Re: Erasing bug in GTK examples/gtkdial

[otaylor redhat com]

Thanks for catching the bug. But I don't like the patch, because
I definitely don't like the hack that it fixes.

I don't know who put the code in to erase the dial that way - I
guess it's:

=======
Sat Nov 13 22:30:29 GMT 1999 Tony Gale  <gale gtk org>

	* docs/gtkfaq.sgml: threads example from Erik Mouw.
	New question on GtkLabel background colors.

	* docs/gtk_tut.sgml:
	  - Correct the example code callback
	    function definitions.
	  - Update the gtkdial example code, from Frans van Schaik.
	  - Update setselection.c to current API.
=======

But it needs to be removed. This is supposed to be clean _example_
code, not hack-around-sort-of-reduce-flicker code.

Plus, in GTK+-2.0, GTK+ makes handling no-flicker with backing
store really easy.

Regards,
                                        Owen


BJerrick easystreet com writes:

>     The pointer in examples/gtkdial (gtk+-1.2.6 through gtk+-snap20000810,
> at least) doesn't erase completely when moved.  This is due to two
> bugs in the widget's code, gtkdial.c .
> 
>     A fix for both is below.  The added comment explains the first.
> The second changes the 'fill' argument of the gtk_draw_polygon() that
> does the erasing to match that used for drawing (TRUE, i.e., filled).
> 
> Bruce Jerrick
> Portland, Oregon, USA
> email:   bjerrick easystreet com
> 
> 
> --- examples/gtkdial/gtkdial.c.0	Fri Aug 18 05:29:10 2000
> +++ examples/gtkdial/gtkdial.c	Wed Oct 11 23:48:58 2000
> @@ -322,21 +322,26 @@
>    points[4].y = points[0].y;
>  
>    blankstyle = gtk_style_new ();
> +  /*
> +   * Use bg_gc for all gc's used by gtk_default_draw_polygon()
> +   *  (bg_gc, dark_gc, light_gc, black_gc).
> +   * Widget's style was set using GTK_STATE_ACTIVE, so use that bg_gc.
> +   */
>    blankstyle->bg_gc[GTK_STATE_NORMAL] =
> -                widget->style->bg_gc[GTK_STATE_NORMAL];
> +                widget->style->bg_gc[GTK_STATE_ACTIVE];
>    blankstyle->dark_gc[GTK_STATE_NORMAL] =
> -                widget->style->bg_gc[GTK_STATE_NORMAL];
> +                widget->style->bg_gc[GTK_STATE_ACTIVE];
>    blankstyle->light_gc[GTK_STATE_NORMAL] =
> -                widget->style->bg_gc[GTK_STATE_NORMAL];
> +                widget->style->bg_gc[GTK_STATE_ACTIVE];
>    blankstyle->black_gc =
> -                widget->style->bg_gc[GTK_STATE_NORMAL];
> +                widget->style->bg_gc[GTK_STATE_ACTIVE];
>  
>    gtk_draw_polygon (blankstyle,
>                      widget->window,
>                      GTK_STATE_NORMAL,
>                      GTK_SHADOW_OUT,
>                      points, 5,
> -                    FALSE);
> +                    TRUE);
>  
>    gtk_style_unref(blankstyle);