Rotation Matrix given angle and point in X,Y,Z

Question

I am doing image manipulation and I want to rotate all of the pixels in xyz space based on an angle, the origin, and an x,y, and z coordinate.

I just need to setup t

Answer 1

Use the Matrix3D Structure (MSDN) - Represents a 4 x 4 matrix used for transformations in 3-D space

Take a look here for a tutorial: Building a 3D Engine

Essentially, matrices are built for X, Y, and Z rotations and then you can multiply the rotations in any order.

public static Matrix3D NewRotateAroundX(double radians)
{
    var matrix = new Matrix3D();
    matrix._matrix[1, 1] = Math.Cos(radians);
    matrix._matrix[1, 2] = Math.Sin(radians);
    matrix._matrix[2, 1] = -(Math.Sin(radians));
    matrix._matrix[2, 2] = Math.Cos(radians);
    return matrix;
}
public static Matrix3D NewRotateAroundY(double radians)
{
    var matrix = new Matrix3D();
    matrix._matrix[0, 0] = Math.Cos(radians);
    matrix._matrix[0, 2] = -(Math.Sin(radians));
    matrix._matrix[2, 0] = Math.Sin(radians);
    matrix._matrix[2, 2] = Math.Cos(radians);
    return matrix;
}
public static Matrix3D NewRotateAroundZ(double radians)
{
    var matrix = new Matrix3D();
    matrix._matrix[0, 0] = Math.Cos(radians);
    matrix._matrix[0, 1] = Math.Sin(radians);
    matrix._matrix[1, 0] = -(Math.Sin(radians));
    matrix._matrix[1, 1] = Math.Cos(radians);
    return matrix;
}