I need to generate a single image, with a single character (letter) in it, which completely fills the image. I found a Bitmap.MeasureString option.
So what I tried to do was measure the size the string would be using this function, and then resizing the image to match, and then draw the letter.
But I am getting loads of white space all around the letter. I need the border of the image to be on the edges of the letter.
So a W would be a wide image, but an I would be a very narrow image.
I drew a line from the top left to bottom right to show what's happening.
Can you spot an issue with my code? Am I maybe misunderstanding this function? Or, it doesn't work as I'd hoped?
In the example image I posted, I want the top border of the image to be on the top border of the A. And the left border touching the bottom right hand of the A. And the bottom being right on the bottom edge of the A.
Here's what I am trying:
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
namespace SpikeFontToImage
{
class Program
{
static void Main(string[] args)
{
Bitmap source = new Bitmap(1, 1);
Bitmap destination;
Font stringFont = new Font("Tohoma", 1024);
string text = "A";
using (var measure = Graphics.FromImage(source))
{
var size = measure.MeasureString(text, stringFont);
Console.WriteLine($"{text} is {size} in size");
destination = new Bitmap( (int)size.Width, (int)size.Height);
RectangleF rectf = new RectangleF(0, 0, destination.Width, destination.Height);
StringFormat format = new StringFormat()
{
Alignment = StringAlignment.Center,
LineAlignment = StringAlignment.Center
};
//RectangleF rectf = new RectangleF(70, 90, 90, 50);
Graphics g = Graphics.FromImage(destination);
g.SmoothingMode = SmoothingMode.AntiAlias;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.PixelOffsetMode = PixelOffsetMode.HighQuality;
g.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;
g.DrawString(text, stringFont, Brushes.Black, rectf, format);
Pen pen = new Pen(Color.GreenYellow, 3);
g.DrawLine(pen, new Point(0, 0), new Point((int)size.Width, (int)size.Height));
g.Flush();
destination.Save(#"c:\temp\ccl.jpg");
}
}
}
}
I want to create a default avatar image which is a circle with initials in it. I want to do this on the server side as a png. Is this possible using the .net graphics library?
I ended up doing this. Thanks for pointing me in the right direction TaW
public ActionResult Avatar()
{
using (var bitmap = new Bitmap(50, 50))
{
using (Graphics g = Graphics.FromImage(bitmap))
{
g.Clear(Color.White);
using (Brush b = new SolidBrush(ColorTranslator.FromHtml("#eeeeee")))
{
g.FillEllipse(b, 0, 0, 49, 49);
}
float emSize = 12;
g.DrawString("AM", new Font(FontFamily.GenericSansSerif, emSize, FontStyle.Regular),
new SolidBrush(Color.Black), 10, 15);
}
using (var memStream = new System.IO.MemoryStream())
{
bitmap.Save(memStream, System.Drawing.Imaging.ImageFormat.Png);
var result = this.File(memStream.GetBuffer(), "image/png");
return result;
}
}
}
I want to create a Picturebox that adapts its shape to a string of a certain Font. I need this so that I can later create texts and lay it over an AxWindowsMediaPlayer control.
Therefore I created the following class:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Drawing;
namespace myProject
{
class ShapedPictureBoxes : PictureBox
{
public ShapedPictureBoxes()
{
this.Paint += this.shapedPaint;
}
void shapedPaint(object sender, PaintEventArgs e)
{
System.Drawing.Drawing2D.GraphicsPath graphicsPath = new System.Drawing.Drawing2D.GraphicsPath();
Font font = new Font("Arial", 14f);
float emSize = e.Graphics.DpiY*font.Size/72;
graphicsPath.AddString(text, new FontFamily("Arial"), (int)System.Drawing.FontStyle.Regular, emSize, new Point(0,0), new StringFormat());
e.Graphics.DrawString(text, font, Brushes.Red, new Point(0, 0));
this.Region = new Region(graphicsPath);
}
public string text = "Here comes the sun, doo da doo do";
}
}
The problem now is, that the "Graphics.DrawString" does not match the graphicspath.AddString, probably because FontFamily isn't the same as Font. How can I match them?
So: How can I convert Fontfamily to Font or viceversa?
This is how it looks like:
You need to account for the fact that the Font size is specified in units of points, but the AddString() size is specified in device units.
