
+ @Override
+ public boolean equals (Object other) {
+ if (!(other instanceof AbstractMatrix3)) {
+ return false;
+ }
+ AbstractMatrix3 omat = (AbstractMatrix3)other;
+ return
+ m00() == omat.m00() && m10() == omat.m10() && m20() == omat.m20() &&
+ m01() == omat.m01() && m11() == omat.m11() && m21() == omat.m21() &&
+ m02() == omat.m02() && m12() == omat.m12() && m22() == omat.m22();
+ }
+}
diff --git a/src/main/java/pythagoras/f/AbstractVector3.java b/src/main/java/pythagoras/f/AbstractVector3.java
new file mode 100644
index 0000000..895601e
--- /dev/null
+++ b/src/main/java/pythagoras/f/AbstractVector3.java
@@ -0,0 +1,204 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.f;
+
+import java.nio.FloatBuffer;
+
+import pythagoras.util.Platform;
+
+/**
+ * Provides most of the implementation of {@link IVector3}, obtaining only x, y and z from the
+ * derived class.
+ */
+public abstract class AbstractVector3 implements IVector3
+{
+ @Override // from interface IVector3
+ public float dot (IVector3 other) {
+ return x()*other.x() + y()*other.y() + z()*other.z();
+ }
+
+ @Override // from interface IVector3
+ public Vector3 cross (IVector3 other) {
+ return cross(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 cross (IVector3 other, Vector3 result) {
+ float x = x(), y = y(), z = z();
+ float ox = other.x(), oy = other.y(), oz = other.z();
+ return result.set(y*oz - z*oy, z*ox - x*oz, x*oy - y*ox);
+ }
+
+ @Override // from interface IVector3
+ public float triple (IVector3 b, IVector3 c) {
+ float bx = b.x(), by = b.y(), bz = b.z();
+ float cx = c.x(), cy = c.y(), cz = c.z();
+ return x()*(by*cz - bz*cy) + y()*(bz*cx - bx*cz) + z()*(bx*cy - by*cx);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 negate () {
+ return negate(new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 negate (Vector3 result) {
+ return result.set(-x(), -y(), -z());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 normalize () {
+ return normalize(new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 normalize (Vector3 result) {
+ return mult(1f / length(), result);
+ }
+
+ @Override // from interface IVector3
+ public float angle (IVector3 other) {
+ return FloatMath.acos(dot(other) / (length() * other.length()));
+ }
+
+ @Override // from interface IVector3
+ public float length () {
+ return FloatMath.sqrt(lengthSquared());
+ }
+
+ @Override // from interface IVector3
+ public float lengthSquared () {
+ float x = x(), y = y(), z = z();
+ return (x*x + y*y + z*z);
+ }
+
+ @Override // from interface IVector3
+ public float distance (IVector3 other) {
+ return FloatMath.sqrt(distanceSquared(other));
+ }
+
+ @Override // from interface IVector3
+ public float distanceSquared (IVector3 other) {
+ float dx = x() - other.x(), dy = y() - other.y(), dz = z() - other.z();
+ return dx*dx + dy*dy + dz*dz;
+ }
+
+ @Override // from interface IVector3
+ public float manhattanDistance (IVector3 other) {
+ return Math.abs(x() - other.x()) + Math.abs(y() - other.y()) + Math.abs(z() - other.z());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (float v) {
+ return mult(v, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (float v, Vector3 result) {
+ return result.set(x()*v, y()*v, z()*v);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (IVector3 other) {
+ return mult(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 mult (IVector3 other, Vector3 result) {
+ return result.set(x()*other.x(), y()*other.y(), z()*other.z());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (IVector3 other) {
+ return add(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (IVector3 other, Vector3 result) {
+ return add(other.x(), other.y(), other.z(), result);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 subtract (IVector3 other) {
