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java - String to BufferedImage with set borders and new line

I am new to StackOverflow and need help with following problem.

background:

I have to do a project for school where we get a lego mindstorm robot that prints stuff (coordinate based). My idea was to implement program in Java that translates (Google translation API) a given input, uses that String to create a BufferedImage and then reads out the coordinates of that image, so the robot can draw/print the translated input. I got everything to work except the writing of the text on to the BufferedImage.

problem:

I'm looking for a way to create a BufferedImage using a input String. The image should have fixed borders (160x200 px since that is the size of the robots coordinate system). I managed to create a BufferedImage with said borders, but when I insert the String on the image, it just leaves the image, so the back part of the String gets lost. Is it possible to create a new line in the BufferedImage automatically, when it reaches the border?

I am only worrying about the width right now, so its not a problem, if it gets cut off at the bottom (although if you know how to change that you can tell me also). Font should be:

Font font = new Font("Arial", Font.PLAIN, 25);

because it supports the languages I use.

Thank you for your help!

TL;DR: BufferedImage with fixed size and String as content. String shouldn't get cut off: new line, if string reaches the border, without words getting cut off.


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1 Answer

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Well since I was told to post my answer (even though that keeps future people from doing their assignments on their own), here it is. This class creates a BufferedImage (160x200 px) from a given input String (also saves the image as a file in the source folder). I'm sure it still can be improved, but I wouldn't know how, since thats all that I managed to make from the help that I got on here.

example output of an image


import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.font.FontRenderContext;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;

import javax.imageio.ImageIO;

public class TextToImage {
    
    public static BufferedImage createImage(String inputString) throws IOException{
        
        BufferedImage image = createGraphics(inputString);
        saveImage(image);
        
        return image;
    }
    
    public static BufferedImage createGraphics(String inputString) {
        
        BufferedImage bufferedImage = new BufferedImage(160, 195, BufferedImage.TYPE_INT_RGB);
        Font font = new Font("Arial", Font.PLAIN, 25);
        Graphics2D graphics2D = prepareGraphics(bufferedImage);
        double baseY = getY(getBounds(font, inputString, graphics2D));
        
        if(isLatin(inputString)) {
            drawLinesAsWords(graphics2D, inputString, font, baseY);
        } else {
            drawLinesAsCharacters(graphics2D, inputString, font, baseY);
        }
        
        graphics2D.dispose();

        return bufferedImage;
    }
    
    public static double getY(Rectangle2D bounds) {
        
        double ascent = - bounds.getY();
        double baseY = 0 + ascent;
        return baseY;
    }
    
    public static Rectangle2D getBounds(Font font, String content, Graphics2D graphics2D) {
        FontRenderContext context = graphics2D.getFontRenderContext();
        Rectangle2D bounds = font.getStringBounds(content, context);
        
        return bounds;
    }
    
    public static Graphics2D prepareGraphics(BufferedImage bufferedImage) {
        Graphics2D graphics2D = (Graphics2D)bufferedImage.getGraphics();
        graphics2D.setBackground(Color.GRAY);
        graphics2D.clearRect(0, 0, 160, 195);
        graphics2D.setPaint(Color.BLACK);
        
        return graphics2D;
    }
    
    public static boolean isLatin(String inputString) {
        String regex = "^.*\p{IsLatin}.*";
        boolean result = inputString.matches(regex);
        if(result) {
            return true;
        } else {
            return false;
        }
    }
    
    public static void saveImage(BufferedImage bufferedImage) throws IOException {
        
        ImageIO.write(bufferedImage, "png", new File("./Image.jpeg"));
    }
    
    public static int getHeight(Font font, Graphics2D g) {
        
        int lineHeight = g.getFontMetrics(font).getHeight();
        return lineHeight;
    }

    public static void drawLinesAsWords(Graphics2D graphics2D, String content, Font font, double baseY) {
        
        int lineHeight = getHeight(font, graphics2D);
        int leftBorder = 5;
        String[] wordArray = content.split(" ");
        FontMetrics fontMetrics = graphics2D.getFontMetrics(font);
        String currentContent = "";
        double leftTopCornerLine = baseY;
        
        for(int i = 0; i < wordArray.length; i++) {
            
            if(leftTopCornerLine < 195) {

                if(fontMetrics.stringWidth(currentContent)>=240) {
                    if(fontMetrics.stringWidth(wordArray[i])<=240-fontMetrics.stringWidth(currentContent)) {
                        currentContent += " " + wordArray[i];
                        graphics2D.drawString(currentContent, leftBorder, (int)leftTopCornerLine);
                        currentContent ="";
                        leftTopCornerLine += lineHeight;
                    } else {
                        graphics2D.drawString(currentContent, leftBorder, (int)leftTopCornerLine);
                        currentContent ="";
                        leftTopCornerLine += lineHeight;
                    }
                } else {
                    int contentWidth = fontMetrics.stringWidth(currentContent);
                    if(contentWidth<=260) {
                        currentContent += " " + wordArray[i];
                    }
                }
            } else {
                System.out.println("Input was cut, because it was too long.");
                break;
            }
        }
    }
    
    public static void drawLinesAsCharacters(Graphics2D graphics2D, String content, Font font, double baseY) {
        int lineHeight = getHeight(font, graphics2D);
        int leftBorder = 5;
        String[] characterArray = content.split("");
        FontMetrics fontMetrics = graphics2D.getFontMetrics(font);
        String currentContent = "";
        double leftTopCornerLine = baseY;
        
        for(int i = 0; i < characterArray.length; i++) {
            
            if(leftTopCornerLine < 195) {

                if(fontMetrics.stringWidth(currentContent)>=210) {
                    if(fontMetrics.stringWidth(characterArray[i])<=210-fontMetrics.stringWidth(currentContent)) {
                        currentContent += characterArray[i];
                        graphics2D.drawString(currentContent, leftBorder, (int)leftTopCornerLine);
                        currentContent ="";
                        leftTopCornerLine += lineHeight;
                    } else {
                        graphics2D.drawString(currentContent, leftBorder, (int)leftTopCornerLine);
                        currentContent ="";
                        leftTopCornerLine += lineHeight;
                    }
                } else {
                    int contentWidth = fontMetrics.stringWidth(currentContent);
                    if(contentWidth<=230) {
                        currentContent += characterArray[i];
                    }
                }
            } else {
                System.out.println("Input was cut, because it was too long.");
                break;
            }
        }
    }
    
}


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