java - java中缩放图像

Question

我需要创建一个 Web 服务，该服务将根据用户的姓名缩写生成用户的图标。类似于 this Android 项目，但在服务器端使用 Java。

该图像的大小应该是动态的。我已经有了可以创建一个中间有两个字母的矩形的代码，但它不会缩放文本。

这是迄今为止我的代码:

public BufferedImage getAbbreviationImage(int height, int width, String abbreviation) throws IOException {

    int centerX = width/2;
    int centerY = height/2;

    BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.SCALE_SMOOTH);

    Graphics2D g = bufferedImage.createGraphics();
    Font font = new Font("Helvetica", Font.BOLD, 90);
    g.setFont(font);
    g.setRenderingHint(
            RenderingHints.KEY_TEXT_ANTIALIASING,
            RenderingHints.VALUE_TEXT_ANTIALIAS_LCD_HRGB);

    g.setColor(Color.decode("#3f404c"));
    g.fillRect(0, 0, width, height);


    // get the bounds of the string to draw.
    FontMetrics fontMetrics = g.getFontMetrics();
    Rectangle stringBounds = fontMetrics.getStringBounds(abbreviation, g).getBounds();

    FontRenderContext renderContext = g.getFontRenderContext();
    GlyphVector glyphVector = font.createGlyphVector(renderContext, abbreviation);
    Rectangle visualBounds = glyphVector.getVisualBounds().getBounds();

    // calculate the lower left point at which to draw the string. note that this we
    // give the graphics context the y corridinate at which we want the baseline to
    // be placed. use the visual bounds height to center on in conjuction with the
    // position returned in the visual bounds. the vertical position given back in the
    // visualBounds is a negative offset from the basline of the text.
    int textX = centerX - stringBounds.width/2;
    int textY = centerY - visualBounds.height/2 - visualBounds.y;

    g.setColor(Color.WHITE);
    g.drawString(abbreviation, textX, textY);

    g.dispose();

    return bufferedImage;
}

是否有任何 Java 库可以执行类似的操作，这样我就不必编写自己的代码了。如果没有，那么根据图像大小缩放文本的最佳方法是什么？

学分:我的一些代码取自 HERE

Answer 1

您需要设置附加到 Graphics2D 对象的字体大小。来自甲骨文文档:

public abstract void drawString(String str,
              int x,
              int y)

Renders the text of the specified String, using the current text attribute state in the Graphics2D context

您应该适当设置所使用的字体大小以匹配矩形的尺寸。像这样的事情:

int lFontSize = 90 * (originalRectangleWidth / newRectangleWidth);
Font font = new Font("Helvetica", Font.BOLD, lFontSize );

地点:

• 90 是引用字体大小(这是您在示例中设置的值)

• originalRectangleWidth 是当字体大小为 90 时看起来不错时使用的矩形的大小

• newRectangleWidth 将是新的矩形宽度

引用文献: Graphics2D (oracle ref) Font (oracle ref)