+ return subtract(other, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 subtract (IVector3 other, Vector3 result) {
+ return add(-other.x(), -other.y(), -other.z(), result);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (float x, float y, float z) {
+ return add(x, y, z, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 add (float x, float y, float z, Vector3 result) {
+ return result.set(x() + x, y() + y, z() + z);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 addScaled (IVector3 other, float v) {
+ return addScaled(other, v, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 addScaled (IVector3 other, float v, Vector3 result) {
+ return result.set(x() + other.x()*v, y() + other.y()*v, z() + other.z()*v);
+ }
+
+ @Override // from interface IVector3
+ public Vector3 lerp (IVector3 other, float t) {
+ return lerp(other, t, new Vector3());
+ }
+
+ @Override // from interface IVector3
+ public Vector3 lerp (IVector3 other, float t, Vector3 result) {
+ float x = x(), y = y(), z = z();
+ return result.set(x + t*(other.x() - x), y + t*(other.y() - y), z + t*(other.z() - z));
+ }
+
+ @Override // from interface IVector3
+ public float get (int idx) {
+ switch (idx) {
+ case 0: return x();
+ case 1: return y();
+ case 2: return z();
+ }
+ throw new IndexOutOfBoundsException(String.valueOf(idx));
+ }
+
+ @Override // from interface IVector3
+ public void get (float[] values) {
+ values[0] = x();
+ values[1] = y();
+ values[2] = z();
+ }
+
+ @Override // from interface IVector3
+ public FloatBuffer get (FloatBuffer buf) {
+ return buf.put(x()).put(y()).put(z());
+ }
+
+ @Override
+ public String toString () {
+ return "[" + x() + ", " + y() + ", " + z() + "]";
+ }
+
+ @Override
+ public int hashCode () {
+ return Platform.hashCode(x()) ^ Platform.hashCode(y()) ^ Platform.hashCode(z());
+ }
+
+ @Override
+ public boolean equals (Object other) {
+ if (!(other instanceof AbstractVector3)) {
+ return false;
+ }
+ AbstractVector3 ovec = (AbstractVector3)other;
+ return (x() == ovec.x() && y() == ovec.y() && z() == ovec.z());
+ }
+}
diff --git a/src/main/java/pythagoras/f/IMatrix3.java b/src/main/java/pythagoras/f/IMatrix3.java
new file mode 100644
index 0000000..2ce605d
--- /dev/null
+++ b/src/main/java/pythagoras/f/IMatrix3.java
@@ -0,0 +1,250 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.f;
+
+import java.nio.FloatBuffer;
+
+import pythagoras.util.SingularMatrixException;
+
+/**
+ * Provides read-only access to a {@link Matrix3}.
+ */
+interface IMatrix3
+{
+ /** Returns the (0,0)th component of the matrix. */
+ float m00 ();
+
+ /** Returns the (1,0)th component of the matrix. */
+ float m10 ();
+
+ /** Returns the (2,0)th component of the matrix. */
+ float m20 ();
+
+ /** Returns the (0,1)th component of the matrix. */
+ float m01 ();
+
+ /** Returns the (1,1)th component of the matrix. */
+ float m11 ();
+
+ /** Returns the (2,1)th component of the matrix. */
+ float m21 ();
+
+ /** Returns the (0,2)th component of the matrix. */
+ float m02 ();
+
+ /** Returns the (1,2)th component of the matrix. */
+ float m12 ();
+
+ /** Returns the (2,2)th component of the matrix. */
+ float m22 ();
+
+ /**
+ * Transposes this matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 transpose ();
+
+ /**
+ * Transposes this matrix, storing the result in the provided object.
+ *
+ * @return the result matrix, for chaining.
+ */
+ Matrix3 transpose (Matrix3 result);
+
+ /**
+ * Multiplies this matrix by another.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 mult (IMatrix3 other);
+
+ /**
+ * Multiplies this matrix by another and stores the result in the object provided.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 mult (IMatrix3 other, Matrix3 result);
+
+ /**
+ * Determines whether this matrix represents an affine transformation.
