Pixbuf / Pixmap

[Daniel Campos <danielcampos netcourrier com>]

Hi:


I've written this little example to show my problem. Sometimes I need to
load PNG's and other files from a pixbuf, then store it in a pixmap, and
then put it again in a pixbuf, as some functions as gtk_window_set_icon
just accepts a pixbuf as parameter. The problem is that the new icon has
not transparent background. I suppose I have to perform any combination
between the pixmap and the mask, or maybe change the graphics context of
the pixmap, but after ten hours I can't obtain anything. I've tried all
I could imagine reading Gdk and GdkPixbuf api docs, but nothing...

Could anyone help me, please?


#include <gtk/gtk.h>
#include <stdio.h>

int main (int argc,char *argv[])
{
	GtkWidget *window;
	GtkHBox *box;
	GtkImage *image1,*image2,*image3;
	GdkPixbuf *pixbuf,*pixbuf2;
	GdkPixmap *pixmap;
	GdkBitmap *bitmap;
	GdkScreen*  scr;
	gint depth;
	gint myw,myh;
		
	gtk_init (&argc, &argv);
	
	window=gtk_window_new(GTK_WINDOW_TOPLEVEL);
	box=gtk_hbox_new(TRUE,1);
	
	/* I read a PNG icon from a file */
	pixbuf=gdk_pixbuf_new_from_file("execution.png",NULL);
	
	/* Values to create a pixmap and a bitmap */
	myw=gdk_pixbuf_get_width(pixbuf);
	myh=gdk_pixbuf_get_height(pixbuf);
	scr=gdk_screen_get_default();
	depth=(gdk_screen_get_system_visual(scr))->depth;
	
	/* I create the pixmap to receive the image and the bitmap to */
	/* receive the mask */
	pixmap=gdk_pixmap_new(NULL,myw,myh,depth);
	bitmap=gdk_pixmap_new(NULL,myw,myh,1);
	gdk_drawable_set_colormap (pixmap,gdk_colormap_get_system ());
	gdk_pixbuf_render_pixmap_and_mask(pixbuf,&pixmap,&bitmap,0);
	                              
	pixbuf2=gdk_pixbuf_get_from_drawable(NULL,pixmap,NULL,0,0,0,0,myw,myh);
	
	image1=gtk_image_new_from_pixmap(pixmap,NULL);
	image2=gtk_image_new_from_pixbuf(pixbuf2);
	image3=gtk_image_new_from_pixbuf(pixbuf);
	
	gtk_box_pack_start(box,image1,FALSE,FALSE,0);
	gtk_box_pack_start(box,image2,FALSE,FALSE,0);
	gtk_box_pack_start(box,image3,FALSE,FALSE,0);
	
	gtk_container_add(GTK_CONTAINER(window),GTK_WIDGET(box));
	gtk_window_set_icon(window,pixbuf2);
	gtk_widget_show_all(GTK_WIDGET(window));
	gtk_main();
	return 0;
}



-- 
Daniel Campos <danielcampos netcourrier com>