/* * * Sample Code for Gtk+ Programming in C, 1st Edition, Prentice Hall * * Copyright 2000 - 2002 Syd Logan, All Rights Reserved * * This code is distributed without warranty. You are free to use this * code for any purpose, however, if this code is republished or * redistributed in its original form, as hardcopy or electronically, * then you must include this copyright notice along with the code. * * Questions or comments regarding this code or any bugs it contains can * be directed to the author via e-mail at slogan@cts.com **/#include <gtk/gtk.h>#define RED 	1#define GREEN 	2#define BLUE 	4 typedef struct piece {  int x;			// position of the piece  int y;			  guint32 time;		// time the piece was added  unsigned char color;	// its color} Piece;typedef struct cleardata {  GtkWidget *w;  GList **list;} ClearData; static GtkWidget *gRedPmap, *gGreenPmap, *gBluePmap;static unsigned char gColor = RED;static GtkWidget*NewPixmap( char *filename, GdkWindow *window, GdkColor *background ){  GtkWidget *wpixmap;  GdkPixmap *pixmap;  GdkBitmap *mask;  pixmap = gdk_pixmap_create_from_xpm( window, &mask, background,    filename );  wpixmap = gtk_pixmap_new( pixmap, mask );  return wpixmap;}static voidSetColor( GtkWidget *widget, gpointer arg ){  gColor = (unsigned long ) arg & 0xf;}static voidClearDrawing( GtkWidget *widget, gpointer arg ){  ClearData *p = (ClearData *) arg;  GList **list = p->list;  GList *tmp_list;  for (tmp_list = *list; tmp_list; tmp_list = tmp_list->next)    g_free(tmp_list->data);  g_list_free(*list);  *list = (GList *) NULL;  gdk_window_clear( p->w->window );}static intCompFunc( gconstpointer a, gconstpointer b ){  Piece *piece1, *piece2;	  piece1 = (Piece *) a;	  piece2 = (Piece *) b;	  if ( piece1->time < piece2->time )    return FALSE;  return TRUE;}static gintButtonPress( GtkWidget *widget, GdkEventButton *event, gpointer arg ){  ClearData *p = (ClearData *) arg;  GList **items = (GList **) p->list;  GtkPixmap *pixmap;  Piece *piece;  piece = (Piece *) malloc( sizeof( Piece ) );  piece->color = gColor;  piece->x = (gint) event->x;  piece->y = (gint) event->y;  piece->time = gdk_event_get_time( (GdkEvent *) event );  *items = g_list_insert_sorted( *items, piece, CompFunc );  switch ( piece->color ) {    case RED:      pixmap = GTK_PIXMAP( gRedPmap );      break;    case GREEN:      pixmap = GTK_PIXMAP( gGreenPmap );      break;    case BLUE:      pixmap = GTK_PIXMAP( gBluePmap );      break;  }  gdk_draw_pixmap( widget->window, widget->style->black_gc,    pixmap->pixmap, 0, 0, piece->x, piece->y, -1, -1 );}static gintHandleExpose( GtkWidget *widget, GdkEventExpose *event, gpointer arg ){  GList **p = (GList **) arg, *list = (GList *) *p;  GdkRectangle rect, dest;  GtkPixmap *pixmap;  Piece *piece, *temp;  int i;  for ( i = 0; *p != (GList *) NULL; i++, *p = g_list_next( *p ) ) {    piece = g_list_nth_data( (GList *) list, i );    rect.x = piece->x;     rect.y = piece->y;    rect.width = rect.height = 20;    if ( gdk_rectangle_intersect( &rect, &event->area, &dest ) == TRUE ) {      switch ( piece->color ) {        case RED:          pixmap = GTK_PIXMAP( gRedPmap );          break;        case GREEN:          pixmap = GTK_PIXMAP( gGreenPmap );          break;        case BLUE:          pixmap = GTK_PIXMAP( gBluePmap );          break;        default:          continue;      }      gdk_gc_set_clip_rectangle( widget->style->black_gc, &event->area );      gdk_draw_pixmap( widget->window, widget->style->black_gc,         pixmap->pixmap, 0, 0, piece->x, piece->y, -1, -1 );      gdk_gc_set_clip_rectangle( widget->style->black_gc, NULL );    }  }  *p = list;}main( int argc, char *argv[] ){  GtkWidget *dialog, *button, *drawing, *toolbar;  GList *items = (GList *) NULL;  ClearData cd;  gtk_init( &argc, &argv );  dialog = gtk_dialog_new();  gtk_window_position( GTK_WINDOW( dialog ), GTK_WIN_POS_MOUSE );  gtk_widget_show( dialog );  toolbar = gtk_toolbar_new( GTK_ORIENTATION_HORIZONTAL, GTK_TOOLBAR_BOTH );  gRedPmap = NewPixmap( "red.xpm", dialog->window,     &dialog->style->bg[GTK_STATE_NORMAL] ),  gtk_toolbar_append_item( GTK_TOOLBAR( toolbar ), "Red",     "Draw red square", NULL, gRedPmap,    (GtkSignalFunc) SetColor, (gpointer) RED );      gGreenPmap = NewPixmap( "green.xpm", dialog->window,     &dialog->style->bg[GTK_STATE_NORMAL] ),  gtk_toolbar_append_item( GTK_TOOLBAR( toolbar ), "Green",     "Draw green square", NULL, gGreenPmap,    (GtkSignalFunc) SetColor, (gpointer) GREEN );      gBluePmap = NewPixmap( "blue.xpm", dialog->window,     &dialog->style->bg[GTK_STATE_NORMAL] ),  gtk_toolbar_append_item( GTK_TOOLBAR( toolbar ), "Blue",     "Draw blue square", NULL, gBluePmap,    (GtkSignalFunc) SetColor, (gpointer) BLUE );      gtk_box_pack_start( GTK_BOX( GTK_DIALOG( dialog )->vbox ), toolbar,     FALSE, TRUE, 0 );  drawing = gtk_drawing_area_new();  gtk_drawing_area_size( GTK_DRAWING_AREA( drawing ), 320, 200 );  gtk_signal_connect( GTK_OBJECT( drawing ), "expose_event",    GTK_SIGNAL_FUNC( HandleExpose ), &items );  gtk_widget_set_events( drawing,     GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK);  cd.w = drawing;  cd.list = &items;  gtk_signal_connect( GTK_OBJECT( drawing ), "button_press_event",    GTK_SIGNAL_FUNC( ButtonPress ), &cd );	  gtk_box_pack_start( GTK_BOX( GTK_DIALOG( dialog )->vbox ), drawing,     TRUE, TRUE, 0 );  button = gtk_button_new_with_label( "Clear" );  gtk_box_pack_start( GTK_BOX( GTK_DIALOG( dialog )->action_area ),     button, TRUE, FALSE, 0 );  gtk_signal_connect( GTK_OBJECT( button ), "clicked",    GTK_SIGNAL_FUNC( ClearDrawing ), &cd );  gtk_widget_show_all( dialog );  gtk_main();}