+ */
+ boolean isAffine ();
+
+ /**
+ * Multiplies this matrix by another, treating the matrices as affine.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 multAffine (IMatrix3 other);
+
+ /**
+ * Multiplies this matrix by another, treating the matrices as affine, and stores the result
+ * in the object provided.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 multAffine (IMatrix3 other, Matrix3 result);
+
+ /**
+ * Inverts this matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 invert ();
+
+ /**
+ * Inverts this matrix and places the result in the given object. This code is based on the
+ * examples in the Matrix and
+ * Quaternion FAQ.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 invert (Matrix3 result) throws SingularMatrixException;
+
+ /**
+ * Inverts this matrix as an affine matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 invertAffine ();
+
+ /**
+ * Inverts this matrix as an affine matrix and places the result in the given object.
+ *
+ * @return a reference to the result matrix, for chaining.
+ */
+ Matrix3 invertAffine (Matrix3 result) throws SingularMatrixException;
+
+ /**
+ * Linearly interpolates between this and the specified other matrix.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 lerp (IMatrix3 other, float t);
+
+ /**
+ * Linearly interpolates between this and the specified other matrix, placing the result in
+ * the object provided.
+ *
+ * @return a reference to the result object, for chaining.
+ */
+ Matrix3 lerp (IMatrix3 other, float t, Matrix3 result);
+
+ /**
+ * Linearly interpolates between this and the specified other matrix, treating the matrices as
+ * affine.
+ *
+ * @return a new matrix containing the result.
+ */
+ Matrix3 lerpAffine (IMatrix3 other, float t);
+
+ /**
+ * Linearly interpolates between this and the specified other matrix (treating the matrices as
+ * affine), placing the result in the object provided.
+ *
+ * @return a reference to the result object, for chaining.
+ */
+ Matrix3 lerpAffine (IMatrix3 other, float t, Matrix3 result);
+
+ /**
+ * Places the contents of this matrix into the given buffer in the standard OpenGL order.
+ *
+ * @return a reference to the buffer, for chaining.
+ */
+ FloatBuffer get (FloatBuffer buf);
+
+ /**
+ * Transforms a vector in-place by the inner 3x3 part of this matrix.
+ *
+ * @return a reference to the vector, for chaining.
+ */
+ Vector3 transformLocal (Vector3 vector);
+
+ /**
+ * Transforms a vector by this matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 transform (IVector3 vector);
+
+ /**
+ * Transforms a vector by this matrix and places the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 transform (IVector3 vector, Vector3 result);
+
+ /**
+ * Transforms a point in-place by this matrix.
+ *
+ * @return a reference to the point, for chaining.
+ */
+ Vector transformPointLocal (Vector point);
+
+ /**
+ * Transforms a point by this matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector transformPoint (IVector point);
+
+ /**
+ * Transforms a point by this matrix and places the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector transformPoint (IVector point, Vector result);
+
+ /**
+ * Transforms a vector in-place by the inner 2x2 part of this matrix.
+ *
+ * @return a reference to the vector, for chaining.
+ */
+ Vector transformVectorLocal (Vector vector);
+
+ /**
+ * Transforms a vector by this inner 2x2 part of this matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector transformVector (IVector vector);
+
+ /**
+ * Transforms a vector by the inner 2x2 part of this matrix and places the result in the object
+ * provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector transformVector (IVector vector, Vector result);
+
+ /**
+ * Extracts the rotation component of the matrix. This uses the iterative polar decomposition
+ * algorithm described by
+ * Ken
+ * Shoemake.
+ */
+ float extractRotation ();
+
+ /**
+ * Extracts the scale component of the matrix.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector extractScale ();
+
+ /**
+ * Extracts the scale component of the matrix and places it in the provided result vector.
+ *
+ * @return a reference to the result vector, for chaining.
+ */
+ Vector extractScale (Vector result);
+
+ /**
+ * Returns an approximation of the uniform scale for this matrix (the square root of the
+ * signed area of the parallelogram spanned by the axis vectors).
