//draw pie slice
public static ARGB[,] DrawSlice(ARGB[,] Target, double startangle, double angletodraw, ARGB color)
{
int sizepiechart = Target.GetLength(0);
SimpleVector oldVec, newVec;
oldVec = new SimpleVector();
newVec = new SimpleVector();
newVec.x = Math.Cos(angletodraw);
newVec.y = Math.Sin(angletodraw);
oldVec.x = Math.Cos(startangle);
oldVec.y = Math.Sin(startangle);
SimpleVector point;
for (int x = 0; x < sizepiechart; x++)
{
for (int y = 0; y < sizepiechart; y++)
{
if (Math.Sqrt(Math.Pow(x - sizepiechart / 2, 2) + Math.Pow(y - sizepiechart / 2, 2)) < sizepiechart / 2)
{
point = new SimpleVector(x - sizepiechart / 2, y - sizepiechart / 2);
if (isCounterClockwise(newVec, point) && !isCounterClockwise(oldVec, point))
{
Target[x, y] = color;
}
}
}
}
return(Target);
}
public static bool isCounterClockwise(SimpleVector line, SimpleVector point)
{
SimpleVector normal = new SimpleVector(-line.y, line.x);
double projection = point.x * line.x + point.y * line.y;
if (projection >= 0)
{
return(true);
}
else
{
return(false);
}
}
