/// <summary>
/// Creates a new 4x4 perspective matrix
/// </summary>
/// <param name="focalLength"></param>
/// <returns></returns>
public static ASMATRIX4 CreatePerspectiveMatrix(double focalLength)
{
// Reset the matrix to an identity matrix
var m = new ASMATRIX4();
// Create the perspective matrix
m.Matrix[3].Points[2] = 1 / focalLength;
m.Matrix[3].Points[3] = 0;
return(m);
}
/// <summary>
/// Builds a transaltion matrix and returns it to the caller
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="z"></param>
/// <returns></returns>
public static ASMATRIX4 CreateScalingMatrix(double x, double y, double z)
{
// Zero the matrix
var m = new ASMATRIX4();
// Scale the matrix
m.Matrix[0].Points[0] = x;
m.Matrix[1].Points[1] = y;
m.Matrix[2].Points[2] = z;
return(m);
}
/// <summary>
/// Builds a transaltion matrix and returns it to the caller
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="z"></param>
/// <returns></returns>
public static ASMATRIX4 CreateTranslationMatrix(double x, double y, double z)
{
// reset to identity matrix
var m = new ASMATRIX4();
// Set the translation matrix
m.Matrix[0].Points[3] = x;
m.Matrix[1].Points[3] = y;
m.Matrix[2].Points[3] = z;
return(m);
}
/// <summary>
/// Transforms the face by a transformation matrix, this will allow
/// the mesh to be scaled
/// </summary>
/// <param name="matrix"></param>
/// <returns></returns>
public ASFace TransformFace(ASMATRIX4 matrix)
{
var transformedFace = new ASFace();
for (var i = 0; i < 3; i++)
{
transformedFace.m_points[i] = m_points[i].TransformVector(matrix);
transformedFace.m_points[i] = transformedFace.m_points[i].Rescale();
}
return(transformedFace);
}
/// <summary>
/// Creates a rotation matrix around the Z origin, given the angle
/// in degree
/// </summary>
/// <param name="radians"></param>
private static ASMATRIX4 CreateRotationAroundZ(double radians)
{
// See if the angle is valid, if not set default
CheckAngle(radians, out radians);
// Zero the Matrix
var m = new ASMATRIX4();
// Create the X Rotation Matrix
m.Matrix[0].Points[0] = Math.Cos(radians);
m.Matrix[0].Points[1] = Math.Sin(radians);
m.Matrix[1].Points[0] = -(Math.Sin(radians));
m.Matrix[1].Points[1] = Math.Cos(radians);
return(m);
}
/// <summary>
/// Transform the vector by a matrix
/// </summary>
/// <param name="m"></param>
public ASVECTOR3 TransformVector(ASMATRIX4 m)
{
var newPoint = new ASVECTOR3();
// Multiply rows by cols to get the new vector
for (var col = 0; col < 3; col++)
{
double total = 0;
for (var row = 0; row < 3; row++)
{
total = total + points[row] * m.Matrix[col].Points[row];
}
}
return(newPoint);
}
/// <summary>
/// Multiply two matrices together to get the cross product
/// </summary>
/// <param name="mA"></param>
/// <param name="mB"></param>
/// <returns></returns>
public static ASMATRIX4 operator *(ASMATRIX4 mA, ASMATRIX4 mB)
{
// Creates a new zeroed output matrix
var m = new ASMATRIX4();
// Multiply the two matrixes together and return the output matrix
for (var i = 0; i < 4; i++)
{
for (var j = 0; j < 4; j++)
{
m.Matrix[i].Points[j] =
(mB.Matrix[i].Points[0] * mA.Matrix[0].Points[j]) +
(mB.Matrix[i].Points[1] * mA.Matrix[1].Points[j]) +
(mB.Matrix[i].Points[2] * mA.Matrix[2].Points[j]) +
(mB.Matrix[i].Points[3] * mA.Matrix[3].Points[j]);
}
}
return(m);
}
/// <summary>
/// Transform the vector by a matrix
/// </summary>
/// <param name="m"></param>
public ASVECTOR4 TransformVector(ASMATRIX4 m)
{
return(m * this);
}
