public static IEnumerable <GsVector> CreateArc(float cx, float cy, float width, float height, int startAngle, int sweepAngle)
{
int endAngle = startAngle + sweepAngle;
int sign = Math.Sign(endAngle - startAngle);
int negsign = -sign;
int d = sign * AngleIncrement;
for (int angle = startAngle; angle.CompareTo(endAngle).Equals(negsign); angle += d)
{
yield return(new GsVector
{
X = cx + width * GsMath.Cos(angle),
Y = cy + height * GsMath.Sin(angle),
});
}
}
public static GsVector[] CreateEllipse(float h, float k, float width, float height, int slices = DefaultSlices)
{
// create a list of points of the circle
float max = GsMath.TwoPi;
float step = max / (float)slices;
List <GsVector> vectors = new List <GsVector>();
for (float t = 0.0f; t < max; t += step)
{
float x = (float)(h + width * GsMath.Cos(t));
float y = (float)(k + height * GsMath.Sin(t));
vectors.Add(new GsVector(x, y));
}
vectors.Add(vectors[0]);
// return the points
return(vectors.ToArray());
}
public static GsColor Darken(this GsColor color, float amt = 0.5f)
{
return(GsMath.Lerp(color, GsColor.Black, amt));
}
public static GsColor Lighten(this GsColor color, float amt = 0.5f)
{
return(GsMath.Lerp(color, GsColor.White, amt));
}