You can convert the units as follows:
Font font = new Font("Arial", 14f, FontStyle.Bold);
float emSize = e.Graphics.DpiY * font.Size / 72; // Here's the conversion.
graphicsPath.AddString(text, new FontFamily("Arial"), (int)System.Drawing.FontStyle.Bold, emSize, new Point(0, 0), new StringFormat());
Note that I'm passing the calculated emSize to AddString() instead of passing 14f.
How can I create in .NET 4.5 / C# a font with a adaptive size to fit a specified rectangle ?
I have a resize based on the string length, the longer the string, the smaller the fontsize, but it does not work very well, if the string is too long the text gets very small. The problem with this method is that if I change the rectangle size all the font sizes are not good again.
It's been a while but I came across this issue.
MSDN offers a sample with a GetAdjustedFont method to help with this process:
(shamelessly stolen from https://msdn.microsoft.com/en-us/library/bb986765.aspx)
public Font GetAdjustedFont(Graphics g, string graphicString, Font originalFont, int containerWidth, int maxFontSize, int minFontSize, bool smallestOnFail)
{
Font testFont = null;
// We utilize MeasureString which we get via a control instance
for (int adjustedSize = maxFontSize; adjustedSize >= minFontSize; adjustedSize--)
{
testFont = new Font(originalFont.Name, adjustedSize, originalFont.Style);
// Test the string with the new size
SizeF adjustedSizeNew = g.MeasureString(graphicString, testFont);
if (containerWidth > Convert.ToInt32(adjustedSizeNew.Width))
{
// Good font, return it
return testFont;
}
}
// If you get here there was no fontsize that worked
// return minimumSize or original?
if (smallestOnFail)
{
return testFont;
}
else
{
return originalFont;
}
}
With Graphics.MeasureString you can measure the size of a string, so you can calculate what you need.
Sample from MSDN
private void MeasureStringMin(PaintEventArgs e)
{
// Set up string.
string measureString = "Measure String";
Font stringFont = new Font("Arial", 16);
// Measure string.
SizeF stringSize = new SizeF();
stringSize = e.Graphics.MeasureString(measureString, stringFont);
// Draw rectangle representing size of string.
e.Graphics.DrawRectangle(new Pen(Color.Red, 1), 0.0F, 0.0F, stringSize.Width, stringSize.Height);
// Draw string to screen.
e.Graphics.DrawString(measureString, stringFont, Brushes.Black, new PointF(0, 0));
}
You can measure the string width with whatever font size (e.g. 16), and then you can calculate your desired font size like this:
fontSize = (previouslyMeasuredFontSize * targetWidthOfString) / previouslyMeasuredStringWidth;
I also needed something similar. I created some code to answer the need of drawing text inside a defined rectangle with several auto font size options (see DrawMethod enum). It also supports auto warp with and without auto font size. My solution was inspired by the answers above.
Be sure to add WindowsBase and PresentationCore assemblies.
DrawTextToBitmap.cs
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ReportPrepare
{
class TextDrawing
{
public enum DrawMethod
{
AutosizeAccordingToText, // create the smallest bitmap needed to draw the text without word warp
AutoFitInConstantRectangleWithoutWarp, // draw text with the biggest font possible while not exceeding rectangle dimensions, without word warp
AutoWarpInConstantRectangle, // draw text in rectangle while performing word warp. font size is a constant input. drawing may exceed bitmap rectangle.
AutoFitInConstantRectangleWithWarp // draw text with the biggest font possible while not exceeding rectangle dimensions, with word warp
}
private static void SetGraphicsHighQualityForTextRendering(Graphics g)
{
// The smoothing mode specifies whether lines, curves, and the edges of filled areas use smoothing (also called antialiasing). One exception is that path gradient brushes do not obey the smoothing mode. Areas filled using a PathGradientBrush are rendered the same way (aliased) regardless of the SmoothingMode property.
g.SmoothingMode = SmoothingMode.AntiAlias;
// The interpolation mode determines how intermediate values between two endpoints are calculated.
