svg-surface.cc

An example of using Cairo::SvgSurface class to render to SVG

/* M_PI is defined in math.h in the case of Microsoft Visual C++, Solaris,
 * et. al.
 */
 
#include <string>
#include <iostream>
#include <cairommconfig.h>
#include <cairomm/context.h>
#include <cairomm/surface.h>
 
#include <cmath>
 
int main()
{
#ifdef CAIRO_HAS_SVG_SURFACE
 
    std::string filename = "image.svg";
    double width = 600;
    double height = 400;
    auto surface =
        Cairo::SvgSurface::create(filename, width, height);
 
    auto cr = Cairo::Context::create(surface);
 
    cr->save(); // save the state of the context
    cr->set_source_rgb(0.86, 0.85, 0.47);
    cr->paint();    // fill image with the color
    cr->restore();  // color is back to black now
 
    cr->save();
    // draw a border around the image
    cr->set_line_width(20.0);    // make the line wider
    cr->rectangle(0.0, 0.0, cairo_image_surface_get_width(surface->cobj()), height);
    cr->stroke();
 
    cr->set_source_rgba(0.0, 0.0, 0.0, 0.7);
    // draw a circle in the center of the image
    cr->arc(width / 2.0, height / 2.0, 
            height / 4.0, 0.0, 2.0 * M_PI);
    cr->stroke();
 
    // draw a diagonal line
    cr->move_to(width / 4.0, height / 4.0);
    cr->line_to(width * 3.0 / 4.0, height * 3.0 / 4.0);
    cr->stroke();
    cr->restore();
 
    cr->show_page();
 
    std::cout << "Wrote SVG file \"" << filename << "\"" << std::endl;
    return 0;
 
#else
 
    std::cout << "You must compile cairo with SVG support for this example to work."
        << std::endl;
    return 1;
 
#endif
}