private void CreatePolygonPath()
{
var points = (float)Math.Floor(_pointsAnimation.Value.Value);
double currentAngle = _rotationAnimation?.Value ?? 0f;
// Start at +y instead of +x
currentAngle -= 90;
// convert to radians
currentAngle = MathExt.ToRadians(currentAngle);
// adjust current angle for partial points
var anglePerPoint = (float)(2 * Math.PI / points);
var roundedness = _outerRoundednessAnimation.Value.Value / 100f;
var radius = _outerRadiusAnimation.Value.Value;
float x;
float y;
x = (float)(radius * Math.Cos(currentAngle));
y = (float)(radius * Math.Sin(currentAngle));
_path.MoveTo(x, y);
currentAngle += anglePerPoint;
var numPoints = (int)Math.Ceiling(points);
for (var i = 0; i < numPoints; i++)
{
var previousX = x;
var previousY = y;
x = (float)(radius * Math.Cos(currentAngle));
y = (float)(radius * Math.Sin(currentAngle));
if (roundedness != 0)
{
var cp1Theta = (float)(Math.Atan2(previousY, previousX) - Math.PI / 2f);
var cp1Dx = (float)Math.Cos(cp1Theta);
var cp1Dy = (float)Math.Sin(cp1Theta);
var cp2Theta = (float)(Math.Atan2(y, x) - Math.PI / 2f);
var cp2Dx = (float)Math.Cos(cp2Theta);
var cp2Dy = (float)Math.Sin(cp2Theta);
var cp1X = radius * roundedness * PolygonMagicNumber * cp1Dx;
var cp1Y = radius * roundedness * PolygonMagicNumber * cp1Dy;
var cp2X = radius * roundedness * PolygonMagicNumber * cp2Dx;
var cp2Y = radius * roundedness * PolygonMagicNumber * cp2Dy;
_path.CubicTo(previousX - cp1X, previousY - cp1Y, x + cp2X, y + cp2Y, x, y);
}
else
{
_path.LineTo(x, y);
}
currentAngle += anglePerPoint;
}
var position = _positionAnimation.Value;
if (position != null)
{
_path.Offset(position.X, position.Y);
}
_path.Close();
}
private void CreateStarPath()
{
var points = _pointsAnimation.Value.Value;
double currentAngle = _rotationAnimation?.Value ?? 0f;
// Start at +y instead of +x
currentAngle -= 90;
// convert to radians
currentAngle = MathExt.ToRadians(currentAngle);
// adjust current angle for partial points
var anglePerPoint = (float)(2 * Math.PI / points);
var halfAnglePerPoint = anglePerPoint / 2.0f;
var partialPointAmount = points - (int)points;
if (partialPointAmount != 0)
{
currentAngle += halfAnglePerPoint * (1f - partialPointAmount);
}
var outerRadius = _outerRadiusAnimation.Value.Value;
var innerRadius = _innerRadiusAnimation.Value.Value;
var innerRoundedness = 0f;
if (_innerRoundednessAnimation != null)
{
innerRoundedness = _innerRoundednessAnimation.Value.Value / 100f;
}
var outerRoundedness = 0f;
if (_outerRoundednessAnimation != null)
{
outerRoundedness = _outerRoundednessAnimation.Value.Value / 100f;
}
float x;
float y;
float partialPointRadius = 0;
if (partialPointAmount != 0)
{
partialPointRadius = innerRadius + partialPointAmount * (outerRadius - innerRadius);
x = (float)(partialPointRadius * Math.Cos(currentAngle));
y = (float)(partialPointRadius * Math.Sin(currentAngle));
_path.MoveTo(x, y);
currentAngle += anglePerPoint * partialPointAmount / 2f;
}
else
{
x = (float)(outerRadius * Math.Cos(currentAngle));
y = (float)(outerRadius * Math.Sin(currentAngle));
_path.MoveTo(x, y);
currentAngle += halfAnglePerPoint;
}
// True means the line will go to outer radius. False means inner radius.
