/// <summary>
/// Berechnet die Position eines Punkts, der um einen angegeben Punkt entlang einer Achse rotiert wird
/// </summary>
/// <param name="point">Mittelpunkt der Rotation</param>
/// <param name="distance">Distanz zum Mittelpunkt</param>
/// <param name="degrees">Grad der Rotation</param>
/// <param name="plane">Achse der Rotation (Standard: Y)</param>
/// <returns>Position des rotierten Punkts</returns>
public static Vector3 CalculateRotationAroundPointOnAxis(Vector3 point, float distance, float degrees, Plane plane = Plane.Y)
{
float radians = MathHelper.DegreesToRadians(degrees % 360);
Matrix4.CreateTranslation(ref point, out translationPointMatrix);
if (plane == Plane.X)
{
Matrix4.CreateRotationX(radians, out rotationMatrix);
Matrix4.CreateTranslation(0, 0, distance, out translationMatrix);
}
else if (plane == Plane.Y)
{
Matrix4.CreateRotationY(radians, out rotationMatrix);
Matrix4.CreateTranslation(0, 0, distance, out translationMatrix);
}
else if (plane == Plane.Z)
{
Matrix4.CreateRotationZ(radians, out rotationMatrix);
Matrix4.CreateTranslation(0, distance, 0, out translationMatrix);
}
else if (plane == Plane.Camera)
{
if (KWEngine.CurrentWorld != null)
{
Vector3 camLookAt;
if (KWEngine.CurrentWorld.IsFirstPersonMode)
{
camLookAt = KWEngine.CurrentWorld.GetFirstPersonObject().GetLookAtVector();
}
else
{
camLookAt = KWEngine.CurrentWorld.GetCameraLookAtVector();
}
rotationMatrix = HelperMatrix.CreateRotationMatrixForAxisAngle(ref camLookAt, ref radians);
Vector3 cross = Vector3.Cross(camLookAt, KWEngine.WorldUp);
Matrix4.CreateTranslation(-cross.X, -cross.Y, -cross.Z, out translationMatrix);
}
else
{
HelperGeneral.ShowErrorAndQuit("HelperRotation::CalculateRotationAroundPointOnAxis()", "CurrentWorld is not set. Cannot rotate around a camera axis that does not exist.");
return(Vector3.Zero);
}
}
Matrix4.Mult(ref translationMatrix, ref rotationMatrix, out tempMatrix);
Matrix4.Mult(ref tempMatrix, ref translationPointMatrix, out spinMatrix);
Vector3.TransformPosition(ref zeroVector, ref spinMatrix, out finalTranslationPoint);
return(finalTranslationPoint);
}
/// <summary>
/// Berechnet die Position eines Punkts, der um einen angegeben Punkt entlang einer Achse rotiert wird
/// </summary>
/// <param name="point">Mittelpunkt der Rotation</param>
/// <param name="distance">Distanz zum Mittelpunkt</param>
/// <param name="degrees">Grad der Rotation</param>
/// <param name="axis">Achse der Rotation (normalisiert!)</param>
/// <returns>Position des rotierten Punkts</returns>
public static Vector3 CalculateRotationAroundPointOnAxis(Vector3 point, float distance, float degrees, Vector3 axis)
{
float radians = MathHelper.DegreesToRadians(degrees % 360);
Matrix4.CreateTranslation(ref point, out translationPointMatrix);
rotationMatrix = HelperMatrix.CreateRotationMatrixForAxisAngle(ref axis, ref radians);
Vector3 cross = Vector3.Cross(axis, KWEngine.WorldUp);
Matrix4.CreateTranslation(-cross.X, -cross.Y, -cross.Z, out translationMatrix);
Matrix4.Mult(ref translationMatrix, ref rotationMatrix, out tempMatrix);
Matrix4.Mult(ref tempMatrix, ref translationPointMatrix, out spinMatrix);
Vector3.TransformPosition(ref zeroVector, ref spinMatrix, out finalTranslationPoint);
return(finalTranslationPoint);
}