+ */
+ float approximateUniformScale ();
+}
diff --git a/src/main/java/pythagoras/f/IVector3.java b/src/main/java/pythagoras/f/IVector3.java
new file mode 100644
index 0000000..7fa2270
--- /dev/null
+++ b/src/main/java/pythagoras/f/IVector3.java
@@ -0,0 +1,221 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.f;
+
+import java.nio.FloatBuffer;
+
+/**
+ * Provides read-only access to a {@link Vector3}.
+ */
+public interface IVector3
+{
+ /** Returns the x-component of this vector. */
+ float x ();
+
+ /** Returns the y-component of this vector. */
+ float y ();
+
+ /** Returns the z-component of this vector. */
+ float z ();
+
+ /**
+ * Computes and returns the dot product of this and the specified other vector.
+ */
+ float dot (IVector3 other);
+
+ /**
+ * Computes the cross product of this and the specified other vector.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 cross (IVector3 other);
+
+ /**
+ * Computes the cross product of this and the specified other vector, placing the result
+ * in the object supplied.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 cross (IVector3 other, Vector3 result);
+
+ /**
+ * Computes the triple product of this and the specified other vectors, which is equal to
+ * this.dot(b.cross(c)).
+ */
+ float triple (IVector3 b, IVector3 c);
+
+ /**
+ * Negates this vector.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 negate ();
+
+ /**
+ * Negates this vector, storing the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 negate (Vector3 result);
+
+ /**
+ * Normalizes this vector.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 normalize ();
+
+ /**
+ * Normalizes this vector, storing the result in the object supplied.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 normalize (Vector3 result);
+
+ /**
+ * Returns the angle between this vector and the specified other vector.
+ */
+ float angle (IVector3 other);
+
+ /**
+ * Returns the length of this vector.
+ */
+ float length ();
+
+ /**
+ * Returns the squared length of this vector.
+ */
+ float lengthSquared ();
+
+ /**
+ * Returns the distance from this vector to the specified other vector.
+ */
+ float distance (IVector3 other);
+
+ /**
+ * Returns the squared distance from this vector to the specified other.
+ */
+ float distanceSquared (IVector3 other);
+
+ /**
+ * Returns the Manhattan distance between this vector and the specified other.
+ */
+ float manhattanDistance (IVector3 other);
+
+ /**
+ * Multiplies this vector by a scalar.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 mult (float v);
+
+ /**
+ * Multiplies this vector by a scalar and places the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 mult (float v, Vector3 result);
+
+ /**
+ * Multiplies this vector by another.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 mult (IVector3 other);
+
+ /**
+ * Multiplies this vector by another, storing the result in the object provided.
+ *
+ * @return a reference to the result vector, for chaining.
+ */
+ Vector3 mult (IVector3 other, Vector3 result);
+
+ /**
+ * Adds a vector to this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 add (IVector3 other);
+ /**
+ * Adds a vector to this one, storing the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ public IVector3 add (IVector3 other, Vector3 result);
+
+ /**
+ * Subtracts a vector from this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 subtract (IVector3 other);
+
+ /**
+ * Subtracts a vector from this one and places the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 subtract (IVector3 other, Vector3 result);
+
+ /**
+ * Adds a vector to this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 add (float x, float y, float z);
+
+ /**
+ * Adds a vector to this one and stores the result in the object provided.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 add (float x, float y, float z, Vector3 result);
+
+ /**
+ * Adds a scaled vector to this one.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 addScaled (IVector3 other, float v);
+
+ /**
+ * Adds a scaled vector to this one and stores the result in the supplied vector.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 addScaled (IVector3 other, float v, Vector3 result);
+
+ /**
+ * Linearly interpolates between this and the specified other vector by the supplied amount.
+ *
+ * @return a new vector containing the result.
+ */
+ Vector3 lerp (IVector3 other, float t);
+
+ /**
+ * Linearly interpolates between this and the supplied other vector by the supplied amount,
+ * storing the result in the supplied object.
