I am having trouble rendering an ImageSurface to an X11 display.  My problem seems to be with only certain sizes and may possibly be related to my graphics card and driver. In the code below, I took the "Image" snippet from the cairo-demo package and broke it out into a simple program.  I then took the png file "romedalen.png" and sc.aled and saved it using Gimp such that I had a total of five files of pixel sizes 100x100, 256x192(original size), 300x300, 400x300, and 400x400. (BTW, the cairo_snippets_gtk program is presently broken due to API changes.  I have included patches at the bottom of this message.) I found that some files would display properly and some would not.  I also found that it seemed to be related to the display and graphics card.  Here are the results: ATI Radeon 9000 with dual screen using ati driver: screen 0: 1400x1050 works: 256x192, 100x100, doesn't work: 400x400, 300x300, 400x300 screen 1: 1600x1200 works: 256x192, 400x400, 100x100 doesn't work: 300x300, 400x300 NVIDIA on  1280x1024 using nvidia driver works: 100x100, 256x192, 300x300, 400x300, 400x400 doesn't work: I get the same results with cairo-1.0.4 and cairo-1.2.0. Can anyone tell me what is wrong?  Is this a cairo bug? Thanks Bob Gibbs /*********************** START SIMPLE PROGRAM ***************************/ #include <math.h> #include <cairo.h> #include <gtk/gtk.h> /*cc `pkg-config gtk+-2.0 --cflags --libs` test-png.c */ #define WINDOW_WIDTH 400 #define WINDOW_HEIGHT 400 static cairo_surface_t *surface; static void create_surface() {         surface = cairo_image_surface_create_from_png ("romedalen5.png"); } static void snippet_normalize (cairo_t *cr, double width, double height) {     cairo_scale (cr, width, height);     cairo_set_line_width (cr, 0.04); } static void do_blit(cairo_t *cr) {         int w, h;         snippet_normalize (cr, WINDOW_WIDTH, WINDOW_HEIGHT);         w = cairo_image_surface_get_width (surface);         h = cairo_image_surface_get_height (surface);         printf("w=%d, h=%d\n", w, h);         cairo_translate (cr, 0.5, 0.5);         cairo_rotate (cr, 45* M_PI/180);         cairo_scale  (cr, 1.0/w, 1.0/h);         cairo_translate (cr, -0.5*w, -0.5*h);         cairo_set_source_surface (cr, surface, 0, 0);         //cairo_pattern_set_extend(cairo_get_source(cr), CAIRO_EXTEND_REPEAT);         cairo_paint (cr); } static void paint(GtkWidget *w, GdkEvent *event) {         cairo_t *c;         c = gdk_cairo_create(w->window);         do_blit(c);         cairo_destroy(c); } int main(int argc, char **argv) {         GtkWidget *w, *da;         create_surface();         gtk_init(&argc, &argv);         w = gtk_window_new(GTK_WINDOW_TOPLEVEL);         da = gtk_drawing_area_new();         gtk_widget_set_size_request(w, WINDOW_WIDTH, WINDOW_HEIGHT);         g_signal_connect(da, "expose-event", G_CALLBACK(paint), NULL);         gtk_container_add(GTK_CONTAINER(w), da);         gtk_widget_show_all(w);         gtk_main();         return 0; } /*********************** END SIMPLE PROGRAM ***************************/ PATCHES: Index: cairo_snippets_gtk.c =================================================================== RCS file: /cvs/cairo/cairo-demo/cairo_snippets/cairo_snippets_gtk.c,v retrieving revision 1.4 diff -a -u -r1.4 cairo_snippets_gtk.c --- cairo_snippets_gtk.c        11 Jan 2005 22:38:03 -0000      1.4 +++ cairo_snippets_gtk.c        11 Aug 2006 01:06:37 -0000 @@ -3,7 +3,6 @@   */  #include "snippets.h" -#include <gtkcairo.h>  #include <gtk/gtk.h>  #include <stdio.h> @@ -13,15 +12,19 @@  static void  paint (GtkWidget *widget, -        cairo_t   *cr, -        void      *data) +        GdkEvent *event)  { +    cairo_t *cr; + +    cr = gdk_cairo_create(widget->window); +      gint width = widget->allocation.width ;      gint height = widget->allocation.height;      cairo_save (cr);        snippet_do (cr, current_snippet, width, height);      cairo_restore (cr); +    cairo_destroy(cr);  }  static void @@ -123,10 +126,10 @@      hpaned = gtk_hpaned_new ();      vpaned = gtk_vpaned_new (); -    gtkcairo = gtk_cairo_new (); +    gtkcairo = gtk_drawing_area_new ();      gtk_widget_set_usize (GTK_WIDGET (gtkcairo), 256, 256); -    g_signal_connect (G_OBJECT (gtkcairo), "paint", +    g_signal_connect (G_OBJECT (gtkcairo), "expose-event",                        G_CALLBACK (paint), NULL);      source_view = create_source_view (); Index: <a href="http://configure.ac" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">configure.ac</a> =================================================================== RCS file: /cvs/cairo/cairo-demo/cairo_snippets/configure.ac,v retrieving revision 1.3 diff -a -u -r1.3 <a href="http://configure.ac" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">configure.ac</a> --- <a href="http://configure.ac" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)"> configure.ac</a>        24 Feb 2005 16:21:01 -0000      1.3 +++ <a href="http://configure.ac" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">configure.ac</a>        11 Aug 2006 01:06:37 -0000 @@ -9,7 +9,7 @@  AC_STDC_HEADERS  PKG_CHECK_MODULES(SNIPPETS, libpng libsvg-cairo >= 0.1.2 cairo >= 0.3.0) -PKG_CHECK_MODULES(GTKCAIRO, gtkcairo, enable_gtkcairo=yes, enable_gtkcairo=no) +PKG_CHECK_MODULES(GTKCAIRO, gtk+- 2.0 >= 2.8, enable_gtkcairo=yes, enable_gtkcairo=no)  AM_CONDITIONAL(BUILD_GTKCAIRO, test x$enable_gtkcairo = xyes)