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C# DrawString with StringFormatFlags: How to Flip Vertical Orientation?

I'm drawing strings on an image and saving it as a TIFF. I need to orient the text like this:
desired output
I'm using this code to create the string format:
formatFlags = (StringFormatFlags.NoClip | StringFormatFlags.DirectionVertical | StringFormatFlags.DirectionRightToLeft);
And this is the output:
actual output
How can I simply flip the orientation around?
Update: Based on the comment, I tried this, but it is place my text way up in the corner instead of where it would be if I didn't add in that sample code. I commented out my original DrawString.
protected virtual void AddTextToBackground(Graphics backgroundGfx, FeatureLocation featureLocation, TextFeature textFeature, int equator) {
Font font = CreateFont(textFeature);
Color fontColor = ColorTranslator.FromHtml(textFeature.FontColor);
Brush textBrush = new SolidBrush(fontColor);
// Determine postion of text box
int xPos = featureLocation.XPos - TEXT_RECT_WIDTH / 2;
int adjustedEquatorOffset = CalculateTextEquatorOffset(featureLocation.EquatorOffset);
//int adjustedEquatorOffset = featureLocation.EquatorOffset;
int yPos = CalculateYPos(equator, adjustedEquatorOffset, TEXT_RECT_WIDTH);
// Rectangle is necessary to create centered text using StringFormat in the DrawString call
Rectangle rect = new Rectangle(xPos, yPos, TEXT_RECT_WIDTH, TEXT_RECT_WIDTH);
// Set up alignment
StringFormat stringFormat = new StringFormat {
Alignment = StringAlignment.Center,
LineAlignment = FindStringAlignment(featureLocation.EquatorOffset)
};
// Determine rotation and set format flags
stringFormat.FormatFlags = GetTextFormatFlags(featureLocation.DefaultRotation, textFeature.Rotation);
// Draw text
SizeF sz = backgroundGfx.VisibleClipBounds.Size;
backgroundGfx.TranslateTransform(sz.Width / 2, sz.Height / 2);
backgroundGfx.RotateTransform(45);
//backgroundGfx.DrawString(textFeature.Text, font, textBrush, rect, stringFormat);
backgroundGfx.DrawString(textFeature.Text, font, textBrush, -(sz.Width/2), -(sz.Height/2), stringFormat);
backgroundGfx.ResetTransform();
}

Issues with DrawString on a Bitmap

I have this constructor that takes in an input of an array of Color objects and some misc strings (like file location and size of list), and stores this heatmap into a bitmap instance called _image_. Everything works out fine, but my main issue is I have no way to render text onto this heatmap. I would like to overlay title text and x and y-axis labels onto this bitmap.
public HeatMap(IEnumerable<Color> colors, int width, int height, string file, int U, int V) {
if (colors == null)
throw new ArgumentNullException("colors");
if (width <= 0)
throw new ArgumentException("width must be at least 1");
if (height <= 0)
throw new ArgumentException("height must be at least 1");
_width = width;
_height = height;
_file = file;
_image = new Bitmap(U, V, PixelFormat.Format32bppArgb);
Graphics graphics = Graphics.FromImage(_image);
graphics.Clear(Color.White);
graphics.Dispose();
int x = 0;
int y = 0;
foreach (Color color in colors) {
_image.SetPixel(x, y, color); // This can be speeded up by using GH_MemoryBitmap if you want.
y++;
if (y >= V) {
y = 0;
x++;
}
if (x >= U)
break;
}
}
Below, I also have a method that resizes the image (without too much distortion), and I figured I might as well make use of this since I have a graphics object I can use, like so:
private Bitmap ResizeBitmap(Bitmap sourceBMP, int width, int height) {
Bitmap result = new Bitmap(width, height);
using (Graphics g = Graphics.FromImage(result)) {
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.NearestNeighbor;
g.DrawImage(sourceBMP, 0, 0, width, height);
g.DrawString("A heatmap.", SystemFonts.DefaultFont, Brushes.Black, 10, 10);
}
return result;
}
Using the above, I was able to overlay text over it, as a starting point. My question is, how do I add a white boarder over the above image (so my text doesn't overlap my graph), and then overlay x and y-axis text onto it?
I guess my specific question really is - how do I render text onto, say, every four columns of my heatmap? In most instances, there are 100 x-axis objects, and like 24 y-axis objects. The y-axis would have the time of the day, while the x-axis has the day of the year. My familiarity with using graphics in C# is very low, so any pointers is very appreciated.