+ *
+ * @return a reference to the result, for chaining.
+ */
+ Vector3 lerp (IVector3 other, float t, Vector3 result);
+
+ /**
+ * Returns the element at the idx'th position of the vector.
+ */
+ float get (int idx);
+
+ /**
+ * Populates the supplied array with the contents of this vector.
+ */
+ void get (float[] values);
+
+ /**
+ * Populates the supplied buffer with the contents of this vector.
+ *
+ * @return a reference to the buffer, for chaining.
+ */
+ FloatBuffer get (FloatBuffer buf);
+}
diff --git a/src/main/java/pythagoras/f/Matrix3.java b/src/main/java/pythagoras/f/Matrix3.java
new file mode 100644
index 0000000..ae0cfef
--- /dev/null
+++ b/src/main/java/pythagoras/f/Matrix3.java
@@ -0,0 +1,406 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.f;
+
+import java.nio.FloatBuffer;
+
+/**
+ * A 3x3 column-major matrix.
+ */
+public class Matrix3 extends AbstractMatrix3
+{
+ /** The identity matrix. */
+ public static final Matrix3 IDENTITY = new Matrix3();
+
+ /** The values of the matrix. */
+ public float m00, m10, m20;
+ public float m01, m11, m21;
+ public float m02, m12, m22;
+
+ /**
+ * Creates a matrix from its components.
+ */
+ public Matrix3 (float m00, float m10, float m20,
+ float m01, float m11, float m21,
+ float m02, float m12, float m22) {
+ set(m00, m10, m20,
+ m01, m11, m21,
+ m02, m12, m22);
+ }
+
+ /**
+ * Creates a matrix from an array of values.
+ */
+ public Matrix3 (float[] values) {
+ set(values);
+ }
+
+ /**
+ * Copy constructor.
+ */
+ public Matrix3 (Matrix3 other) {
+ set(other);
+ }
+
+ /**
+ * Creates an identity matrix.
+ */
+ public Matrix3 () {
+ setToIdentity();
+ }
+
+ /**
+ * Sets this matrix to the identity matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToIdentity () {
+ return set(
+ 1f, 0f, 0f,
+ 0f, 1f, 0f,
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets this to a rotation matrix that rotates one vector onto another.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (IVector3 from, IVector3 to) {
+ float angle = from.angle(to);
+ return (angle < 0.0001f) ?
+ setToIdentity() : setToRotation(angle, from.cross(to).normalizeLocal());
+ }
+
+ /**
+ * Sets this to a rotation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (float angle, IVector3 axis) {
+ return setToRotation(angle, axis.x(), axis.y(), axis.z());
+ }
+
+ /**
+ * Sets this to a rotation matrix. The formula comes from the OpenGL documentation for the
+ * glRotatef function.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (float angle, float x, float y, float z) {
+ float c = FloatMath.cos(angle), s = FloatMath.sin(angle), omc = 1f - c;
+ float xs = x*s, ys = y*s, zs = z*s, xy = x*y, xz = x*z, yz = y*z;
+ return set(
+ x*x*omc + c, xy*omc - zs, xz*omc + ys,
+ xy*omc + zs, y*y*omc + c, yz*omc - xs,
+ xz*omc - ys, yz*omc + xs, z*z*omc + c);
+ }
+
+ // /**
+ // * Sets this to a rotation matrix. The formula comes from the
+ // * Matrix and Quaternion FAQ.
+ // *
+ // * @return a reference to this matrix, for chaining.
