public void GetColumn0_ReturnsColumn0()
{
// Arrange
var mat = new Matrix4f(new Vector4f(1, 0, 0, 0), new Vector4f(2, 0, 0, 0), new Vector4f(3, 0, 0, 0), new Vector4f(4, 0, 0, 0));
// Act
var theRow = mat.Column(0);
// Assert
Assert.That(theRow, Is.EqualTo(new Vector4f(1, 2, 3, 4)));
}
public void GetColumn3_ReturnsColumn3()
{
// Arrange
var mat = new Matrix4f(new Vector4f(0, 0, 0, 1), new Vector4f(0, 0, 0, 2), new Vector4f(0, 0, 0, 3), new Vector4f(0, 0, 0, 4));
// Act
var theRow = mat.Column(3);
// Assert
Assert.That(theRow, Is.EqualTo(new Vector4f(1, 2, 3, 4)));
}
public void GetRow_ReturnsCorrectRow(int index)
{
// Arrange
var vectors = new Vector4f[4];
vectors[index] = new Vector4f(1, 2, 3, 4);
var mat = new Matrix4f(vectors[0], vectors[1], vectors[2], vectors[3]);
// Act
var theRow = mat.Row(index);
// Assert
Assert.That(theRow, Is.EqualTo(new Vector4f(1, 2, 3, 4)));
}
public void Invert_NotInvertible_ThrowsInvalidOperationException()
{
// Arrange
var mat = new Matrix4f(
new Vector4f(1, 2, 3, 4),
new Vector4f(5, 6, 7, 8),
new Vector4f(9, 10, 11, 12),
new Vector4f(13, 14, 15, 16));
// Act
TestDelegate invert = () => mat.Invert();
// Assert
Assert.That(invert, Throws.InvalidOperationException);
}
[Test] // Work in progress
public void Determinant_ReturnsCorrectDeterminant()
{
// Arrange
var mat = new Matrix4f
(
new Vector4f(3, 2, -1, 4),
new Vector4f(2, 1, 5, 7),
new Vector4f(0, 5, 2, -6),
new Vector4f(-1, 2, 1, 0)
);
// Act
var determinant = mat.Determinant();
// Assert
Assert.That(determinant, Is.EqualTo(-418));
}
public void Transpose_ReturnsRowsAsColumns()
{
var mat = new Matrix4f(new Vector4f(1, 2, 3, 4), new Vector4f(1, 2, 3, 4), new Vector4f(1, 2, 3, 4),
new Vector4f(1, 2, 3, 4));
Matrix4f result = mat.Transpose();
Assert.That(result.Column(0), Is.EqualTo(new Vector4f(1, 2, 3, 4)));
Assert.That(result.Column(1), Is.EqualTo(new Vector4f(1, 2, 3, 4)));
Assert.That(result.Column(2), Is.EqualTo(new Vector4f(1, 2, 3, 4)));
Assert.That(result.Column(3), Is.EqualTo(new Vector4f(1, 2, 3, 4)));
}
public void Multiply_Matrix_ReturnsCorrectMatrix()
{
// Arrange
var left = new Matrix4f(
new Vector4f(1, 2, 3, 4),
new Vector4f(5, 6, 7, 8),
new Vector4f(9, 10, 11, 12),
new Vector4f(13, 14, 15, 16));
var right = new Matrix4f(
new Vector4f(21, 22, 23, 24),
new Vector4f(25, 26, 27, 28),
new Vector4f(29, 30, 31, 32),
new Vector4f(33, 34, 35, 36));
// Act
var result = left.Multiply(right);
// Assert
Assert.That(result.Row(0), Is.EqualTo(new Vector4f(650, 740, 830, 920)));
Assert.That(result.Row(1), Is.EqualTo(new Vector4f(762, 868, 974, 1080)));
Assert.That(result.Row(2), Is.EqualTo(new Vector4f(874, 996, 1118, 1240)));
Assert.That(result.Row(3), Is.EqualTo(new Vector4f(986, 1124, 1262, 1400)));
}
public void Invert_ReturnsInvertedMatrix()
{
// Arrange
var mat = new Matrix4f(
new Vector4f(4, 0, 0, 0),
new Vector4f(0, 0, 2, 0),
new Vector4f(0, 1, 2, 0),
new Vector4f(1, 0, 0, 1) );
// Act
var resultMat = mat.Invert();
var results = new[] {resultMat.Row(0), resultMat.Row(1), resultMat.Row(2), resultMat.Row(3)};
// Assert
Assert.That(results, Is.EquivalentTo(new []
{
new Vector4f(0.25f, 0, 0, 0),
new Vector4f(0, -1, 1, 0),
new Vector4f(0, 0.5f, 0, 0),
new Vector4f(-0.25f, 0, 0, 1)
}));
}
public Matrix4f Multiply(Matrix4f rhs)
{
Contract.Requires(rhs != null, "rhs cannot be null.");
Contract.EndContractBlock();
if (rhs == null)
throw new ArgumentNullException("rhs");
var result = new float[4, 4];
for (int i = 0; i < 4; i++)
{
for (int j = 0; j < 4; j++)
{
result[j, i] = System.Numerics.VectorMath.DotProduct(Column(j), rhs.Row(i));
}
}
return new Matrix4f(
new Vector4f(result[0, 0], result[1, 0], result[2, 0], result[3, 0]),
new Vector4f(result[0, 1], result[1, 1], result[2, 1], result[3, 1]),
new Vector4f(result[0, 2], result[1, 2], result[2, 2], result[3, 2]),
new Vector4f(result[0, 3], result[1, 3], result[2, 3], result[3, 3]));
}
