applyGradientRotation function
Implementation
List<num> applyGradientRotation(List<num>? t1, double angle) {
t1 ??= defaultGradientTransform();
final double tx = t1.length > 4 ? t1[4].toDouble() : 0;
final double ty = t1.length > 5 ? t1[5].toDouble() : 0;
final rads = angle * pi / 180;
final cosA = cos(rads);
final sinA = sin(rads);
final vec_math.Matrix3 matrix =
vec_math.Matrix3(cosA, sinA, tx, -sinA, cosA, ty, 0, 0, 1);
final List<num> list = List.filled(9, 0);
matrix.copyIntoArray(list);
return list.take(6).toList();
}