+ // */
+ // public Matrix3 setToRotation (Quaternion quat) {
+ // float xx = quat.x*quat.x, yy = quat.y*quat.y, zz = quat.z*quat.z;
+ // float xy = quat.x*quat.y, xz = quat.x*quat.z, xw = quat.x*quat.w;
+ // float yz = quat.y*quat.z, yw = quat.y*quat.w, zw = quat.z*quat.w;
+ // return set(
+ // 1f - 2f*(yy + zz), 2f*(xy - zw), 2f*(xz + yw),
+ // 2f*(xy + zw), 1f - 2f*(xx + zz), 2f*(yz - xw),
+ // 2f*(xz - yw), 2f*(yz + xw), 1f - 2f*(xx + yy));
+ // }
+
+ /**
+ * Sets this to a scale matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToScale (IVector3 scale) {
+ return setToScale(scale.x(), scale.y(), scale.z());
+ }
+
+ /**
+ * Sets this to a uniform scale matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToScale (float s) {
+ return setToScale(s, s, s);
+ }
+
+ /**
+ * Sets this to a scale matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToScale (float x, float y, float z) {
+ return set(
+ x, 0f, 0f,
+ 0f, y, 0f,
+ 0f, 0f, z);
+ }
+
+ /**
+ * Sets this to a reflection across a plane intersecting the origin with the supplied normal.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToReflection (IVector3 normal) {
+ return setToReflection(normal.x(), normal.y(), normal.z());
+ }
+
+ /**
+ * Sets this to a reflection across a plane intersecting the origin with the supplied normal.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToReflection (float x, float y, float z) {
+ float x2 = -2f*x, y2 = -2f*y, z2 = -2f*z;
+ float xy2 = x2*y, xz2 = x2*z, yz2 = y2*z;
+ return set(
+ 1f + x2*x, xy2, xz2,
+ xy2, 1f + y2*y, yz2,
+ xz2, yz2, 1f + z2*z);
+ }
+
+ /**
+ * Sets this to a matrix that first rotates, then translates.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTransform (IVector translation, float rotation) {
+ return setToRotation(rotation).setTranslation(translation);
+ }
+
+ /**
+ * Sets this to a matrix that first scales, then rotates, then translates.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTransform (IVector translation, float rotation, float scale) {
+ return setToRotation(rotation).set(
+ m00 * scale, m10 * scale, translation.x(),
+ m01 * scale, m11 * scale, translation.y(),
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets this to a matrix that first scales, then rotates, then translates.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTransform (IVector translation, float rotation, IVector scale) {
+ float sx = scale.x(), sy = scale.y();
+ return setToRotation(rotation).set(
+ m00 * sx, m10 * sy, translation.x(),
+ m01 * sx, m11 * sy, translation.y(),
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets this to a translation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTranslation (IVector translation) {
+ return setToTranslation(translation.x(), translation.y());
+ }
+
+ /**
+ * Sets this to a translation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToTranslation (float x, float y) {
+ return set(
+ 1f, 0f, x,
+ 0f, 1f, y,
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Sets the translation component of this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setTranslation (IVector translation) {
+ return setTranslation(translation.x(), translation.y());
+ }
+
+ /**
+ * Sets the translation component of this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setTranslation (float x, float y) {
+ m20 = x;
+ m21 = y;
+ return this;
+ }
+
+ /**
+ * Sets this to a rotation matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 setToRotation (float angle) {
+ float sina = FloatMath.sin(angle), cosa = FloatMath.cos(angle);
+ return set(
+ cosa, -sina, 0f,
+ sina, cosa, 0f,
+ 0f, 0f, 1f);
+ }
+
+ /**
+ * Transposes this matrix in-place.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 transposeLocal () {
+ return transpose(this);
+ }
+
+ /**
+ * Multiplies this matrix in-place by another.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 multLocal (IMatrix3 other) {
+ return mult(other, this);
+ }
+
+ /**
+ * Multiplies this matrix in-place by another, treating the matricees as affine.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 multAffineLocal (IMatrix3 other) {
+ return multAffine(other, this);
+ }
+
+ /**
+ * Inverts this matrix in-place.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 invertLocal () {
+ return invert(this);
+ }
+
+ /**
+ * Inverts this matrix in-place as an affine matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 invertAffineLocal () {
+ return invertAffine(this);
+ }
+
+ /**
+ * Linearly interpolates between the this and the specified other matrix, placing the result in
+ * this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 lerpLocal (IMatrix3 other, float t) {
+ return lerp(other, t, this);
+ }
+
+ /**
+ * Linearly interpolates between this and the specified other matrix (treating the matrices as
+ * affine), placing the result in this matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 lerpAffineLocal (IMatrix3 other, float t) {
+ return lerpAffine(other, t, this);
+ }
+
+ /**
+ * Copies the contents of another matrix.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 set (IMatrix3 other) {
+ return set(
+ other.m00(), other.m10(), other.m20(),
+ other.m01(), other.m11(), other.m21(),
+ other.m02(), other.m12(), other.m22());
+ }
+
+ /**
+ * Copies the elements of an array.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 set (float[] values) {
+ return set(
+ values[0], values[1], values[2],
+ values[3], values[4], values[5],
+ values[6], values[7], values[8]);
+ }
+
+ /**
+ * Sets all of the matrix's components at once.
