gtk/demos/gtk-demo/textmask.c
2017-01-20 21:37:04 +01:00

83 lines
2.4 KiB
C

/* Pango/Text Mask
*
* This demo shows how to use PangoCairo to draw text with more than
* just a single color.
*/
#include <glib/gi18n.h>
#include <gtk/gtk.h>
static void
draw_text (GtkDrawingArea *da,
cairo_t *cr,
int width,
int height,
gpointer data)
{
cairo_pattern_t *pattern;
PangoLayout *layout;
PangoFontDescription *desc;
cairo_save (cr);
layout = gtk_widget_create_pango_layout (GTK_WIDGET (da), "Pango power!\nPango power!\nPango power!");
desc = pango_font_description_from_string ("sans bold 34");
pango_layout_set_font_description (layout, desc);
pango_font_description_free (desc);
cairo_move_to (cr, 30, 20);
pango_cairo_layout_path (cr, layout);
g_object_unref (layout);
pattern = cairo_pattern_create_linear (0.0, 0.0, width, height);
cairo_pattern_add_color_stop_rgb (pattern, 0.0, 1.0, 0.0, 0.0);
cairo_pattern_add_color_stop_rgb (pattern, 0.2, 1.0, 0.0, 0.0);
cairo_pattern_add_color_stop_rgb (pattern, 0.3, 1.0, 1.0, 0.0);
cairo_pattern_add_color_stop_rgb (pattern, 0.4, 0.0, 1.0, 0.0);
cairo_pattern_add_color_stop_rgb (pattern, 0.6, 0.0, 1.0, 1.0);
cairo_pattern_add_color_stop_rgb (pattern, 0.7, 0.0, 0.0, 1.0);
cairo_pattern_add_color_stop_rgb (pattern, 0.8, 1.0, 0.0, 1.0);
cairo_pattern_add_color_stop_rgb (pattern, 1.0, 1.0, 0.0, 1.0);
cairo_set_source (cr, pattern);
cairo_fill_preserve (cr);
cairo_pattern_destroy (pattern);
cairo_set_source_rgb (cr, 0.0, 0.0, 0.0);
cairo_set_line_width (cr, 0.5);
cairo_stroke (cr);
cairo_restore (cr);
}
GtkWidget *
do_textmask (GtkWidget *do_widget)
{
static GtkWidget *window = NULL;
static GtkWidget *da;
if (!window)
{
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_resizable (GTK_WINDOW (window), TRUE);
gtk_widget_set_size_request (window, 400, 200);
gtk_window_set_title (GTK_WINDOW (window), "Text Mask");
g_signal_connect (window, "destroy",
G_CALLBACK (gtk_widget_destroyed), &window);
da = gtk_drawing_area_new ();
gtk_container_add (GTK_CONTAINER (window), da);
gtk_drawing_area_set_draw_func (GTK_DRAWING_AREA (da), draw_text, NULL, NULL);
}
if (!gtk_widget_get_visible (window))
gtk_widget_show (window);
else
gtk_widget_destroy (window);
return window;
}