/// <summary>
/// Multiplies all path segments in the specified list by the specified matrix. If there are any relative path segments in the
/// list then they will be converted to their absolute counterparts.
/// </summary>
/// <param name="list">list of path segments to transform</param>
/// <param name="matrix">matrix to multiply the path segment coordinates by</param>
/// <returns>transformed list of path segments where all coordinates have been multiplied by the specified matrix</returns>
public static SvgPathSegList MultiplyByMatrix(SvgPathSegList list, SvgMatrix matrix)
{
if (list == null)
{
throw new ArgumentNullException(nameof(list));
}
if (matrix == null)
{
throw new ArgumentNullException(nameof(matrix));
}
if (list.Any(i => RelativePathSegTypes.Contains(i.PathSegType)))
{
list = ConvertToAbsolute(list);
}
var transformer = new SvgPathSegMatrixTransformer(matrix);
return(new SvgPathSegList(list.Select(item => item.Accept(transformer))));
}
/// <summary>
/// Creates a rotation matrix about a given point.
///
/// If optional parameters <see cref="x"/> and <see cref="y"/> are not supplied the operation corresponds to
/// the matrix [cos(a) sin(a) -sin(a) cos(a) 0 0].
///
/// If optional parameters <see cref="x"/> and <see cref="y"/>, the rotate is about the point(x, y) and the operation
/// represents the equivalent of the following specification:
/// translate(x, y) rotate(angle) translate(-x, -y).
/// </summary>
public static SvgMatrix CreateRotate(float angleInDegrees, float?x = null, float?y = null)
{
if (x.HasValue != y.HasValue)
{
throw new ArgumentException();
}
var radians = angleInDegrees * Math.PI / 180f;
var cosA = (float)Math.Cos(radians);
var sinA = (float)Math.Sin(radians);
var rotMatrix = new SvgMatrix(cosA, sinA, -sinA, cosA, 0, 0);
if (x != null)
{
var translate1 = CreateTranslate(x.Value, y.Value);
var translate2 = CreateTranslate(-x.Value, -y.Value);
return(Multiply(translate1, Multiply(rotMatrix, translate2)));
}
return(rotMatrix);
}
private static SvgTransform CreateRotateTransformationFromArgs(string args)
{
// rotate(<rotate-angle> [<cx> <cy>]), which specifies a rotation by <rotate-angle> degrees about a given point.
//
// If optional parameters <cx> and <cy> are not supplied, the rotate is about the origin of the current user coordinate system.
// The operation corresponds to the matrix [cos(a) sin(a) -sin(a) cos(a) 0 0].
//
// If optional parameters<cx> and<cy> are supplied, the rotate is about the point(cx, cy).
// The operation represents the equivalent of the following specification:
// translate(< cx >, < cy >) rotate(< rotate - angle >) translate(-< cx >, -< cy >).
var split = SplitStringOfNumbers(args);
if (split.Length != 1 && split.Length != 3)
{
throw new Exception($"Invalid rotate transformation arguments '{args}'");
}
var angle = float.Parse(split[0]);
var cx = split.Length > 1 ? (float?)float.Parse(split[1]) : null;
var cy = split.Length > 1 ? (float?)float.Parse(split[2]) : null;
var matrix = SvgMatrix.CreateRotate(angle, cx, cy);
return(new SvgTransform(SvgTransformType.Rotate, matrix, angle));
}
/// <summary> /// Multiplies all path segments in the specified list by the specified matrix. If there are any relative path segments in the /// list then they will be converted to their absolute counterparts. /// </summary> /// <param name="list">list of path segments to transform</param> /// <param name="matrix">matrix to multiply the path segment coordinates by</param> /// <returns>transformed list of path segments where all coordinates have been multiplied by the specified matrix</returns> public static SvgPathSegList MultiplyByMatrix(this SvgPathSegList list, SvgMatrix matrix) => SvgPathSegListTransformer.MultiplyByMatrix(list, matrix);
internal SvgTransform(SvgTransformType transformType, SvgMatrix matrix, float angle = 0)
{
Matrix = matrix ?? throw new ArgumentNullException(nameof(matrix));
TransformType = transformType;
Angle = angle;
}
public static void Multiply(SvgMatrix mat, float x, float y, out float resultX, out float resultY)
{
resultX = mat.A * x + mat.C * y + mat.E;
resultY = mat.B * x + mat.D * y + mat.F;
}