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
// Use this property to specify either higher quality, slower rendering, or lower quality, faster rendering of the contents of this Graphics object.
g.PixelOffsetMode = PixelOffsetMode.HighQuality;
// This one is important
g.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;
}
public static Size MeasureDrawTextBitmapSize(string text, Font font)
{
Bitmap bmp = new Bitmap(1, 1);
using (Graphics g = Graphics.FromImage(bmp))
{
SizeF size = g.MeasureString(text, font);
return new Size((int)(Math.Ceiling(size.Width)), (int)(Math.Ceiling(size.Height)));
}
}
public static int GetMaximumFontSizeFitInRectangle(string text, Font font, RectangleF rectanglef, bool isWarp, int MinumumFontSize=6, int MaximumFontSize=1000)
{
Font newFont;
Rectangle rect = Rectangle.Ceiling(rectanglef);
for (int newFontSize = MinumumFontSize; ; newFontSize++)
{
newFont = new Font(font.FontFamily, newFontSize, font.Style);
List<string> ls = WarpText(text, newFont, rect.Width);
StringBuilder sb = new StringBuilder();
if (isWarp)
{
for (int i = 0; i < ls.Count; ++i)
{
sb.Append(ls[i] + Environment.NewLine);
}
}
else
{
sb.Append(text);
}
Size size = MeasureDrawTextBitmapSize(sb.ToString(), newFont);
if (size.Width > rectanglef.Width || size.Height > rectanglef.Height)
{
return (newFontSize - 1);
}
if (newFontSize >= MaximumFontSize)
{
return (newFontSize - 1);
}
}
}
public static List<string> WarpText(string text, Font font, int lineWidthInPixels)
{
string[] originalLines = text.Split(new string[] { " " }, StringSplitOptions.None);
List<string> wrappedLines = new List<string>();
StringBuilder actualLine = new StringBuilder();
double actualWidthInPixels = 0;
foreach (string str in originalLines)
{
Size size = MeasureDrawTextBitmapSize(str, font);
actualLine.Append(str + " ");
actualWidthInPixels += size.Width;
if (actualWidthInPixels > lineWidthInPixels)
{
actualLine = actualLine.Remove(actualLine.ToString().Length - str.Length - 1, str.Length);
wrappedLines.Add(actualLine.ToString());
actualLine.Clear();
actualLine.Append(str + " ");
actualWidthInPixels = size.Width;
}
}
if (actualLine.Length > 0)
{
wrappedLines.Add(actualLine.ToString());
}
return wrappedLines;
}
public static Bitmap DrawTextToBitmap(string text, Font font, Color color, DrawMethod mode, RectangleF rectanglef)
{
StringFormat drawFormat = new StringFormat();
Bitmap bmp;
switch (mode)
{
case DrawMethod.AutosizeAccordingToText:
{
Size size = MeasureDrawTextBitmapSize(text, font);
if (size.Width == 0 || size.Height == 0)
{
bmp = new Bitmap(1, 1);
}
else
{
bmp = new Bitmap(size.Width, size.Height);
}
using (Graphics g = Graphics.FromImage(bmp))
{
SetGraphicsHighQualityForTextRendering(g);
g.DrawString(text, font, new SolidBrush(color), 0, 0);
return bmp;
}
}
case DrawMethod.AutoWarpInConstantRectangle:
{
Rectangle rect = Rectangle.Ceiling(rectanglef);
bmp = new Bitmap(rect.Width,rect.Height);
if (rect.Width == 0 || rect.Height == 0)
{
bmp = new Bitmap(1, 1);
}
else
{
bmp = new Bitmap(rect.Width, rect.Height);
}
using (Graphics g = Graphics.FromImage(bmp))
{
SetGraphicsHighQualityForTextRendering(g);
g.DrawString(text, font, new SolidBrush(color), rectanglef, drawFormat);
return bmp;
}
}
case DrawMethod.AutoFitInConstantRectangleWithoutWarp:
{
Rectangle rect = Rectangle.Ceiling(rectanglef);
bmp = new Bitmap(rect.Width, rect.Height);
if (rect.Width == 0 || rect.Height == 0)
{
bmp = new Bitmap(1, 1);
}
else
{
bmp = new Bitmap(rect.Width, rect.Height);
}
using (Graphics g = Graphics.FromImage(bmp))
{
int fontSize = GetMaximumFontSizeFitInRectangle(text, font, rectanglef, false);
SetGraphicsHighQualityForTextRendering(g);
g.DrawString(text, new Font(font.FontFamily, fontSize,font.Style, GraphicsUnit.Point), new SolidBrush(color), rectanglef, drawFormat);
return bmp;
}
}
case DrawMethod.AutoFitInConstantRectangleWithWarp:
{
Rectangle rect = Rectangle.Ceiling(rectanglef);
