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#include <math.h>
#include <pango/pangocairo.h>
static void
draw_text (cairo_t *cr)
{
#define RADIUS 150
#define N_WORDS 10
#define FONT "Sans Bold 27"
PangoLayout *layout;
PangoFontDescription *desc;
int i;
/* Center coordinates on the middle of the region we are drawing
*/
cairo_translate (cr, RADIUS, RADIUS);
/* Create a PangoLayout, set the font and text */
layout = pango_cairo_create_layout (cr);
pango_layout_set_text (layout, "Text", -1);
desc = pango_font_description_from_string (FONT);
pango_layout_set_font_description (layout, desc);
pango_font_description_free (desc);
/* Draw the layout N_WORDS times in a circle */
for (i = 0; i < N_WORDS; i++)
{
int width, height;
double angle = (360. * i) / N_WORDS;
double red;
cairo_save (cr);
/* Gradient from red at angle == 60 to blue at angle == 300 */
red = (1 + cos ((angle - 60) * G_PI / 180.)) / 2;
cairo_set_rgb_color (cr, red, 0, 1.0 - red);
cairo_rotate (cr, angle * G_PI / 180.);
/* Inform Pango to re-layout the text with the new transformation */
pango_cairo_update_layout (cr, layout);
pango_layout_get_size (layout, &width, &height);
cairo_move_to (cr, - ((double)width / PANGO_SCALE) / 2, - RADIUS);
pango_cairo_show_layout (cr, layout);
cairo_restore (cr);
}
/* free the layout object */
g_object_unref (layout);
}
int main (int argc, char **argv)
{
cairo_t *cr;
FILE *f;
if (argc != 2)
{
g_printerr ("Usage: cairosimple OUTPUT_FILENAME\n");
return 1;
}
f = fopen (argv[1], "w");
if (!f)
{
g_printerr ("Usage: cannot open '%s'\n", argv[1]);
return 1;
}
cr = cairo_create();
cairo_set_target_png (cr, f,
CAIRO_FORMAT_ARGB32,
2 * RADIUS, 2 * RADIUS);
cairo_set_rgb_color (cr, 1.0, 1.0, 1.0);
cairo_rectangle (cr, 0, 0, 2 * RADIUS, 2 * RADIUS);
cairo_fill (cr);
draw_text (cr);
cairo_destroy (cr);
fclose (f);
return 0;
}
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