/// <summary>
/// Draws the knob indicator.
/// </summary>
/// <param name="Gr">The gr.</param>
/// <param name="rc">The rc.</param>
/// <param name="pos">The position.</param>
/// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
public virtual bool DrawKnobIndicator(Graphics Gr, RectangleF rc, PointF pos)
{
if (this.Knob == null)
{
return(false);
}
RectangleF _rc = rc;
_rc.X = pos.X - 4;
_rc.Y = pos.Y - 4;
_rc.Width = 8;
_rc.Height = 8;
Color cKnob = this.Knob.IndicatorColor;
Color cKnobDark = ZeroitLBColorManager.StepColor(cKnob, 60);
LinearGradientBrush br = new LinearGradientBrush(_rc, cKnobDark, cKnob, 45);
Gr.FillEllipse(br, _rc);
br.Dispose();
return(true);
}
/// <summary>
/// Draw the knob of the control
/// </summary>
/// <param name="Gr">The gr.</param>
/// <param name="rc">The rc.</param>
/// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
public virtual bool DrawKnob(Graphics Gr, RectangleF rc)
{
if (this.Knob == null)
{
return(false);
}
Color cKnob = this.Knob.KnobColor;
Color cKnobDark = ZeroitLBColorManager.StepColor(cKnob, 60);
LinearGradientBrush br = new LinearGradientBrush(rc, cKnob, cKnobDark, 45);
Gr.FillEllipse(br, rc);
br.Dispose();
return(true);
}
/// <summary>
/// Steps the color.
/// </summary>
/// <param name="clr">The color.</param>
/// <param name="alpha">The alpha.</param>
/// <returns>Color.</returns>
public static Color StepColor(Color clr, int alpha)
{
if (alpha == 100)
{
return(clr);
}
byte a = clr.A;
byte r = clr.R;
byte g = clr.G;
byte b = clr.B;
float bg = 0;
int _alpha = Math.Min(alpha, 200);
_alpha = Math.Max(alpha, 0);
double ialpha = ((double)(_alpha - 100.0)) / 100.0;
if (ialpha > 100)
{
// blend with white
bg = 255.0F;
ialpha = 1.0F - ialpha; // 0 = transparent fg; 1 = opaque fg
}
else
{
// blend with black
bg = 0.0F;
ialpha = 1.0F + ialpha; // 0 = transparent fg; 1 = opaque fg
}
r = (byte)(ZeroitLBColorManager.BlendColour(r, bg, ialpha));
g = (byte)(ZeroitLBColorManager.BlendColour(g, bg, ialpha));
b = (byte)(ZeroitLBColorManager.BlendColour(b, bg, ialpha));
return(Color.FromArgb(a, r, g, b));
}