You've to use the DrawString before the graphics.Dispose() and after the Clear().
Graphics graphics = Graphics.FromImage(_image);
graphics.Clear(Color.WhiteSmoke);
graphics.DrawString("your text", SystemFonts.DefaultFont, Brushes.Black, new PointF(0, 0));
graphics.Dispose();
Where the PointF(0, 0) represents the up-left corner of your text placeholder, you've to calculate the text position based on the positions of your heatmap.
UPDATE (alignment)
You can align your text in relation with a virtual rectangle, doing something like:
Graphics graphics = Graphics.FromImage(_image);
graphics.Clear(Color.WhiteSmoke);
StringFormat stringFormat = new StringFormat() { Alignment = StringAlignment.Center, LineAlignment = StringAlignment.Center };
graphics.DrawString("your text", SystemFonts.DefaultFont, Brushes.Black, new RectangleF(0, 0, 100, 100), stringFormat);
graphics.Dispose();
In this case I've created a virtual box of 100x100 positioned on the top-left corner, and the text is h/v centered relatively to this box.

C# adding string to image, using the max font size

I want to add 2 string to an image as follows:
This is Text
------------
------------
------------
--Other-----
How do I use the largest font size possible without have the String go off the side of the image?
example: if text is too big then it goes off the image::
This is Text That is too big
------------
------------
------------
--Other-----

I wrote this script on my previous projects to fit some text into the image by calculating its dimensions for each font-size. when the font size is bigger than the image's width, it lowers the font size by 0.1em and tries again until the text fits in the image. Here's the code :
public static string drawTextOnMarker(string markerfile, string text, string newfilename,Color textColor)
{
//Uri uri = new Uri(markerfile, UriKind.Relative);
//markerfile = uri.AbsolutePath;
//uri = new Uri(newfilename, UriKind.Relative);
//newfilename = uri.AbsolutePath;
if (!System.IO.File.Exists(System.Web.HttpContext.Current.Server.MapPath(newfilename)))
{
try
{
Bitmap bmp = new Bitmap(System.Web.HttpContext.Current.Server.MapPath(markerfile));
Graphics g = Graphics.FromImage(bmp);
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAliasGridFit;
StringFormat strFormat = new StringFormat();
strFormat.Alignment = StringAlignment.Center;
SolidBrush myBrush = new SolidBrush(textColor);
float fontsize = 10;
bool sizeSetupCompleted = false;
while (!sizeSetupCompleted)
{
SizeF mySize = g.MeasureString(text, new Font("Verdana", fontsize, FontStyle.Bold));
if (mySize.Width > 24 || mySize.Height > 13)
{
fontsize-= float.Parse("0.1");
}
else
{
sizeSetupCompleted = true;
}
}
g.DrawString(text, new Font("Verdana", fontsize, FontStyle.Bold), myBrush, new RectangleF(4, 3, 24, 8), strFormat);
bmp.Save(System.Web.HttpContext.Current.Server.MapPath(newfilename));
return newfilename.Substring(2);
}
catch (Exception)
{
return markerfile.Substring(2);
}
}
return newfilename.Substring(2);
}

Here is a quick solution:
using (Graphics g = Graphics.FromImage(bmp))
{
float width = g.MeasureString(text, font).Width;
float scale = bmp.Width / width;
g.ScaleTransform(scale, scale); //Simple trick not to use other Font instance
g.DrawString(text, font, Brushes.Black, PointF.Empty);
g.ResetTransform();
...
}
Your text won't be always 100% width if you use TextRenderingHint.AntiAliasGridFit or similar, but I think that's not a problem as you just want to make sure the text alawys fits in the image.

Calculating the minimum width needed to show text in X lines, in .Net?

How could you calculate the minimum width needed to display a string in X lines, given that text should break on whitespace?

Possible Hint: Perhaps some sort of binary search using Graphics.MeasureString()?

Edit: Didn't realize you wanted to try and fit the text to a fixed number of lines. This was a tough one to try and solve. This is the best I could come up with and may not be the most elegant, but it seems to work:
public SizeF CalculateWidth(Font font, Graphics graphics, int numOfLines,
string text)
{
SizeF sizeFull = graphics.MeasureString(text, font,
new SizeF(
float.PositiveInfinity,
float.PositiveInfinity),
StringFormat.
GenericTypographic);
float width = sizeFull.Width/numOfLines;
float averageWidth = sizeFull.Width/text.Length;
int charsFitted;
int linesFilled;
SizeF needed = graphics.MeasureString(text, font,
new SizeF(width,
float.
PositiveInfinity),
StringFormat.
GenericTypographic,
out charsFitted,
out linesFilled);
while (linesFilled > numOfLines)
{
width += averageWidth;
needed = graphics.MeasureString(text, font,
new SizeF(width,
float.PositiveInfinity),
StringFormat.GenericTypographic,
out charsFitted, out linesFilled);
}
return needed;
}
Example usage:
Font font = new Font("Arial", 12, FontStyle.Regular,
GraphicsUnit.Pixel);
Graphics g = Graphics.FromImage(new Bitmap(1, 1));
string text = "Some random text with words in it.";
SizeF size = CalculateWidth(font, g, 3, text);

Center text output from Graphics.DrawString()

