private static void innerDrawCircle(Vector2 center, int radius, Color color, bool filled, int thickness)
{
bool containsKeyRadius = CirclesCache.ContainsKey(radius);
if (containsKeyRadius)
{
foreach (Circle c in CirclesCache[radius])
{
if (c.Filled == filled && (filled || c.Thickness == thickness))
{
SpriteBatch.Draw(c.Texture, center, null, color, 0, new Vector2(radius + 1, radius + 1), 1, SpriteEffects.None, 0);
return;
}
}
}
int outerRadius = radius * 2 + 2;
Texture2D texture = new Texture2D(Primitives.GraphicsDevice, outerRadius, outerRadius);
if (filled)
{
thickness = radius + 1;
}
Color[] data = new Color[outerRadius * outerRadius];
for (int i = 0; i < data.Length; i++)
{
data[i] = Color.Transparent;
}
double angleStep = 0.5f / radius;
int lowpoint = radius - thickness;
for (double angle = 0; angle < Math.PI * 2; angle += angleStep)
{
for (int i = radius; i > lowpoint; i--)
{
int x = (int)Math.Round(radius + i * Math.Cos(angle));
int y = (int)Math.Round(radius + i * Math.Sin(angle));
data[y * outerRadius + x + 1] = color;
}
}
texture.SetData(data);
if (containsKeyRadius)
{
CirclesCache[radius].Add(new Circle(texture, radius, filled, thickness));
}
else
{
CirclesCache.Add(radius, new List <Circle>(new Circle[] { new Circle(texture, radius, filled, thickness) }));
}
SpriteBatch.Draw(texture, center, null, color, 0, new Vector2(radius + 1, radius + 1), 1, SpriteEffects.None, 0);
}
/// <summary>
/// Clears all cached Circle textures. This will clear space from memory, but drawing circles will take longer.
/// </summary>
public static void ClearCircleCache()
{
CirclesCache.Clear();
GC.Collect();
}
