How to drop shadow on text in winform. Especially, draw text on a bitmap object. I know we can draw that text with a dark color and bring to the right position to make it like a shadow. But this shadow seems so slim and solid. I want it wider and blurred. I found some functions that can blur and image. But when I apply to my situation, it turns the transparent area to black. Please give me a guide.
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As an alternative to rendering a blurred shadow, a more performance-friendly option might be to render the shadow slightly offset down and to the right (as you initially suggested), but with an alpha-transparency so that the shadow does not appear to be so "solid":
protected void RenderDropshadowText(
Graphics graphics, string text, Font font, Color foreground, Color shadow,
int shadowAlpha, PointF location)
{
const int DISTANCE = 2;
for (int offset = 1; 0 <= offset; offset--)
{
Color color = ((offset < 1) ?
foreground : Color.FromArgb(shadowAlpha, shadow));
using (var brush = new SolidBrush(color))
{
var point = new PointF()
{
X = location.X + (offset * DISTANCE),
Y = location.Y + (offset * DISTANCE)
};
graphics.DrawString(text, font, brush, point);
}
}
}
To give an example of how this would be called from code, such as in an OnPaint method:
RenderDropshadowText(e.Graphics, "Dropshadow Text",
this.Font, Color.MidnightBlue, Color.DimGray, 64, new PointF(10, 10));
To spruce things up a bit, and get a more convincing shadow effect, we might be able to modify the above function to simulate a blur effect by drawing the text with further alpha transparency slightly, once to the left, and once slightly to the right of the drop shadow:
if (offset > 0)
{
using (var blurBrush = new SolidBrush(Color.FromArgb((shadowAlpha / 2), color)))
{
graphics.DrawString(text, font, blurBrush, (point.X + 1), point.Y);
graphics.DrawString(text, font, blurBrush, (point.X - 1), point.Y);
}
}
Here is a screenshot of the resultant output:
Lemonseed
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1
You can try to use Path (if you can produce a path out of a text?) and PathGradientBrush
using (PathGradientBrush brush = new PathGradientBrush(pathShadow))
{
ColorBlend blend = new ColorBlend();
blend.Colors = new Color[] { Color.Transparent, Color.Black };
blend.Positions = new float[] { 0.0f, 1.0f };
brush.InterpolationColors = blend;
graph.FillPath(brush, pathShadow);
}
Or you can try to do something with the overlay image (it's just an idea, here is an example of making something glowing defined by path):
// inside OnPaint
// overlay
using (Bitmap bmp = new Bitmap(Width, Height, PixelFormat.Format32bppArgb))
{
using (Graphics gtemp = Graphics.FromImage(bmp))
{
// fake glowing
using (LinearGradientBrush brush = new LinearGradientBrush(ClientRectangle, Color.FromArgb(200, 255, 255, 255), Color.FromArgb(0, 0, 0, 0), LinearGradientMode.Vertical))
{
brush.SetBlendTriangularShape(0.5f, 1.0f);
gtemp.FillPath(brush, path);
}
// draw on screen
e.Graphics.DrawImage(bmp, 0, 0);
}
}
Sinatr
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0
Here's a very simplified implementation of a WinForms Label Control that creates shadows:
using System;
using System.Drawing;
using System.Windows.Forms;
namespace MyCustom.Controls
{
public class ShadowLabel : Label
{
#region Properties
protected int _xOffset = 5;
protected int _yOffset = 5;
#endregion
#region Constructor
public ShadowLabel() : base() => InitializeComponent();
#endregion
#region Accessors
/// <summary>Specifies the solid-colour value of the shadow. No alpha information from this setting is used.</summary>
/// <remarks>Alpha blending is handled programmatically via the <i>Alpha</i> accessor value.</remarks>
/// <seealso cref="Alpha"/>
public Color ShadowColor { get; set; } = Color.Black;
/// <summary>Specifies the vertical translation of the shadow (up/down). Range: -25 to +25.</summary>
/// <remarks>Using a negative value shifts the shadow up, while a positive value shifts downwards.</remarks>
public int xOffset
{
get => this._xOffset;
set => this._xOffset = (value < 0) ? Math.Max(value,-25) : Math.Min( 25, value );
}
/// <summary>Specifies the horizontal translation of the shadow (left/right). Range: -25 to +25.</summary>
/// <remarks>Using a negative value shifts the shadow left, while a positive value goes right.</remarks>
public int yOffset
{
get => this._yOffset;
set => this._yOffset = (value < 0) ? Math.Max( value, -25 ) : Math.Min( 25, value );
}
/// <summary>Specifies the starting Alpha value of the shadow (how solid is it).</summary>
/// <remarks>The shadow is made more transparent as it deepens, from this value to zero.</remarks>
public byte Alpha { get; set; } = 255;
#endregion
#region Methods
protected override void OnPaint( PaintEventArgs e )
{
Graphics g = e.Graphics;
int xStart = Math.Min( this.Location.X, this.Location.X + xOffset ),
xEnd = Math.Max( this.Location.X, this.Location.X + xOffset ),
yStart = Math.Min( this.Location.Y, this.Location.Y + yOffset ),
yEnd = Math.Max( this.Location.Y, this.Location.Y + yOffset ),
steps, xIncrement, yIncrement, alphaIncrement;
steps = Math.Max( xEnd - xStart, yEnd - yStart );
xIncrement = ( xOffset < 0 ? -1 : 1 ) * (int)Math.Floor( (xEnd - xStart) / (float)steps );
yIncrement = ( yOffset < 0 ? -1 : 1 ) * (int)Math.Floor( (yEnd - yStart) / (float)steps );
alphaIncrement = (int)Math.Floor( Alpha / (float)steps );
if ( steps > 0 )
{
for ( int i = steps; i > 0; i-- )
g.DrawString(
this.Text,
this.Font,
new SolidBrush(
Color.FromArgb(
this.Alpha - (alphaIncrement * i),
ShadowColor.R,
ShadowColor.G,
ShadowColor.B
)
),
new PointF()
{
X = (xIncrement * i), // this.Location.X + (xIncrement * i),
Y = (yIncrement * i) // this.Location.Y + (yIncrement * i)
}
);
g.DrawString( this.Text, this.Font, new SolidBrush( this.ForeColor ), new PointF( 0f, 0f ) );
}
else base.OnPaint( e );
}
#endregion
/// <summary>Required designer variable.</summary>
private System.ComponentModel.IContainer components = null;
/// <summary>Clean up any resources being used.</summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose( bool disposing )
{
if ( disposing && (components != null) )
components.Dispose();
base.Dispose( disposing );
}
#region Component Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent() =>
components = new System.ComponentModel.Container();
#endregion
}
}
NetXpert
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-1
I know that answer may not behelpful at all but if its just static text use an image instead