/* Taken from http://cairographics.org/samples/ */


#include <cairo.h>
#include <math.h>
#include <stdio.h>

int main(int argc, char *argv[])
{
    char *filename;
    if (argc != 2)
    {
        fprintf (stderr, "Usage: %s OUTPUT_FILENAME\n", argv[0]);
        return 1;
    }
    filename = argv[1];
    double xc = 128.0;
    double yc = 128.0;
    double radius = 100.0;
    double angle1 = 45.0  * (M_PI/180.0);  /* angles are specified */
    double angle2 = 180.0 * (M_PI/180.0);  /* in radians           */

    cairo_surface_t *im = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, xc * 2, yc * 2);
    cairo_t *cr = cairo_create(im);


    cairo_set_line_width (cr, 10.0);
    cairo_arc (cr, xc, yc, radius, angle1, angle2);
    cairo_stroke (cr);

    /* draw helping lines */
    cairo_set_source_rgba (cr, 1, 0.2, 0.2, 0.6);
    cairo_set_line_width (cr, 6.0);

    cairo_arc (cr, xc, yc, 10.0, 0, 2*M_PI);
    cairo_fill (cr);

    cairo_arc (cr, xc, yc, radius, angle1, angle1);
    cairo_line_to (cr, xc, yc);
    cairo_arc (cr, xc, yc, radius, angle2, angle2);
    cairo_line_to (cr, xc, yc);
    cairo_stroke (cr);

    cairo_status_t status = cairo_surface_write_to_png (im, filename);
    cairo_surface_destroy (im);
    if (status != CAIRO_STATUS_SUCCESS) {
        fprintf(stderr, "Could not save png to '%s'\n", filename);
    }

    cairo_destroy(cr);
    return 0;
}