Exemple #1
0
func main() {
	log.SetFlags(0)

	var err error
	img, err = getImage()
	if err != nil {
		log.Fatalln(err)
	}

	fmt.Println("Using libcairo:", cairo.Version())

	count := 0
	logerr := func(name string, err error) {
		count++
		log.Printf("%s: %s", name, err)
	}

	for _, example := range examples {
		nm := example.Name

		outname := nm + ".pdf"

		outfile, err := os.Create(outname)
		if err != nil {
			logerr(nm, err)
			continue
		}
		defer outfile.Close()

		surface, err := pdf.New(outfile, 595, 842) //A4
		if err != nil {
			logerr(nm, err)
			continue
		}
		defer surface.Close()

		context, err := cairo.New(surface)
		if err != nil {
			logerr(nm, err)
			continue
		}
		defer context.Close()

		if err = example.Run(context); err != nil {
			logerr(nm, err)
			continue
		}

		if err = context.Err(); err != nil {
			logerr(nm, err)
		}
	}

	fmt.Printf("%d of %d examples failed\n", count, len(examples))
}
Exemple #2
0
//When generating landscape PostScript output the surface should not be created
//with a width greater than the height. Instead create the surface
//with a height greater than the width and rotate the cairo drawing context.
//The "%PageOrientation" DSC comment is used by PostScript viewers to indicate
//the orientation of the page.
//
//The steps to create a landscape page are:
//Set the page size to a portrait size.
//Rotate user space 90 degrees counterclockwise and move the origin
//to the correct location.
//Insert the "%PageOrientation: Landscape" DSC comment.
func Example_landscape() {
	draw := func(c *cairo.Context, text string, width, height int) error {
		const Border = 50
		border := cairo.Pt(Border, Border)
		size := cairo.Pt(float64(width), float64(height))

		c.
			Rectangle(cairo.Rectangle{border, border.Sub(size)}).
			SetLineWidth(2).
			Stroke()

		c.
			SelectFont("Sans", 0, 0).
			SetFontSize(60).
			MoveTo(cairo.Pt(200, float64(height)/3)).
			ShowText(text)

		c.
			SetFontSize(18).
			MoveTo(cairo.Pt(120, float64(height)*2/3.)).
			ShowText(fmt.Sprintf("Width: %d points\t\tHeight: %d points"))

		return nil
	}

	//A4
	const (
		PageWidth  = 595
		PageHeight = 842
	)
	surface, err := New(os.Stdout, PageWidth, PageHeight, false, nil, nil)
	if err != nil {
		log.Println(err)
		return
	}
	defer surface.Close()

	c, err := cairo.New(surface)
	if err != nil {
		log.Println(err)
		return
	}
	defer c.Close()

	//Print portrait page
	surface.AddComment("PageOrientation", "Portrait")
	err = draw(c, "Portrait", PageWidth, PageHeight)
	if err != nil {
		log.Println(err)
		return
	}
	surface.ShowPage()

	//Print landscape page
	surface.AddComment("PageOrientation", "Landscape")

	//Move the origin to landscape origin and rotate counterclockwise
	c.
		Translate(cairo.Pt(0, PageHeight)).
		Rotate(-math.Pi / 2)

	err = draw(c, "Landscape", PageHeight, PageWidth)
	if err != nil {
		log.Println(err)
		return
	}
	surface.ShowPage()
}