/// <summary>
/// Snap rotate to some angle. Preserve scale and translation.
/// </summary>
/// <param name="mat"></param>
/// <param name="angle">__ANGLE IS IN DEGREES__</param>
/// <returns></returns>
public static d2d.Matrix eSnapRotate(this d2d.Matrix mat, double angle)
{
// Graphics tries to work opposite of OpenGL, in Drawing2D:
// PRE - multiply for local
// post -multiply for global
var curmat = mat.Elements;
// get the vector components.
var x_axis = new ai.Vector2D(curmat[0], curmat[1]);
var y_axis = new ai.Vector2D(curmat[2], curmat[3]);
// Get the scale of current matrix
double x_len = x_axis.Length();
double y_len = y_axis.Length();
var newmat = new d2d.Matrix();
// Preserve scale and translation
// This means: v*M = v*(S * R * T)
newmat.Scale((float)x_len, (float)y_len);
newmat.Rotate((float)angle);
newmat.Translate(curmat[4], curmat[5]);
return(newmat.Clone());
}
/// <summary>
/// Rescale the matrix. Preserve rotation and translation.
/// </summary>
/// <param name="mat"></param>
/// <returns></returns>
public static d2d.Matrix eSnapScale(this d2d.Matrix mat, double scale = 1.0)
{
var curmat = mat.Elements;
// normalise the x and y axis to set scale to 1.0f
var x_axis = new ai.Vector2D(curmat[0], curmat[1]);
var y_axis = new ai.Vector2D(curmat[2], curmat[3]);
x_axis.Normalize();
y_axis.Normalize();
// scale the axis
x_axis.X *= (float)scale;
x_axis.Y *= (float)scale;
y_axis.X *= (float)scale;
y_axis.Y *= (float)scale;
// make new matrix with scale of 1.0f
// Do not change the translation
var newmat = new d2d.Matrix(x_axis[0], x_axis[1]
, y_axis[0], y_axis[1]
, curmat[4], curmat[5]
);
return(newmat.Clone());
}
public static OpenTK.Vector2 ToOpenTKVector2(this Assimp.Vector2D vec2)
{
return(new OpenTK.Vector2(vec2.X, vec2.Y));
}
public static Vector2 ToNumerics(this Ai.Vector2D value) => new Vector2(value.X, value.Y);
public static Vector2 ToNumerics(this Ai.Vector2D value)
{
return(new Vector2(value.X, value.Y));
}