if (rect.Width == 0 || rect.Height == 0)
{
bmp = new Bitmap(1, 1);
}
else
{
bmp = new Bitmap(rect.Width, rect.Height);
}
using (Graphics g = Graphics.FromImage(bmp))
{
int fontSize = GetMaximumFontSizeFitInRectangle(text, font, rectanglef, true);
SetGraphicsHighQualityForTextRendering(g);
g.DrawString(text, new Font(font.FontFamily, fontSize, font.Style, GraphicsUnit.Point), new SolidBrush(color), rectanglef, drawFormat);
return bmp;
}
}
}
return null;
}
}
}
Usage Example:
Form1.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
// add WindowsBase and PresentationCore assemblies
namespace ReportPrepare
{
public partial class Form1 : Form
{
PictureBox picbox = new PictureBox();
int i = 0;
Timer t = new Timer();
public Form1()
{
InitializeComponent();
this.Controls.Add(picbox);
picbox.Dock = DockStyle.Fill;
t.Interval = 5000;
t.Tick += t_Tick;
t.Enabled = true;
this.Shown += Form1_Shown;
this.SizeChanged += Form1_SizeChanged;
this.Size = new Size(812, 400);
this.StartPosition = FormStartPosition.CenterScreen;
}
void Form1_Shown(object sender, EventArgs e)
{
DrawText();
}
void t_Tick(object sender, EventArgs e)
{
i++;
if (i > 3)
{
i = 0;
}
DrawText();
}
private void DrawText()
{
// text and font
string text = "one two three four five six seven eight nine ten eleven twelve";
Font font = new System.Drawing.Font("Arial", 30, FontStyle.Regular, GraphicsUnit.Point);
switch (i)
{
case 0:
picbox.Image = TextDrawing.DrawTextToBitmap(text, font, Color.Red, TextDrawing.DrawMethod.AutosizeAccordingToText, new RectangleF(0, 0, picbox.Width, picbox.Height));
break;
case 1:
picbox.Image = TextDrawing.DrawTextToBitmap(text, font, Color.Red, TextDrawing.DrawMethod.AutoFitInConstantRectangleWithoutWarp, new RectangleF(0, 0, picbox.Width, picbox.Height));
break;
case 2:
picbox.Image = TextDrawing.DrawTextToBitmap(text, font, Color.Red, TextDrawing.DrawMethod.AutoWarpInConstantRectangle, new RectangleF(0, 0, picbox.Width, picbox.Height));
break;
case 3:
picbox.Image = TextDrawing.DrawTextToBitmap(text, font, Color.Red, TextDrawing.DrawMethod.AutoFitInConstantRectangleWithWarp, new RectangleF(0, 0, picbox.Width, picbox.Height));
break;
}
this.Text = ((TextDrawing.DrawMethod)(i)).ToString() + " Please resize window size by mouse to see drawing methods differences";
}
private void Form1_SizeChanged(object sender, EventArgs e)
{
t.Enabled = false;
t.Enabled = true;
DrawText();
}
}
}
The example toggles between drawing modes automatically once every 5 seconds. The picturebox is docked inside main form. Resizing of the form shows the user the difference between the drawing modes.
here is the code i'm using, i really need to make it so the text does not appear inside of a box. is that possible?
int width = (int)g.MeasureString(line, f).Width;
int height = (int)g.MeasureString(line,f).Height;
b = new Bitmap(b, new Size(width, height));
g = Graphics.FromImage(b);
g.Clear(Color.Empty);
g.DrawString(line,f, new SolidBrush(Color.Black), 0, 0);
b.Save(savepoint+line+".tif", System.Drawing.Imaging.ImageFormat.Tiff);
g.Flush();
What i mean is there can be no Rectangle around the text that is converted to image. So I need to watch it to the same color to create the illusion there is no box, or to never write out that rectangle period.
Use the color Transparent for the backgtround and a file format that supports transparency, like PNG:
var measure = g.MeasureString(line, f);
int width = (int)measure.Width;
int height = (int)measure.Height;
using (Bitmap b = new Bitmap(width, height)) {
using (Graphics bg = Graphics.FromImage(b)) {
bg.Clear(Color.Transparent);
using (Brush black = new SolidBrush(Color.Black)) {
bg.DrawString(line, f, black, 0, 0);
}
}
b.Save(savepoint+line+".png", System.Drawing.Imaging.ImageFormat.Png);
}
I notice that you did overwrite your Graphics instance, didn't dispose the objects that you create, and called Graphics.Flush for no apparent reason...