public override void Draw()
{
for (int i = 0; i < lineverts.Length; i++)
{
lineverts[i].Color = GlobalLineColor.GetValueOrDefault(Color.Black);
}
for (int i = 0; i < vertices.Length; i++)
{
vertices[i].Color = GlobalFillColor.GetValueOrDefault(Color.Transparent);
}
foreach (EffectPass pass in BasicEffect.CurrentTechnique.Passes)
{
pass.Apply();
BasicEffect.GraphicsDevice.DrawUserPrimitives <VertexPositionColor>(PrimitiveType.TriangleList, vertices, 0, 51, VertexPositionColor.VertexDeclaration);
BasicEffect.GraphicsDevice.DrawUserPrimitives <VertexPositionColor>(PrimitiveType.LineStrip, lineverts, 0, lineverts.Length - 1);
}
}
// new input for painting color.
//public Color FillColor;
//public Color LineColor;
public CircleAnnotation(float radius, Vector3 startPosition, Vector3 normal)
{
Vector3 b1 = Vector3.Cross(normal, Vector3.UnitY);
float length = b1.Length();
if (length < 0.05)
{
b1 = Vector3.Cross(normal, Vector3.UnitX);
b1.Normalize();
}
else
{
b1 = b1 * (1f / length);
}
Vector3 b2 = Vector3.Cross(b1, normal);
vertices = new VertexPositionColor[153];
//new code to draw triangle strips
vertices[0].Position = startPosition;
vertices[0].Color = GlobalFillColor.GetValueOrDefault(Color.Black);
for (int i = 1; i < vertices.Length - 1; i++)
{
if (i % 3 == 0)
{
vertices[i].Position = startPosition;
vertices[i].Color = GlobalFillColor.GetValueOrDefault(Color.Black);
}
else if ((i >= 3) && (vertices[i - 1].Position == startPosition))
{
vertices[i].Position = vertices[i - 2].Position;
//vertices[i].Color = GlobalFillColor.GetValueOrDefault(Color.Transparent);
}
else
{
float angle = (float)(((float)i / (vertices.Length - 1)) * Math.PI * 2);
vertices[i].Position = (b1 * (float)Math.Cos(angle) * radius) + (b2 * (float)Math.Sin(angle) * radius) + startPosition;
//vertices[i].Color = GlobalFillColor.GetValueOrDefault(Color.Transparent);
}
}
vertices[vertices.Length - 1] = vertices[1];
vertices[vertices.Length - 2] = vertices[149];
vertices[vertices.Length - 3] = vertices[0];
lineverts = new VertexPositionColor[50];
for (int i = 0; i < lineverts.Length - 1; i++)
{
float angle = (float)(((float)i / (lineverts.Length - 1)) * Math.PI * 2);
lineverts[i].Position = (b1 * (float)Math.Cos(angle) * radius) + (b2 * (float)Math.Sin(angle) * radius) + startPosition;
//lineverts[i].Color = GlobalLineColor.GetValueOrDefault(Color.Transparent);
}
lineverts[lineverts.Length - 1] = lineverts[0];
}