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/* 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;
}
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