+ *
+ * @return a reference to this matrix, for chaining.
+ */
+ public Matrix3 set (
+ float m00, float m10, float m20,
+ float m01, float m11, float m21,
+ float m02, float m12, float m22) {
+ this.m00 = m00; this.m01 = m01; this.m02 = m02;
+ this.m10 = m10; this.m11 = m11; this.m12 = m12;
+ this.m20 = m20; this.m21 = m21; this.m22 = m22;
+ return this;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m00 () {
+ return m00;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m10 () {
+ return m10;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m20 () {
+ return m20;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m01 () {
+ return m01;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m11 () {
+ return m11;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m21 () {
+ return m21;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m02 () {
+ return m02;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m12 () {
+ return m12;
+ }
+
+ @Override // from AbstractMatrix3
+ public float m22 () {
+ return m22;
+ }
+}
diff --git a/src/main/java/pythagoras/f/Vector3.java b/src/main/java/pythagoras/f/Vector3.java
new file mode 100644
index 0000000..acb198a
--- /dev/null
+++ b/src/main/java/pythagoras/f/Vector3.java
@@ -0,0 +1,206 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.f;
+
+import java.io.Serializable;
+
+/**
+ * A three element vector.
+ */
+public class Vector3 extends AbstractVector3 implements Serializable
+{
+ /** A unit vector in the X+ direction. */
+ public static final IVector3 UNIT_X = new Vector3(1f, 0f, 0f);
+
+ /** A unit vector in the Y+ direction. */
+ public static final IVector3 UNIT_Y = new Vector3(0f, 1f, 0f);
+
+ /** A unit vector in the Z+ direction. */
+ public static final IVector3 UNIT_Z = new Vector3(0f, 0f, 1f);
+
+ /** A vector containing unity for all components. */
+ public static final IVector3 UNIT_XYZ = new Vector3(1f, 1f, 1f);
+
+ /** A normalized version of UNIT_XYZ. */
+ public static final IVector3 NORMAL_XYZ = UNIT_XYZ.normalize();
+
+ /** The zero vector. */
+ public static final IVector3 ZERO = new Vector3(0f, 0f, 0f);
+
+ /** A vector containing the minimum floating point value for all components
+ * (note: the components are -{@link Float#MAX_VALUE}, not {@link Float#MIN_VALUE}). */
+ public static final IVector3 MIN_VALUE =
+ new Vector3(-Float.MAX_VALUE, -Float.MAX_VALUE, -Float.MAX_VALUE);
+
+ /** A vector containing the maximum floating point value for all components. */
+ public static final IVector3 MAX_VALUE =
+ new Vector3(Float.MAX_VALUE, Float.MAX_VALUE, Float.MAX_VALUE);
+
+ /** The components of the vector. */
+ public float x, y, z;
+
+ /**
+ * Creates a vector from three components.
+ */
+ public Vector3 (float x, float y, float z) {
+ set(x, y, z);
+ }
+
+ /**
+ * Creates a vector from an array of values.
+ */
+ public Vector3 (float[] values) {
+ set(values);
+ }
+
+ /**
+ * Copy constructor.
