protected override List <Point2D> GeneratePoint2DList(Parabola para)
{
List <Point2D> list = new List <Point2D>();
int a = para.a;
int b = para.b;
int aSign = a < 0 ? -1 : 1;
int bSign = b < 0 ? -1 : 1;
int x = 0;
int y = 0;
int xprev = x;
int yprev = y;
int yInc = -aSign * bSign;
// First half
int p = -2 * yInc * a - b;
while (Math.Abs(2 * a * x) < Math.Abs(b))
{
if (para.orientation == Orientation.Vertical)
{
list.Add(new Point2D(x, y));
}
else
{
list.Add(new Point2D(y, -x));
}
xprev = x;
yprev = y;
if ((b > 0 && p > 0) || (b < 0 && p < 0))
{
p += yInc * -2 * a * (2 * x + 3) - 2 * b;
y += yInc;
}
else
{
p += yInc * -2 * a * (2 * x + 3);
}
x += 1;
}
// Second half
x = xprev;
y = yprev;
p = -2 * b * (y + yInc) - a * (2 * x * x + 2 * x + 1);
while (y * yInc <= para.limit * yInc)
{
if (para.orientation == Orientation.Vertical)
{
list.Add(new Point2D(x, y));
}
else
{
list.Add(new Point2D(y, -x));
}
if ((a > 0 && p > 0) || (a < 0 && p < 0))
{
p += -2 * b * yInc - 2 * a * (2 * x + 2);
x += 1;
}
else
{
p += -2 * b * yInc;
}
y += yInc;
}
if (para.orientation == Orientation.Vertical)
{
list = GenerateOnYSymmetricPoint2D(list, para.pivot);
}
else
{
list = GenerateOnXSymmetricPoint2D(list, para.pivot);
}
return(list);
}
protected override List <Point2D> GeneratePoint2DList(Parabola para)
{
List <Point2D> list = new List <Point2D>();
int a = para.a;
int b = para.b;
int aSign = a < 0 ? -1 : 1;
int bSign = b < 0 ? -1 : 1;
int x = 0;
int y = 0;
int xprev = x;
int yprev = y;
int yInc = -aSign * bSign;
// First half
while (Math.Abs(2 * a * x) < Math.Abs(b))
{
if (para.orientation == Orientation.Vertical)
{
list.Add(new Point2D(x, y));
}
else
{
list.Add(new Point2D(y, -x));
}
xprev = x;
yprev = y;
x += 1;
y = (int)Math.Round(-a * x * x / (double)b);
}
// Second half
x = xprev;
y = yprev;
while (y * yInc <= para.limit * yInc)
{
if (para.orientation == Orientation.Vertical)
{
list.Add(new Point2D(x, y));
}
else
{
list.Add(new Point2D(y, -x));
}
y += yInc;
x = (int)Math.Round(Math.Sqrt(-y * b * 1.0 / a));
}
if (para.orientation == Orientation.Vertical)
{
list = GenerateOnYSymmetricPoint2D(list, para.pivot);
}
else
{
list = GenerateOnXSymmetricPoint2D(list, para.pivot);
}
return(list);
}
protected override List <Point2D> GeneratePoint2DList(Parabola para)
{
throw new NotImplementedException();
}
protected abstract List <Point2D> GeneratePoint2DList(Parabola para);
protected override List <Point2D> GeneratePoint2DList(Parabola para)
{
List <Point2D> list = new List <Point2D>();
int a = para.a;
int b = para.b;
if (b > 0)
{
a = -a;
b = -b;
}
int aSign = a < 0 ? -1 : 1;
int x = 0;
int y = 0;
int xprev = x;
int yprev = y;
int yInc = aSign;
// First half
int p = 2 * yInc * a + b;
while (Math.Abs(2 * a * x) < Math.Abs(b) && Math.Abs(y) < Math.Abs(para.limit))
{
if (para.orientation == Orientation.Vertical)
{
list.Add(new Point2D(x, y));
}
else
{
list.Add(new Point2D(y, -x));
}
xprev = x;
yprev = y;
if (p > 0)
{
p += yInc * 2 * a * (2 * x + 3) + 2 * b;
y += yInc;
}
else
{
p += yInc * 2 * a * (2 * x + 3);
}
x += 1;
}
// Second half
x = xprev;
y = yprev;
if (a > 0)
{
a = -a;
b = -b;
}
p = 4 * a * x * (x + 1) + a + 4 * b * (y + yInc);
while (y * yInc <= para.limit * yInc)
{
if (para.orientation == Orientation.Vertical)
{
list.Add(new Point2D(x, y));
}
else
{
list.Add(new Point2D(y, -x));
}
if (p > 0)
{
p += 4 * a * (2 * x + 2) + 4 * b * yInc;
x += 1;
}
else
{
p += 4 * b * yInc;
}
y += yInc;
}
if (para.orientation == Orientation.Vertical)
{
list = GenerateOnYSymmetricPoint2D(list, para.pivot);
}
else
{
list = GenerateOnXSymmetricPoint2D(list, para.pivot);
}
return(list);
}
