Making text width flexible with ttf font

Question

I am inquiring about two things. First I am having an ttf file and it is located in my macair drive. I do not want to add that file into my project structure. How can i import the True_type font from it. I have tried various ways to import it my Java program. e.g. public class TextFixer {
private static String[] names = { "iksswgrg.ttf" }; //this exists on my macair drive and i want to create font from it.

  private static Map<String, Font> cache = new ConcurrentHashMap<String, Font>(names.length);           
  static {                                                                                              
    for (String name : names) {                                                                         
      cache.put(name, getFont(name));                                                                   
    }                                                                                                   
  }                                                                                                     
  public static Font getFont(String name) {                                                             
    Font font = null;                                                                                   
    if (cache != null) {                                                                                
      if ((font = cache.get(name)) != null) {                                                           
        return font;                                                                                    
      }                                                                                                 
    }                                                                                                   
    String fName = "/fonts/" + name;                                                                    
    try {                                                                                               
      InputStream is = TextFixer.class.getResourceAsStream(fName);                                      
      font = new Font("ttf", 0, 16);                                                                    
      //font = Font.createFont(Font.TRUETYPE_FONT, is);                                                 
    } catch (Exception ex) {                                                                            
      ex.printStackTrace();                                                                             
      System.err.println(fName + " not loaded.  Using serif font.");                                    
      font = new Font("serif", Font.PLAIN, 24);                                                         
    }                                                                                                   
    return font;                                                                                        
  }

2nd part is I want to create a String by using Graphics. First I need to have width that is of 130mm. The height of the displayed box will be the tallest character in the provided string. The font size is between 8 and 16. I have an enterprise project which take care of the height and size of the ttf. The problem i face is: I do not want to use swing/javafx libraries. I want to use Graphics library of Java, use Graphics2D to have a rectangle. How can i set its width to be precisely 130mm? Then I want to make that width flexible with according to the Font. I want to draw a string and the string should get adjusted/being flexible in the provided width. I am able to draw a string through g.drawString() but I am unable to see it on console. As I do not want to use Jframe or any Swing/javaFX libraries. I know this seems a bit long but I hope I have explained it well enough. I desperately need help. Please let me know if you guys can help me out here. Thanks in advance

Answer 1

First I am having an ttf file and it is located in my macair drive. I do not want to add that file into my project structure. How can i import the True_type font from it

This is more of a problem to do with "How do you reference a file on the file system" then "How do I load a font", because if you can solve the first, you can solve the second.

File fontFile = new File("some/relative/path/to/your/Font.tff");

or

File fontFile = new File("/some/absolute/path/to/your/Font.tff");

Personally, I like neither, as it it causes too much trouble (working directories, other systems, etc), I prefer to use embedded resources where possible or put the files in a common location.

For example {user.home}/AppData/Local/{application name} on Windows or on Mac you could use {user.home}/Library/Application Support/{application name}, then it doesn't matter where the program is executed from

Loading the font is relatively simple. For my example, I placed the font file in the working directory of the program

System.out.println(new File("Pacifico.ttf").exists());
Font font = Font.createFont(Font.TRUETYPE_FONT, new File("Pacifico.ttf"));

2nd part is I want to create a String by using Graphics. First I need to have width that is of 130mm. The height of the displayed box will be the tallest character in the provided string

This is much more complicated, as images are measured in pixels. In order to know how many pixels make up a given distance, we need to know the DPI of the image.

its 72DPI

Okay then, from that, we can calculate the number of pixels we need

public static double cmToPixel(double cm, double dpi) {
    return (dpi / 2.54) * cm;
}

130mm (13 cm) comes out to be 368.503937007874 @ 72dpi.

From this, we need to find the font point size for a given piece of text to fit within this range.

Now, there are a number of was you can do this, you could simply start at point 1 and perform a linear progression till you pass the range you're after. It's not exactly fast and, as you increase the size, it can become a little error prone.

I've opted for more of a divide and conquer approach

protected static int widthOfText(String text, Font font, float fontSize, Graphics2D g2d) {
    font = font.deriveFont(fontSize);
    FontMetrics fm = g2d.getFontMetrics(font);
    int textWidth = fm.stringWidth(text);
    return textWidth;
}

public static Float pointToFit(double width, String text, Font font, Graphics2D g2d, float min, float max) {
    float fontSize = min + ((max - min) / 2f);
    font = font.deriveFont(fontSize);
    FontMetrics fm = g2d.getFontMetrics(font);
    int textWidth = fm.stringWidth(text);

    if (fontSize == min || fontSize == max) {
        return fontSize;
    }

    if (textWidth < width) {
        return pointToFit(width, text, font, g2d, fontSize, max);
    } else if (textWidth > width) {
        return pointToFit(width, text, font, g2d, min, fontSize);
    }
    return fontSize;
}

Important to note, it's not perfect, but it betters a linear progression :P

With this in hand, we can start calculating the required properties we need...

