demos/testpixbuf-scale.c

   1 #include "config.h"
   2 #include <gtk/gtk.h>
   3
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6
   7 GdkInterpType interp_type = GDK_INTERP_BILINEAR;
   8 int overall_alpha = 255;
   9 GdkPixbuf *pixbuf;
  10 GtkWidget *darea;
  11
  12 void
  13 set_interp_type (GtkWidget *widget, gpointer data)
  14 {
  15   guint types[] = { GDK_INTERP_NEAREST,
  16                     GDK_INTERP_BILINEAR,
  17                     GDK_INTERP_TILES,
  18                     GDK_INTERP_HYPER };
  19
  20   interp_type = types[gtk_combo_box_get_active (GTK_COMBO_BOX (widget))];
  21   gtk_widget_queue_draw (darea);
  22 }
  23
  24 void
  25 overall_changed_cb (GtkAdjustment *adjustment, gpointer data)
  26 {
  27   if (adjustment->value != overall_alpha)
  28     {
  29       overall_alpha = adjustment->value;
  30       gtk_widget_queue_draw (darea);
  31     }
  32 }
  33
  34 gboolean
  35 expose_cb (GtkWidget *widget, GdkEventExpose *event, gpointer data)
  36 {
  37   GdkPixbuf *dest;
  38
  39   gdk_window_set_back_pixmap (widget->window, NULL, FALSE);
  40
  41   dest = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, event->area.width, event->area.height);
  42
  43   gdk_pixbuf_composite_color (pixbuf, dest,
  44                               0, 0, event->area.width, event->area.height,
  45                               -event->area.x, -event->area.y,
  46                               (double) widget->allocation.width / gdk_pixbuf_get_width (pixbuf),
  47                               (double) widget->allocation.height / gdk_pixbuf_get_height (pixbuf),
  48                               interp_type, overall_alpha,
  49                               event->area.x, event->area.y, 16, 0xaaaaaa, 0x555555);
  50
  51   gdk_draw_pixbuf (widget->window, widget->style->fg_gc[GTK_STATE_NORMAL], dest,
  52                    0, 0, event->area.x, event->area.y,
  53                    event->area.width, event->area.height,
  54                    GDK_RGB_DITHER_NORMAL, event->area.x, event->area.y);
  55
  56   g_object_unref (dest);
  57
  58   return TRUE;
  59 }
  60
  61 extern void pixbuf_init();
  62
  63 int
  64 main(int argc, char **argv)
  65 {
  66         GtkWidget *window, *vbox;
  67         GtkWidget *combo_box;
  68         GtkWidget *alignment;
  69         GtkWidget *hbox, *label, *hscale;
  70         GtkAdjustment *adjustment;
  71         GtkRequisition scratch_requisition;
  72         const gchar *creator;
  73         GError *error;
  74
  75         pixbuf_init ();
  76
  77         gtk_init (&argc, &argv);
  78
  79         if (argc != 2) {
  80                 fprintf (stderr, "Usage: testpixbuf-scale FILE\n");
  81                 exit (1);
  82         }
  83
  84         error = NULL;
  85         pixbuf = gdk_pixbuf_new_from_file (argv[1], &error);
  86         if (!pixbuf) {
  87                 fprintf (stderr, "Cannot load image: %s\n",
  88                          error->message);
  89                 g_error_free (error);
  90                 exit(1);
  91         }
  92
  93         creator = gdk_pixbuf_get_option (pixbuf, "tEXt::Software");
  94         if (creator)
  95                 g_print ("%s was created by '%s'\n", argv[1], creator);
  96
  97         window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  98         g_signal_connect (window, "destroy",
  99                           G_CALLBACK (gtk_main_quit), NULL);
 100
 101         vbox = gtk_vbox_new (FALSE, 0);
 102         gtk_container_add (GTK_CONTAINER (window), vbox);
 103
 104         combo_box = gtk_combo_box_new_text ();
 105
 106         gtk_combo_box_append_text (GTK_COMBO_BOX (combo_box), "NEAREST");
 107         gtk_combo_box_append_text (GTK_COMBO_BOX (combo_box), "BILINEAR");
 108         gtk_combo_box_append_text (GTK_COMBO_BOX (combo_box), "TILES");
 109         gtk_combo_box_append_text (GTK_COMBO_BOX (combo_box), "HYPER");
 110
 111         gtk_combo_box_set_active (GTK_COMBO_BOX (combo_box), 1);
 112
 113         g_signal_connect (combo_box, "changed",
 114                           G_CALLBACK (set_interp_type),
 115                           NULL);
 116
 117         alignment = gtk_alignment_new (0.0, 0.0, 0.0, 0.5);
 118         gtk_box_pack_start (GTK_BOX (vbox), alignment, FALSE, FALSE, 0);
 119
 120         hbox = gtk_hbox_new (FALSE, 4);
 121         gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
 122
 123         label = gtk_label_new ("Overall Alpha:");
 124         gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
 125
 126         adjustment = GTK_ADJUSTMENT (gtk_adjustment_new (overall_alpha, 0, 255, 1, 10, 0));
 127         g_signal_connect (adjustment, "value_changed",
 128                           G_CALLBACK (overall_changed_cb), NULL);
 129
 130         hscale = gtk_hscale_new (adjustment);
 131         gtk_scale_set_digits (GTK_SCALE (hscale), 0);
 132         gtk_box_pack_start (GTK_BOX (hbox), hscale, TRUE, TRUE, 0);
 133
 134         gtk_container_add (GTK_CONTAINER (alignment), combo_box);
 135         gtk_widget_show_all (vbox);
 136
 137         /* Compute the size without the drawing area, so we know how big to make the default size */
 138         gtk_widget_size_request (vbox, &scratch_requisition);
 139
 140         darea = gtk_drawing_area_new ();
 141         gtk_box_pack_start (GTK_BOX (vbox), darea, TRUE, TRUE, 0);
 142
 143         g_signal_connect (darea, "expose_event",
 144                           G_CALLBACK (expose_cb), NULL);
 145
 146         gtk_window_set_default_size (GTK_WINDOW (window),
 147                                      gdk_pixbuf_get_width (pixbuf),
 148                                      scratch_requisition.height + gdk_pixbuf_get_height (pixbuf));
 149
 150         gtk_widget_show_all (window);
 151
 152         gtk_main ();
 153
 154         return 0;
 155 }