I'm using the .NETCF (Windows Mobile) Graphics class and the DrawString() method to render a single character to the screen.
The problem is that I can't seem to get it centred properly. No matter what I set for the Y coordinate of the location of the string render, it always comes out lower than that and the larger the text size the greater the Y offset.
For example, at text size 12, the offset is about 4, but at 32 the offset is about 10.
I want the character to vertically take up most of the rectangle it's being drawn in and be centred horizontally. Here's my basic code. this is referencing the user control it's being drawn in.
Graphics g = this.CreateGraphics();
float padx = ((float)this.Size.Width) * (0.05F);
float pady = ((float)this.Size.Height) * (0.05F);
float width = ((float)this.Size.Width) - 2 * padx;
float height = ((float)this.Size.Height) - 2 * pady;
float emSize = height;
g.DrawString(letter, new Font(FontFamily.GenericSansSerif, emSize, FontStyle.Regular),
new SolidBrush(Color.Black), padx, pady);
Yes, I know there is the label control that I could use instead and set the centring with that, but I actually do need to do this manually with the Graphics class.

I'd like to add another vote for the StringFormat object.
You can use this simply to specify "center, center" and the text will be drawn centrally in the rectangle or points provided:
StringFormat format = new StringFormat();
format.LineAlignment = StringAlignment.Center;
format.Alignment = StringAlignment.Center;
However there is one issue with this in CF. If you use Center for both values then it turns TextWrapping off. No idea why this happens, it appears to be a bug with the CF.

To align a text use the following:
StringFormat sf = new StringFormat();
sf.LineAlignment = StringAlignment.Center;
sf.Alignment = StringAlignment.Center;
e.Graphics.DrawString("My String", this.Font, Brushes.Black, ClientRectangle, sf);
Please note that the text here is aligned in the given bounds. In this sample this is the ClientRectangle.

Through a combination of the suggestions I got, I came up with this:
private void DrawLetter()
{
Graphics g = this.CreateGraphics();
float width = ((float)this.ClientRectangle.Width);
float height = ((float)this.ClientRectangle.Width);
float emSize = height;
Font font = new Font(FontFamily.GenericSansSerif, emSize, FontStyle.Regular);
font = FindBestFitFont(g, letter.ToString(), font, this.ClientRectangle.Size);
SizeF size = g.MeasureString(letter.ToString(), font);
g.DrawString(letter, font, new SolidBrush(Color.Black), (width-size.Width)/2, 0);
}
private Font FindBestFitFont(Graphics g, String text, Font font, Size proposedSize)
{
// Compute actual size, shrink if needed
while (true)
{
SizeF size = g.MeasureString(text, font);
// It fits, back out
if (size.Height <= proposedSize.Height &&
size.Width <= proposedSize.Width) { return font; }
// Try a smaller font (90% of old size)
Font oldFont = font;
font = new Font(font.Name, (float)(font.Size * .9), font.Style);
oldFont.Dispose();
}
}
So far, this works flawlessly.
The only thing I would change is to move the FindBestFitFont() call to the OnResize() event so that I'm not calling it every time I draw a letter. It only needs to be called when the control size changes. I just included it in the function for completeness.

To draw a centered text:
TextRenderer.DrawText(g, "my text", Font, Bounds, ForeColor, BackColor,
TextFormatFlags.HorizontalCenter |
TextFormatFlags.VerticalCenter |
TextFormatFlags.GlyphOverhangPadding);
Determining optimal font size to fill an area is a bit more difficult. One working soultion I found is trial-and-error: start with a big font, then repeatedly measure the string and shrink the font until it fits.
Font FindBestFitFont(Graphics g, String text, Font font,
Size proposedSize, TextFormatFlags flags)
{
// Compute actual size, shrink if needed
while (true)
{
Size size = TextRenderer.MeasureText(g, text, font, proposedSize, flags);
// It fits, back out
if ( size.Height <= proposedSize.Height &&
size.Width <= proposedSize.Width) { return font; }
// Try a smaller font (90% of old size)
Font oldFont = font;
font = new Font(font.FontFamily, (float)(font.Size * .9));
oldFont.Dispose();
}
}
You'd use this as:
Font bestFitFont = FindBestFitFont(g, text, someBigFont, sizeToFitIn, flags);
// Then do your drawing using the bestFitFont
// Don't forget to dispose the font (if/when needed)

Here's some code. This assumes you are doing this on a form, or a UserControl.
Graphics g = this.CreateGraphics();
SizeF size = g.MeasureString("string to measure");
int nLeft = Convert.ToInt32((this.ClientRectangle.Width / 2) - (size.Width / 2));
int nTop = Convert.ToInt32((this.ClientRectangle.Height / 2) - (size.Height / 2));
From your post, it sounds like the ClientRectangle part (as in, you're not using it) is what's giving you difficulty.

You can use an instance of the StringFormat object passed into the DrawString method to center the text.
See Graphics.DrawString Method and StringFormat Class.