public CircleSegment FindSegment(float dX, float dY)
{
double rad = Math.Sqrt(dX * dX + dY * dY);
double angle = SysUtils.RadiansToDegrees(Math.Atan2(dY, dX));
if (angle <= -90)
{
angle += 360.0f;
}
CircleSegment result = null;
int numberOfSegments = fSegments.Count;
for (int i = 0; i < numberOfSegments; i++)
{
CircleSegment segment = fSegments[i];
double startAng = segment.StartAngle;
double endAng = startAng + segment.WedgeAngle;
if ((segment.IntRad <= rad && rad < segment.ExtRad) &&
(startAng <= angle && angle < endAng))
{
result = segment;
break;
}
}
return(result);
}
public void GfxHelper_Tests()
{
Assert.AreEqual(57.295779513, SysUtils.RadiansToDegrees(1.0), 0.0000000001);
Assert.AreEqual(1.0, SysUtils.DegreesToRadians(57.295779513), 0.0000000001);
Assert.AreEqual(2.0, SysUtils.ZoomToFit(50, 20, 100, 50));
Assert.AreEqual(3.0, SysUtils.ZoomToFit(15, 40, 45, 120));
Assert.AreEqual(1.0, SysUtils.ZoomToFit(0, 40, 45, 120));
Assert.AreEqual(1.0, SysUtils.ZoomToFit(15, 0, 45, 120));
}
public override void DrawArcText(string text, float centerX, float centerY, float radius,
float startAngle, float wedgeAngle,
bool inside, bool clockwise, IFont font, IBrush brush)
{
ExtSizeF size = GetTextSize(text, font);
radius = radius + size.Height / 2.0f;
float textAngle = Math.Min((float)SysUtils.RadiansToDegrees((size.Width * 1.75f) / radius), wedgeAngle);
float deltaAngle = (wedgeAngle - textAngle) / 2.0f;
if (clockwise)
{
startAngle += deltaAngle;
}
else
{
startAngle += wedgeAngle - deltaAngle;
}
startAngle = -startAngle;
Matrix previousTransformation = fCanvas.Transform;
for (int i = 0; i < text.Length; ++i)
{
float offset = (textAngle * ((float)(i) / text.Length));
float angle = clockwise ? startAngle - offset : startAngle + offset;
double radAngle = angle * (Math.PI / 180.0d);
float x = (float)(centerX + Math.Cos(radAngle) * radius);
float y = (float)(centerY - Math.Sin(radAngle) * radius);
float charRotation = 90 - (inside ? angle : angle + 180);
charRotation *= (float)(Math.PI / 180.0f);
float cosine = (float)(Math.Cos(charRotation));
float sine = (float)(Math.Sin(charRotation));
Matrix m = new Matrix(cosine, sine, -sine, cosine, x, y);
m.Multiply(previousTransformation, MatrixOrder.Append);
fCanvas.Transform = m;
string chr = new string(text[i], 1);
DrawString(chr, font, brush, 0, 0);
}
fCanvas.Transform = previousTransformation;
}