从SVG文件创建非缓冲的java.awt.Image

时间:2012-11-14 22:47:34

标签: java svg batik

我有一些现有代码,看起来很像Swing & Batik: Create an ImageIcon from an SVG file?

上的解决方案

但我的图像的目的地是PDF,这让我觉得当你放大PDF时,你会看到像素。如果源数据和目标数据都是矢量图形,则应该可以直接渲染。

我们正在使用的库(iText)需要一个java.awt.Image,但我似乎无法弄清楚如何获得一个呈现SVG的java.awt.Image。 Batik有办法做到这一点吗?

1 个答案:

答案 0 :(得分:1)

嗯,这就是我最终做的事情。 java.awt.Image当然是一个死胡同。有一个解决方案是在PdfTemplate中整理ImgTemplate,以便将其用作iText Image

(我必须把它放在知道它的大小的东西上,因为它被用在一张桌子里,否则布局会变得非常疯狂。Image似乎知道这一点。)

public class SvgHelper {
    private final SAXSVGDocumentFactory factory;
    private final GVTBuilder builder;
    private final BridgeContext bridgeContext;

    public SvgHelper() {
        factory = new SAXSVGDocumentFactory(
            XMLResourceDescriptor.getXMLParserClassName());
        UserAgent userAgent = new UserAgentAdapter();
        DocumentLoader loader = new DocumentLoader(userAgent);
        bridgeContext = new BridgeContext(userAgent, loader);
        bridgeContext.setDynamicState(BridgeContext.STATIC);
        builder = new GVTBuilder();
    }

    public Image createSvgImage(PdfContentByte contentByte, URL resource,
                                float maxPointWidth, float maxPointHeight) {
        Image image = drawUnscaledSvg(contentByte, resource);
        image.scaleToFit(maxPointWidth, maxPointHeight);
        return image;
    }

    public Image drawUnscaledSvg(PdfContentByte contentByte, URL resource) {
        GraphicsNode imageGraphics;
        try {
            SVGDocument imageDocument = factory.createSVGDocument(resource.toString());
            imageGraphics = builder.build(bridgeContext, imageDocument);
        } catch (IOException e) {
            throw new RuntimeException("Couldn't load SVG resource", e);
        }

        float width = (float) imageGraphics.getBounds().getWidth();
        float height = (float) imageGraphics.getBounds().getHeight();

        PdfTemplate template = contentByte.createTemplate(width, height);
        Graphics2D graphics = template.createGraphics(width, height);
        try {
            // SVGs can have their corner at coordinates other than (0,0).
            Rectangle2D bounds = imageGraphics.getBounds();

            //TODO: Is this in the right coordinate space even?
            graphics.translate(-bounds.getX(), -bounds.getY());

            imageGraphics.paint(graphics);

            return new ImgTemplate(template);
        } catch (BadElementException e) {
            throw new RuntimeException("Couldn't generate PDF from SVG", e);
        } finally {
            graphics.dispose();
        }
    }
}