Java Graphics2D 缩放字体以填充背景

Question

我在缩放字体以适应背景宽度时遇到问题。我有一个 1000 高度和 350 宽度的背景，并且当字体大于背景时我尝试缩放字体。我用不同的字体做了几次测试，结果是相同的，一些字母丢失或文本末尾有空格。

这是代码:

 import java.awt.Color;
 import java.awt.Font;
 import java.awt.FontMetrics;
 import java.awt.Graphics2D;
 import java.awt.RenderingHints;
 import java.awt.geom.AffineTransform;
 import java.awt.image.BufferedImage;
 import java.io.File;
 import java.io.IOException;
 import javax.imageio.ImageIO;

public class PruebaStackoverflow {

 public static void main(String[] args) {

    String titleText = null;
    Graphics2D g2D = null;
    Font testFont = null;

    File imageGrayBackgroundFile = new File(
            "resources/pruebaAltaResolucionGris.png");
    File destinationImageGray = new File("resources/outputTextGray.png");

    BufferedImage background = readImage(imageGrayBackgroundFile);

    titleText = "Lorem ipsum dolor sit amet asdkf sdm";
    testFont = new Font("Lucida Console", Font.PLAIN, 50);

    g2D = background.createGraphics();
    g2D.setColor(Color.BLACK);
    g2D.setFont(testFont);

    g2D.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
            RenderingHints.VALUE_TEXT_ANTIALIAS_ON);

    g2D = scaleFontFromFontMetrics(g2D, background, titleText);

    g2D.drawString(titleText, 0, 150);
    g2D.dispose();

    writeImage(destinationImageGray, background);

}

private static Graphics2D scaleFontFromFontMetrics(Graphics2D g2D,
        BufferedImage backgroundImage, String text) {
    double xScale;
    double yScale;
    double scale;
    Integer backgroundWidth = null;
    Integer backgroundHeight = null;
    Integer textWidth = null;
    Integer textHeigth = null;

    backgroundWidth = backgroundImage.getWidth();
    backgroundHeight = backgroundImage.getHeight();

    Font f = g2D.getFont();
    FontMetrics fm = g2D.getFontMetrics(f);

    textWidth = fm.stringWidth(text);
    textHeigth = fm.getHeight();

    xScale = backgroundWidth / (double) textWidth;
    yScale = backgroundHeight / (double) textHeigth;

    if (xScale > yScale) {
        scale = yScale;
    } else {
        scale = xScale;
    }

    g2D.setFont(f.deriveFont(AffineTransform.getScaleInstance(scale, scale)));

    return g2D;
}

private static BufferedImage readImage(File sourceImage) {
    BufferedImage bufferedImage = null;
    try {
        bufferedImage = ImageIO.read(sourceImage);
    } catch (IOException e1) {
        e1.printStackTrace();
    }
    return bufferedImage;
}

private static void writeImage(File destinationImage,
        BufferedImage bufferedImage) {
    try {
        ImageIO.write(bufferedImage, "png", destinationImage);
    } catch (IOException e) {
        e.printStackTrace();
    }

    System.out.println("Image Saved");
}

}

这是要缩放的文本“Lorem ipsum dolor sat amet asdkf sdm”这是通过仿射变换缩放的文本。

output image with font scaled and 'm' letter missed

希望您能帮助我，谢谢

Answer 1

您可以测量字符串的长度并验证它是否适合您的内容。

int lengthInPixel = graphics.getFontMetrics().stringWidth("Lorem ipsum dolor sit amet asdkf sdm")