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/* Simple example to use pangocairo to render rotated text */
#include <math.h>
#include <pango/pangocairo.h>
static void
draw_text (cairo_t *cr)
{
#define RADIUS 200
#define N_WORDS 8
#define FONT_WITH_MANUAL_SIZE "Times new roman,Sans"
#define FONT_SIZE 36
#define DEVICE_DPI 72
/* The following number applies a cairo CTM. Tests for
* https://bugzilla.gnome.org/show_bug.cgi?id=700592
*/
#define TWEAKABLE_SCALE ((double) 0.1)
PangoLayout *layout;
PangoFontDescription *desc;
int i;
/* Center coordinates on the middle of the region we are drawing
*/
cairo_translate (cr, RADIUS / TWEAKABLE_SCALE, RADIUS / TWEAKABLE_SCALE);
/* Create a PangoLayout, set the font and text */
layout = pango_cairo_create_layout (cr);
pango_layout_set_text (layout, "Test\nسَلام", -1);
desc = pango_font_description_from_string (FONT_WITH_MANUAL_SIZE);
pango_font_description_set_absolute_size(desc, FONT_SIZE * DEVICE_DPI * PANGO_SCALE / (72.0 * TWEAKABLE_SCALE));
//pango_font_description_set_size(desc, 27 * PANGO_SCALE / TWEAKABLE_SCALE);
printf("PANGO_SCALE = %d\n", PANGO_SCALE);
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 == 240 */
red = (1 + cos ((angle - 60) * G_PI / 180.)) / 2;
cairo_set_source_rgb (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) / 2.0) , (- RADIUS) / TWEAKABLE_SCALE);
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;
char *filename;
cairo_status_t status;
cairo_surface_t *surface;
if (argc != 2)
{
g_printerr ("Usage: cairosimple OUTPUT_FILENAME\n");
return 1;
}
filename = argv[1];
surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
2 * RADIUS, 2 * RADIUS);
cr = cairo_create (surface);
cairo_scale(cr, 1 * TWEAKABLE_SCALE, 1 * TWEAKABLE_SCALE);
cairo_set_source_rgb (cr, 1.0, 1.0, 1.0);
cairo_paint (cr);
draw_text (cr);
cairo_destroy (cr);
status = cairo_surface_write_to_png (surface, filename);
cairo_surface_destroy (surface);
if (status != CAIRO_STATUS_SUCCESS)
{
g_printerr ("Could not save png to '%s'\n", filename);
return 1;
}
return 0;
}
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