String text = "Happy, Happy, Joy, Joy";
double width = cmToPixel(13.0, 72.0);

BufferedImage img = new BufferedImage(1, 1, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = img.createGraphics();
float fontSize = pointToFit(width, text, font, g2d, 0, (float)width);

font = font.deriveFont(fontSize);
FontMetrics fm = g2d.getFontMetrics(font);
int height = fm.getHeight();
g2d.dispose();

Okay, so this creates a small (1x1) temporary image. We need Graphics context in order to calculate all the other properties. It then calculates the font point size, from it can then calculate the text height

With all that information in hand, we can get around to actually rendering the text...

img = new BufferedImage((int) Math.round(width), height, BufferedImage.TYPE_INT_ARGB);
g2d = img.createGraphics();
g2d.setFont(font);
fm = g2d.getFontMetrics();
g2d.setColor(Color.BLACK);
g2d.drawString(text, 0, fm.getAscent());
g2d.dispose();

Which will eventually output something like this...

I added the red border before I rendered the text so I could see how well it fitted.

Now, this is a really basic example, what this doesn't do is tell you when the text won't fit (ie, the point size is 1 or 0), you'll have to put traps in to catch that yourself

And, because I know you'll probably have lots of fun putting it together, my test code...

import java.awt.Color;
import java.awt.Font;
import java.awt.FontFormatException;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.GraphicsEnvironment;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.text.NumberFormat;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane;

public class Test {

    public static void main(String[] args) {
        try {
            System.out.println(new File("Pacifico.ttf").exists());
            GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
            Font font = Font.createFont(Font.TRUETYPE_FONT, new File("Pacifico.ttf"));

            String text = "Happy, Happy, Joy, Joy";
            double width = cmToPixel(13.0, 72.0);
            BufferedImage img = new BufferedImage(1, 1, BufferedImage.TYPE_INT_ARGB);
            Graphics2D g2d = img.createGraphics();
            float fontSize = pointToFit(width, text, font, g2d, 0, (float) width);
            System.out.println(width);
            System.out.println(fontSize);
            font = font.deriveFont(fontSize);
            FontMetrics fm = g2d.getFontMetrics(font);
            int height = fm.getHeight();
            g2d.dispose();

            img = new BufferedImage((int) Math.round(width), height, BufferedImage.TYPE_INT_ARGB);
            g2d = img.createGraphics();
            g2d.setColor(Color.RED);
            g2d.drawRect(0, 0, img.getWidth() - 1, img.getHeight() - 1);
            g2d.setFont(font);
            fm = g2d.getFontMetrics();
            g2d.setColor(Color.BLACK);
            g2d.drawString(text, 0, fm.getAscent());
            g2d.dispose();

            JOptionPane.showConfirmDialog(null, new ImageIcon(img));
        } catch (IOException | FontFormatException e) {
            //Handle exception
        }
    }

    public static Float pointToFit(double width, String text, Font font, Graphics2D g2d) {
        return pointToFit(width, text, font, g2d, 0f, Float.MAX_VALUE);
    }

    protected static int widthOfText(String text, Font font, float fontSize, Graphics2D g2d) {
        font = font.deriveFont(fontSize);
        FontMetrics fm = g2d.getFontMetrics(font);
        int textWidth = fm.stringWidth(text);
        return textWidth;
    }

    public static Float pointToFit(double width, String text, Font font, Graphics2D g2d, float min, float max) {
        float fontSize = min + ((max - min) / 2f);
        NumberFormat nf = NumberFormat.getInstance();
        font = font.deriveFont(fontSize);
        FontMetrics fm = g2d.getFontMetrics(font);
        int textWidth = fm.stringWidth(text);

        if (fontSize == min || fontSize == max) {
            return fontSize;
        }

        if (textWidth < width) {
            return pointToFit(width, text, font, g2d, fontSize, max);
        } else if (textWidth > width) {
            return pointToFit(width, text, font, g2d, min, fontSize);
        }
        return fontSize;
    }

    public static double cmToPixel(double cm, double dpi) {
        return (dpi / 2.54) * cm;
    }

}