+ */
+ public Vector3 (IVector3 other) {
+ set(other);
+ }
+
+ /**
+ * Creates a zero vector.
+ */
+ public Vector3 () {
+ }
+
+ /**
+ * Computes the cross product of this and the specified other vector, storing the result
+ * in this vector.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 crossLocal (IVector3 other) {
+ return cross(other, this);
+ }
+
+ /**
+ * Negates this vector in-place.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 negateLocal () {
+ return negate(this);
+ }
+
+ /**
+ * Normalizes this vector in-place.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 normalizeLocal () {
+ return normalize(this);
+ }
+
+ /**
+ * Multiplies this vector in-place by a scalar.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 multLocal (float v) {
+ return mult(v, this);
+ }
+
+ /**
+ * Multiplies this vector in-place by another.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 multLocal (IVector3 other) {
+ return mult(other, this);
+ }
+
+ /**
+ * Adds a vector in-place to this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 addLocal (IVector3 other) {
+ return add(other, this);
+ }
+
+ /**
+ * Subtracts a vector in-place from this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 subtractLocal (IVector3 other) {
+ return subtract(other, this);
+ }
+
+ /**
+ * Adds a vector in-place to this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 addLocal (float x, float y, float z) {
+ return add(x, y, z, this);
+ }
+
+ /**
+ * Adds a scaled vector in-place to this one.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 addScaledLocal (IVector3 other, float v) {
+ return addScaled(other, v, this);
+ }
+
+ /**
+ * Linearly interpolates between this and the specified other vector in-place by the supplied
+ * amount.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 lerpLocal (IVector3 other, float t) {
+ return lerp(other, t, this);
+ }
+ /**
+ * Copies the elements of another vector.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 set (IVector3 other) {
+ return set(other.x(), other.y(), other.z());
+ }
+
+ /**
+ * Copies the elements of an array.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 set (float[] values) {
+ return set(values[0], values[1], values[2]);
+ }
+
+ /**
+ * Sets all of the elements of the vector.
+ *
+ * @return a reference to this vector, for chaining.
+ */
+ public Vector3 set (float x, float y, float z) {
+ this.x = x;
+ this.y = y;
+ this.z = z;
+ return this;
+ }
+
+ @Override // from AbstractVector3
+ public float x () {
+ return x;
+ }
+
+ @Override // from AbstractVector3
+ public float y () {
+ return y;
+ }
+
+ @Override // from AbstractVector3
+ public float z () {
+ return z;
+ }
+}
diff --git a/src/main/java/pythagoras/util/NoninvertibleTransformException.java b/src/main/java/pythagoras/util/NoninvertibleTransformException.java
index d7e6a19..f9d6321 100644
--- a/src/main/java/pythagoras/util/NoninvertibleTransformException.java
+++ b/src/main/java/pythagoras/util/NoninvertibleTransformException.java
@@ -8,7 +8,7 @@ package pythagoras.util;
* An exception thrown by {@code Transform} when a request for an inverse transform cannot be
* satisfied.
*/
-public class NoninvertibleTransformException extends java.lang.RuntimeException
+public class NoninvertibleTransformException extends RuntimeException
{
public NoninvertibleTransformException (String s) {
super(s);
diff --git a/src/main/java/pythagoras/util/SingularMatrixException.java b/src/main/java/pythagoras/util/SingularMatrixException.java
new file mode 100644
index 0000000..0687b34
--- /dev/null
+++ b/src/main/java/pythagoras/util/SingularMatrixException.java
@@ -0,0 +1,24 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.util;
+
+/**
+ * Thrown when inversion is attempted on a singular (non-invertible) matrix.
+ */
+public class SingularMatrixException extends RuntimeException
+{
+ /**
+ * Creates a new exception.
+ */
+ public SingularMatrixException () {
+ }
+
+ /**
+ * Creates a new exception with the provided message.
+ */
+ public SingularMatrixException (String message) {
+ super(message);
+ }
+}