Custom-drawn CheckBox and RadioButton

My take on a drop-in replacement for custom-drawn CheckBox and RadioButton controls:

	internal class CheckBoxEx : CheckBox
	{
	private const float factor = 0.6f;
	private const int check = 2;
	public Color DisableFore = SystemColors.GrayText;
	protected override void OnPaint( PaintEventArgs pevent )
	{
	base.OnPaint( pevent );
	// To clear the background, it is necessary to use a non-transparent color and
	// this type of controls usually are, so fetch the first parent's that is not
	var backColor = BackColor;
	while( backColor.A == 0 )
	{
	if( Parent == null )
	{
	break;
	}
	backColor = Parent.BackColor;
	}
	if( backColor.A == 0 )
	{
	// The back color is still transparent, so max the alpha component
	backColor = Color.FromArgb( 255, backColor.R, backColor.G, backColor.B );
	}
	pevent.Graphics.Clear( backColor );
	// Calculate the size of the box by using a large default character (since there could be no text
	// in the control) and neither that ClientRectangle or pevent.ClipRectangle might have a valid value
	var height = TextRenderer.MeasureText( pevent.Graphics, "X", Font ).Height;
	var boxSide = (int)( height * factor );
	var boxFrame = new Rectangle( 0, ( height - boxSide ) / 2, boxSide, boxSide );
	var textFrame = new Rectangle( boxFrame.Right + 2, 0, ClientRectangle.Width - boxFrame.Right - 2, height );
	if( Text.Length == 0 )
	{
	// The box cannot be aligned with non-existing text
	boxFrame.Y = 0;
	}
	// Draw box
	using var backBrush = new SolidBrush( BackColor );
	using var foreBrush = new SolidBrush( ForeColor );
	using var forePen = new Pen( ForeColor );
	if( Enabled == false )
	{
	forePen.Color = foreBrush.Color = DisableFore;
	}
	pevent.Graphics.FillRectangle( backBrush, boxFrame );
	pevent.Graphics.DrawRectangle( forePen, boxFrame );
	if( Checked == true )
	{
	boxFrame.Offset( check, check );
	boxFrame.Width -= check + 1;
	boxFrame.Height -= check + 1;
	pevent.Graphics.FillRectangle( foreBrush, boxFrame );
	}
	// Draw text
	if( Text.Length != 0 )
	{
	using var sf = new StringFormat
	{
	Alignment = StringAlignment.Near,
	LineAlignment = StringAlignment.Center
	};
	pevent.Graphics.SmoothingMode = SmoothingMode.HighQuality;
	TextRenderer.DrawText( pevent.Graphics,
	Text,
	Font,
	textFrame,
	foreBrush.Color,
	TextFormatFlags.Top | TextFormatFlags.Left );
	pevent.Graphics.SmoothingMode = SmoothingMode.None;
	if( Focused == true )
	{
	textFrame.Inflate( -1, 0 );
	ControlPaint.DrawFocusRectangle( pevent.Graphics, textFrame, foreBrush.Color, backBrush.Color );
	}
	}
	pevent.Dispose();
	}
	}
	internal class RadioButtonEx : RadioButton
	{
	private const float factor = 0.6f;
	private const int check = 3;
	public Color DisableFore = SystemColors.GrayText;
	protected override void OnPaint( PaintEventArgs pevent )
	{
	base.OnPaint( pevent );
	// To clear the background, it is necessary to use a non-transparent color and
	// this type of controls usually are, so fetch the first parent's that is not
	var backColor = BackColor;
	while( backColor.A == 0 )
	{
	if( Parent == null )
	{
	break;
	}
	backColor = Parent.BackColor;
	}
	if( backColor.A == 0 )
	{
	// The back color is still transparent, so max the alpha component
	backColor = Color.FromArgb( 255, backColor.R, backColor.G, backColor.B );
	}
	pevent.Graphics.Clear( backColor );
	// Calculate the size of the box by using a large default character (since there could be no text
	// in the control) and neither that ClientRectangle or pevent.ClipRectangle might have a valid value
	var height = TextRenderer.MeasureText( pevent.Graphics, "X", Font ).Height;
	var boxSide = (int)( height * factor );
	var boxFrame = new Rectangle( 0, ( height - boxSide ) / 2, boxSide, boxSide );
	var textFrame = new Rectangle( boxFrame.Right + 2, 0, ClientRectangle.Width - boxFrame.Right - 2, height );
	if( Text.Length == 0 )
	{
	// The box cannot be aligned with non-existing text
	boxFrame.Y = 0;
	}
	// Draw box
	pevent.Graphics.SmoothingMode = SmoothingMode.HighQuality;
	using var backBrush = new SolidBrush( BackColor );
	using var foreBrush = new SolidBrush( ForeColor );
	using var forePen = new Pen( ForeColor );
	if( Enabled == false )
	{
	forePen.Color = foreBrush.Color = DisableFore;
	}
	pevent.Graphics.FillEllipse( backBrush, boxFrame );
	pevent.Graphics.DrawEllipse( forePen, boxFrame );
	if( Checked == true )
	{
	boxFrame.Offset( check, check );
	boxFrame.Width -= check * 2;
	boxFrame.Height -= check * 2;
	pevent.Graphics.FillEllipse( foreBrush, boxFrame );
	}
	// Draw text
	if( Text.Length != 0 )
	{
	using var sf = new StringFormat
	{
	Alignment = StringAlignment.Near,
	LineAlignment = StringAlignment.Center
	};
	TextRenderer.DrawText( pevent.Graphics,
	Text,
	Font,
	textFrame,
	foreBrush.Color,
	TextFormatFlags.Top | TextFormatFlags.Left );
	pevent.Graphics.SmoothingMode = SmoothingMode.None;
	if( Focused == true )
	{
	textFrame.Inflate( -1, 0 );
	ControlPaint.DrawFocusRectangle( pevent.Graphics, textFrame, foreBrush.Color, backBrush.Color );
	}
	}
	pevent.Dispose();
	}
	}

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