var longSegment = false;
var numPoints = (int)Math.Ceiling(points) * 2;
for (var i = 0; i < numPoints; i++)
{
var radius = longSegment ? outerRadius : innerRadius;
var dTheta = halfAnglePerPoint;
if (partialPointRadius != 0 && i == numPoints - 2)
{
dTheta = anglePerPoint * partialPointAmount / 2f;
}
if (partialPointRadius != 0 && i == numPoints - 1)
{
radius = partialPointRadius;
}
var previousX = x;
var previousY = y;
x = (float)(radius * Math.Cos(currentAngle));
y = (float)(radius * Math.Sin(currentAngle));
if (innerRoundedness == 0 && outerRoundedness == 0)
{
_path.LineTo(x, y);
}
else
{
var cp1Theta = (float)(Math.Atan2(previousY, previousX) - Math.PI / 2f);
var cp1Dx = (float)Math.Cos(cp1Theta);
var cp1Dy = (float)Math.Sin(cp1Theta);
var cp2Theta = (float)(Math.Atan2(y, x) - Math.PI / 2f);
var cp2Dx = (float)Math.Cos(cp2Theta);
var cp2Dy = (float)Math.Sin(cp2Theta);
var cp1Roundedness = longSegment ? innerRoundedness : outerRoundedness;
var cp2Roundedness = longSegment ? outerRoundedness : innerRoundedness;
var cp1Radius = longSegment ? innerRadius : outerRadius;
var cp2Radius = longSegment ? outerRadius : innerRadius;
var cp1X = cp1Radius * cp1Roundedness * PolystarMagicNumber * cp1Dx;
var cp1Y = cp1Radius * cp1Roundedness * PolystarMagicNumber * cp1Dy;
var cp2X = cp2Radius * cp2Roundedness * PolystarMagicNumber * cp2Dx;
var cp2Y = cp2Radius * cp2Roundedness * PolystarMagicNumber * cp2Dy;
if (partialPointAmount != 0)
{
if (i == 0)
{
cp1X *= partialPointAmount;
cp1Y *= partialPointAmount;
}
else if (i == numPoints - 1)
{
cp2X *= partialPointAmount;
cp2Y *= partialPointAmount;
}
}
_path.CubicTo(previousX - cp1X, previousY - cp1Y, x + cp2X, y + cp2Y, x, y);
}
currentAngle += dTheta;
longSegment = !longSegment;
}
var position = _positionAnimation.Value;
if (position != null)
{
_path.Offset(position.X, position.Y);
}
_path.Close();
}
public void AddPathSegment(SKPath canvasPathBuilder, ref bool closed)
{
canvasPathBuilder.ArcTo(_endPoint.ToSkPoint(), (float)MathExt.ToRadians(_sweepAngle), SKPathArcSize.Small, SKPathDirection.Clockwise, new SKPoint(_a, _b));
closed = false;
}
public override ScaleXy GetValue(IKeyframe <ScaleXy> keyframe, float keyframeProgress)
{
if (keyframe.StartValue == null || keyframe.EndValue == null)
{
throw new InvalidOperationException("Missing values for keyframe.");
}
var startTransform = keyframe.StartValue;
var endTransform = keyframe.EndValue;
return(new ScaleXy(MathExt.Lerp(startTransform.ScaleX, endTransform.ScaleX, keyframeProgress), MathExt.Lerp(startTransform.ScaleY, endTransform.ScaleY, keyframeProgress)));
}
public void AddPathSegment(ref CanvasGeometry geometry, CanvasPathBuilder canvasPathBuilder, CanvasDevice device, ref bool closed)
{
canvasPathBuilder.AddArc(_endPoint, _a, _b, (float)MathExt.ToRadians(_sweepAngle), CanvasSweepDirection.Clockwise, CanvasArcSize.Small);
closed = false;
}
