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javapdfpdfbox

Can't Get Path to Fill in PDFBox

I am using PDF box to attempt to create some rectangles with curved edges. After finally figuring out how to use Bézier curves, I was able to get a shape that I liked. My problem now is that I cannot figure out how to fill it. I've tried closing the path in random spots, drawing the shape using only Bézier curves, stroking the path at random spots, closing the path at random spots, but it still won't fill the whole thing. It only seems to fill the rounded edges of the curve. Could anyone please let me know what I am doing wrong? Thanks so much. generator is an object that I am using to fetch the horizontal and vertical positions currently set in the page. The horizontal and vertical position values do not change in this example (the horizontal position is 200, and the vertical 240). Here is the code that I am using (sorry for the magic numbers in there)

Here is the resulting image in the PDF page, which won't fill in for some reason:

resulting image in the PDF page, which won't fill in for some reason

//Creating PDF document object 
PDDocument document = new PDDocument(); 
//Creating the PDDocumentInformation object 
PDDocumentInformation pdd = document.getDocumentInformation();
generator.drawRectangleWithCurvedBorders(200, 400, cs, generator);



public void drawRectangleWithCurvedBorders(int width, int height, PDPageContentStream contentStream, XClass generator) throws IOException
    {
        contentStream.setStrokingColor( Color.BLACK );
        contentStream.setNonStrokingColor( Color.BLACK );

        // bottom of rectangle
        contentStream.moveTo(generator.getHorizontalPosition() - 0.5f, generator.getVerticalPosition() );
        contentStream.lineTo(generator.getHorizontalPosition() + width + 0.5f, generator.getVerticalPosition() );
        contentStream.moveTo(generator.getHorizontalPosition() + width, generator.getVerticalPosition() );

        contentStream.curveTo(generator.getHorizontalPosition() + width + 5.9f, generator.getVerticalPosition() + 0.14f,
                              generator.getHorizontalPosition() + width + 11.06f, generator.getVerticalPosition() + 5.16f,
                              generator.getHorizontalPosition() + width + 10.96f, generator.getVerticalPosition() + 10);

        // left of rectangle
        contentStream.moveTo(generator.getHorizontalPosition(), generator.getVerticalPosition() );
        contentStream.curveTo(generator.getHorizontalPosition() - 5.9f, generator.getVerticalPosition() + 0.14f,
                              generator.getHorizontalPosition() - 11.06f, generator.getVerticalPosition() + 5.16f,
                              generator.getHorizontalPosition() - 10.96f, generator.getVerticalPosition() + 10);
        contentStream.moveTo(generator.getHorizontalPosition() - 10.96f, generator.getVerticalPosition() + 10 - 0.5f);
        contentStream.lineTo(generator.getHorizontalPosition() - 10.96f, generator.getVerticalPosition() + height + 0.5f );


        // right of rectangle       
        contentStream.moveTo(generator.getHorizontalPosition() + width + 10.96f, generator.getVerticalPosition() + 10 - 0.5f);
        contentStream.lineTo(generator.getHorizontalPosition() + width + 10.96f, generator.getVerticalPosition() + height + 0.5f);
        contentStream.moveTo(generator.getHorizontalPosition() + width, generator.getVerticalPosition() + height + 10);
        contentStream.curveTo(generator.getHorizontalPosition() + width + 5.9f, generator.getVerticalPosition() + height + 0.14f + 10,
                  generator.getHorizontalPosition() + width + 11.06f, generator.getVerticalPosition() + height - 5.16f + 10,
                  generator.getHorizontalPosition() + width + 10.96f, generator.getVerticalPosition() + height);

        // top of rectangle
        contentStream.moveTo(generator.getHorizontalPosition() + width + 0.5f, generator.getVerticalPosition() + height + 10);
        contentStream.lineTo(generator.getHorizontalPosition() - 0.5f, generator.getVerticalPosition() + height + 10);
        contentStream.moveTo(generator.getHorizontalPosition(), generator.getVerticalPosition() + height + 10);
        contentStream.curveTo(generator.getHorizontalPosition() - 5.9f, generator.getVerticalPosition() + height + 0.14f + 10,
                  generator.getHorizontalPosition() - 11.06f, generator.getVerticalPosition() + height - 5.16f + 10,
                  generator.getHorizontalPosition() - 10.96f, generator.getVerticalPosition() + height);

        contentStream.closePath();
        contentStream.fill();
    }
Solution

  • As Tilman already said in a comment to the question, the problem are the many moveTo() instructions. Indeed, each moveTo starts a new sub path and each sub path implies a separate fill area. Depending on the filling variant and the subpath orientations, intersections of those subpaths might actually be excluded from being filled.

    Thus, to create a filled rectangle with curved borders as outlined by the OP, one should rearrange the path building instructions so that they outline the rectangle without a moveTo interrupting the flow, e.g. like this:

    try (   PDDocument document = new PDDocument()  ) {
    PDPage page = new PDPage();
    document.addPage(page);
    try (   PDPageContentStream contentStream = new PDPageContentStream(document, page)    ) {
        float x = 100;
        float y = 100;
        float width = 200;
        float height = 300;

        contentStream.setStrokingColor( Color.BLACK );
        contentStream.setNonStrokingColor( Color.BLACK );

        contentStream.moveTo(x, y);

        // bottom of rectangle, left to right
        contentStream.lineTo(x + width, y );
        contentStream.curveTo(x + width + 5.9f, y + 0.14f,
                x + width + 11.06f, y + 5.16f,
                x + width + 10.96f, y + 10);

        // right of rectangle, bottom to top
        contentStream.lineTo(x + width + 10.96f, y + height);
        contentStream.curveTo(x + width + 11.06f, y + height - 5.16f + 10,
                x + width + 5.9f, y + height + 0.14f + 10,
                x + width, y + height + 10);

        // top of rectangle, right to left
        contentStream.lineTo(x, y + height + 10);
        contentStream.curveTo(x - 5.9f, y + height + 0.14f + 10,
                x - 11.06f, y + height - 5.16f + 10,
                x - 10.96f, y + height);

        // left of rectangle, top to bottom
        contentStream.lineTo(x - 10.96f, y + 10);
        contentStream.curveTo(x - 11.06f, y + 5.16f,
                x - 5.9f, y + 0.14f,
                x, y);

        contentStream.closePath();
        contentStream.fill();
    }
    document.save(new File("CurvedBorderRectangleLikeMaht33n-improved.pdf"));
}

    (CurvedBorderRectangle test testLikeMaht33nImproved)

    (I don't have that XClass generator object, so I used two float variables x and y instead.)

    The result, as desired:

    screen shot